Glossary extracted starting with automatic seeds, with BOW for the domain met and language EN

aerated lagoon	a holding and/or treatment pond that speeds up the natural process of biological decomposition of organic waste by stimulating the growth and activity of bacteria that degrade organic waste.
system element	System elements are the kinds of things or substances composing the system
debris avalanche	a downward slide of loose, earthen material (soil, mud, and small rocks) that begins suddenly and travels at great speeds — similar to a snow avalanche
volcano	Its any place where lave, ash or volcanic gases escape to the surface
hydrostatic head	In hydrologic terms, a measure of pressure at a given point in a liquid in terms of the vertical height of a column of the same liquid which would produce the same pressure
frequency curve	A curve that expresses the relation between the frequency distribution plot, with the magnitude of the variables as abscissas and the number of occurrences of each magnitude in a given period as ordinates
aphelion	The point on the earth's orbit that is farthest from the sun
ice crystals	A barely visible crystalline form of ice that has the shape of needles, columns or plates
isobar	A line connecting points of equal pressure.
second-day feet	The volume of water represented by a flow of one cubic foot per second for 24 hours; equal to 84,000 cubic feet
haystack	A large standing wave caused by deceleration of current.
earthlight	The faint illumination of the dark part of the moon's disk produced by sunlight reflected onto the moon from the earth's surface and atmosphere.
trace	Generally, an unmeasurable or insignificant quantity
composite hydrograph	A stream discharge hydrograph which includes base flow, or one which corresponds to a net rain storm of duration longer than one unit period.
reverse osmosis	a water treatment method whereby water is forced through a semipermeable membrane which filters out impurities.
gradient	Gradient (GRAD)
volcano	An elevated area of land created from the release of lava and ejection of ash and rock fragments from and volcanic vent.
continental air mass	A dry air mass originating over a large land area.
inselberg	A German term used to describe a steep-sided hill composed of rock that rises from a pediplain.
geology	The field of knowledge that studies the origin, structure, chemical composition, and history of the Earth and other planets.
in-situ flushing	introduction of large volumes of water, at times supplemented with cleaning compounds, into soil, waste, or groundwater to flush hazardous contaminants from a site.
earthen dam	An embankment dam in which more than 50% of the total volume is formed of compacted fine-grained material
altitude	A measure of height of an object, usually with reference to the Earth's surface, or sea level.
syria planum*	A martian plateau located at -15°, 105°, southeast of Tharsis, from a placename applied in 1958 by the IAU to a portion of Thaumasia
wrr	the World Radiometric Reference, which provides the basis for all measurements by radiometers in the world
land application	discharge of wastewater onto the ground for treatment or reuse.
aphelion	The location in the orbit when Earth (or any other planet) is farthest away from the Sun.
coefficient of determination	Statistic that measures the proportion of the variation in the dependent variable that is associated with the statistical regression of an independent variable
relief	The range of topographic elevation within a specific area.
map scale	Ratio between the distance between two points found on a map compared to the actual distance between these points in the real world.
infrared	visible, ultraviolet, x-rays, gamma rays, and cosmic rays.
origin	The arbitrary starting point on a graph or grid coordinate system
dissolution	The process of a substance dissolving and dispersing into a liquid.
cooling degree-day	A measure of the need for air conditioning when the average daily temperature is above 65 ·F (18 ·C); computed by subtracting 65 ·F from the average daily temperature in ·F.
ultramafic	Rock that is rich in magnesium and iron content.
appropriation doctrine	the system for allocating water to private individuals used in most Western states
backscattering	Portion of solar radiation directed back into space as a result of particle scattering in the atmosphere.
angle of rest	angle at which material will remain stable
face	The external surface of a structure, such as the surface of a dam.
flood plain	Any land area susceptible to being inundated by water from any source
temperature	The measure of molecular motion or the degree of heat of a substance
foot	The bottom edge of a sail.
shortwave radiation	Electromagnetic radiation with a wavelength between 0.1 and 0.7 micrometers (µm)
mean solar day	Time it takes to complete one Earth rotation relative to the position of the Sun (for example, from midnight to midnight)
effluent limitation	restrictions established by a a regulating agency such as a State or the EPA in an NPDES permit on quantities, rates, and concentrations in wastewater discharges.
gravity	The force exerted by the Earth that pulls bodies toward it.
law of basin areas	Morphometric relationship observed in the mean basin area size of stream segments of a particular classification order in stream channel branching
ice boom	A floating structure designed to retain ice.
thermosphere	Atmospheric layer above the mesosphere (above 80 kilometers) characterized by air temperatures rising rapidly with height
breakup jam	Ice jam that occurs as a result of the accumulation of broken ice pieces.
floe	An accumulation of frazil flocs (also known as a "pan") or a single piece of broken ice.
thunderstorm	they are completely detached from the base of the cumulonimbus cloud.
vaclusian stream	A stream that begins underground.
heterosphere	The upper layer in a two part classification of the atmosphere based on the general homogeneity of chemical composition
maximum	The greatest value attained by a function, for example, temperature, pressure, or wind speed
utopia planitia*	A martian plain located at 40°, 260°
dyne	A unit of force that creates an acceleration on a mass of 1 gram equal to 1 centimeter per second
hot spot	A volcanic area on the surface of the Earth created by a rising plume of magma.
impaired water body	a water body that has been determined under state and federal law as not meeting water quality standards, or having the potential to do so in the future.
striations	Grooves of scratches found in surface rock that are the result of glacial abrasion.
decomposable waste	waste that under suitable natural conditions can be transformed through biological and chemical processes into compounds that do not impair water quality.
osmosis	the passage of a liquid from a weak solution to a more concentrated solution across a semi-permeable membrane that allows passage of the solvent (water) but not the dissolved solids.
outburst flood	See Jokulhlaup.
ions	Electrically charged atoms or molecules.
scale	A specific relative or proportional size or extent of a phenomena as measured through space and/or time.
mesonet	A regional network of observing stations (usually surface stations) designed to diagnose mesoscale weather features and their associated processes.
meteorite	a chunk of rock and/or metal that has broken off a larger space object, such as an asteroid or a comet, and falls to Earth's surface.
discharger	any person who discharges waste that could affect the quality of state waters
penumbra	Outer, lighter area of a sunspot.
laterization	Soil forming process that creates a laterite layer.
reference mark	A relatively permanent point of known elevation which is tied to a benchmark.
cfs	Cubic feet per second
sewer	a system of underground pipes that collect and deliver wastewater to treatment facilities or streams.
oceanography	The study of the ocean, embracing and integrating all knowledge pertaining to the ocean's physical boundaries, the chemistry and physics of sea water, and marine biology.
sidecurler	A reversal parallel to the main current, formed by a side current passing over a rock as it enters the main channel.
migration	Movement of organisms in an intentional way between two points in space
spatial analysis	The examination of the spatial pattern of natural and human-made phenomena using numerical analysis and statistics.
dambrk	The Dam Break Forecasting Model.
stream	A long narrow channel of water that flows as a function of gravity and elevation across the Earth's surface
funnel cloud	A tornado which is beginning its descent from the base of a cumulonimbus cloud
solar panel	a source of power for satellites, made up of many individual solar cells, which are devices for transforming the energy of sunlight into electricity.
water recycling	the treatment of wastewater making it suitable for reuse.
tropical disturbance	A discrete tropical weather system of apparently organized convection -- generally 100 to 300 nmi in diameter -- originating in the tropics or subtropics, having a nonfrontal migratory character, and maintaining its identity for 24 hours or more
permanent work	Work that must be performed through repairs or replacement to restore an eligible facility on the basis of its pre-disaster design, use and current applicable standards
pulaski	a combination ax and hoe, used to dig a fireline
fissure	a crack in Earth's surface through which volcanic materials can escape.
ground water	Water within the earth that supplies wells and springs; water in the zone of saturation where all openings in rocks and soil are filled, the upper surface of which forms the water table
h-alpha	In solar-terrestrial terms, this absorption line of neutral hydrogen falls in the red part of the visible spectrum and is convenient for solar observations
head	In hydrologic terms, the difference between the pool height and tailwater height
circulate	to move in a circle, circuit or orbit; to flow without obstruction; to follow a course that returns to the starting point.
wavelength	the distance between adjacent peaks or troughs of a wave
natural selection	Environment's influence on the reproductive success of individuals in a population
periglacial	Landforms created by processes associated with intense freeze-thaw action in an area high latitude areas or near an alpine or continental glacier.
spray irrigation	application of finely divided water droplets to crops using artificial means.
mutualism	Interspecific interaction where both species experience and increase in their fitness after interacting with the other species
small circle	A circle on the globe's surface that does not bisect the center of the Earth
microorganism	Extremely small organism that can only be seen using a microscope.
greenhouse warming	The possible heating of the planet over and above the natural greenhouse effect as a result of increases in atmospheric carbon dioxide.
leachate	water containing contaminants which leaks from a disposal site such as a landfill or dump.
diurnal	daily, or the daily cycle
ring of fire	the name given to the geologically active belt around the Pacific Ocean that is home to more than 75 percent of the world's volcanoes.
steppe	Russian term for mid-latitude grasslands.
storage equation	The equation for the conservation of mass.
base	a substance that has a pH of more than 7, which is neutral
boulder fan	A sloping, fan-shaped mass of boulders deposited by a tributary stream where it enters into the main canyon
methoxychlor	pesticide that causes adverse health effects when found in domestic water supplies
solar constant	A term used to describe the average quantity of solar insolation received by a horizontal surface at the edge of the Earth's atmosphere
gradient wind	Any horizontal wind velocity tangent to the contour line of a constant-pressure surface (or to the isobar of a geopotential surface) at the point in question
acid	a substance that has a pH of less than 7, which is neutral
richter scale	A logarithmic measurement scale of earthquake magnitude
duration curve	A cumulative frequency curve that shows the percent of time during which specified units of items (e.g
forcing	A term used to describe the situation where a change or an event in one part of the atmosphere causes a strengthening change in another part of the atmosphere
instability	The tendency for air parcels to accelerate when they are displaced from their original position. The greater the instability, the greater the potential for severe thunderstorms. One way instability is measured is with a value of CAPE (Convective Available Potential Energy) in Joules per kilogram (energy per unit mass).
runway visual range	An instrumentally-derived value, based on standard calibrations, that represents the horizontal distance a pilot may see down the runway from the approach end.
spin-stabilized	Attitude control is done by having the entire satellite spin
u.s. geological survey	The Federal Agency chartered in 1879 by congress to classify public lands, and to examine the geologic structure, mineral resources, and products of the national domain
rainbow	Groups of concentric arcs with colors ranging from violet to red, produced on a "screen" of water drops (raindrops, droplets of drizzle or fog) in the atmosphere by light from the Sun or Moon
equator	The imaginary great circle of 0 degrees latitude on the Earth's surface, separating the Northern Hemisphere from the Southern Hemisphere.
species diversity	Number of different species in a given region.
relative humidity	the ratio of the current amount of vapor in the air to how much vapor the air can hold at saturation
highest astronomical tide	The highest level of water that can be predicted to occur under average meteorological conditions and any combination of astronomical conditions
fundamental niche	Describes the total range of environmental conditions that are suitable for a species existence without the effects of interspecific competition and predation from other species.
ngvd	National Geodetic Vertical Datum
observation météorologique en surface	Une observation météorologique en surface est une évaluation d'éléments météorologiques, faite visuellement et/ou à l'aide d'instruments, à un endroit précis de la surface de la Terre, généralement une station d'observation météorologique.
rcbap	Residential Condominium Building Association Policy
nutrient cycle	the cyclic conversions of nutrients from one form to another within biological communities
strata	The layers or beds found in sedimentary rock.
gelisols	Soil order (type) of the United States Natural Resources Conservation Service Soil Classification System
hic	The Hydrometeorological Information Center of the Office of Hydrology (OH).
lightning	A visible electrical discharge produced by thunderstorms caused by an imbalance of electrons between different storm cells or between the thunderstorm and the ground.
geomorphology	The field of knowledge that investigates the origin of landforms on the Earth and other planets.
conservation tillage	the practice of leaving vegetation on fields during idle periods to protect the soil from erosion and trap moisture.
shield volcano	a volcano with long, gentle slopes, built primarily by lava flows.
geostationary orbit	Satellite that has an orbit that keeps it over the same point on the Earth at all times
non-clastic sedimentary rock	Sedimentary rocks that are created either from chemical precipitation and crystallization, or by the lithification once living organic matter.
bedding plane	A layer in a series of sedimentary beds that marks a change in the type of deposits.
hydrocarbons	chemical compounds that consist entirely of carbon and hydrogen; also referred to as volatile organic compound.
mantle	fiercely hot rock 1,800 miles deep beneath the crust
boat	Raft
endangered species	one having so few individual survivors that the species could soon become extinct in all or part of its region.
scoria	bubble-filled stones ejected from a volcano
thalweg	the line of maximum depth in a stream
ph	a measure of the relative acidity or alkalinity of water
double-oar turn	Rowing technique used to turn (or to prevent the turning of) a raft
laboratory water	purified water used in the laboratory as a basis for making up solutions or making dilutions
measurement uncertainty	the bounds that should be placed on a measured value because of uncertainties in the measurement
lobe	A tongue-like extension of some material
rate of change	The derivative or change in a parameters value with respect to time
salinity	amount of dissolved salts in a given volume of water.
atmosphere	A gaseous covering to a planet that is bound by gravity
community water system	In Texas, a public water system which has a potential to serve at least 15 residential service connections on a year-round basis or serves at least 25 residents on a year-round basis.
point discharge	Instantaneous rate of discharge, in contrast to the mean rate for an interval of time.
temp	Temperature- A measure of the internal energy that a substance contains
average	The result you get when you add several amounts together and divide the total by the number of amounts.
bowen reaction series	Model that explains the origin of the various types of igneous rocks
present movement	The best estimate of the movement of the center of a tropical cyclone at a given time and given position
langley	Unit of the intensity of radiation measured per minute and equal to one calorie.
pore pressure	The interstitial pressure of water within a mass of soil, rock, or concrete.
explosive eruption	Volcanic eruption where high-viscosity granite-rich magma causes an explosion of ash and pyroclastic material
hummocked ice	Ice piled haphazardly one piece over another to form an uneven surface.
painter	A line, usually about 20 feet long, attached to the bow of paddle rafts and the stern of oar rafts
hipaa	Health Insurance Portability and Accountability Act of 1996
magnetic reversal	A change in the polarity of the Earth's magnetic field
matric force	Force that holds soil water from 0.0002 to 0.06 millimeters from the surface of soil particles
accuracy	The degree of conformity of an indicated value to an accepted standard value, or ideal value
dormant	when a volcano remains inactive for a long time
circumsolar radiation	the amount of solar radiation coming from a circle in the sky centered on the sun's disk and having a radius of between 2.5 and 3.5 degrees, depending on the type of instrument being used to measure beam radiation (direct normal irradiance)
desalinate	To remove salt from.
initial loss	In hydrology, rainfall preceding the beginning of surface runoff
biomass	The weight of living tissues usually measured per unit area over a particular time interval
variance	The sum of the squared deviations divided by one less than the number of elements in the set.
map	The average rainfall over a given area, generally expressed as an average depth over the area.
force of acceleration	Force resulting in the speed of a moving body to increase.
mass curve	A graph of the cumulative values of a hydrologic quantity (such as precipitation or runoff), generally as ordinate, plotted against time or date.
graphic scale	Way of expressing the scale of a map with a graphic.
indicator organisms	microorganisms, such as coliforms, whose presence is indicative of pollution or of more harmful microorganism.
cartwheeling	Technique of spinning a raft just before a collision with a rock so as to rotate the raft off and around the rock.
seal	the impermeable material, such as cement grout bentonite, or puddling clay placed in the annular space between the borehole wall and the casing of a water well to prevent the downhole movement of surface water or the vertical mixing of artestian waters.
sneak	To take an easy route around a difficult spot
perchloroethylene	a chlorinated solvent commonly used in dry cleaning
flooding	A general and temporary condition of partial or complete inundation of normally dry land areas from the overflow of inland or tidal water, or rapid accumulation or runoff of surface waters from any source
fold mountains	Compressed sedimentary rocks that rise in a series of concertina-like folds.
minimum streamflow	the specific amount of water reserved to support aquatic life, to minimize pollution, or for recreation
op	FEMA’s Office of Policy and Regional Operations
nom de la station	Le nom de la station est le nom officiel de chaque station météorologique attribué par le Service météorologique du Canada (SMC), tel qu'inscrit dans les Archives climatiques nationales.
dyke	Thin vertical veins of igneous rock that form when magma enters and cools in fractures found within the crust
spotting	the starting of new fires, called spot fires, by sparks and embers that drift ahead of an advancing wildfire.
liquid	A state of matter where molecules have the ability to flow and the surface of this mass displays the property of surface tension.
cone	the sloping walls of a volcano (not all volcanoes have cones).
port	Nautical term for the left side of a yacht when facing forward.
system boundary	Outer edge of system
distribution graph	A unit hydrograph of direct runoff modified to show the proportions of the volume of runoff that occur during successive equal units of time.
sinkhole	A pit like hole in found in areas of karst
correlation coefficient	Statistic that measures the degree of linear association between two variables
discharge	The rate at which water passes a given point
capillary potential	The work required to move a unit mass of water from the reference plane to any point in the soil column.
parameter	An independent variable.
salinity	Concentration of dissolved salts found in a sample of water
high frequency	The portion of the radio frequency spectrum between between 3 and 30 MHz
immigrant species	Species that migrate into an ecosystem or that are deliberately or accidentally introduced into an ecosystem by humans
radiant energy	Energy in the form of electromagnetic waves and photons
speciation	The process by which new species originate through mutations, natural selection, and evolution.
halo	The ring of light that seems to encircle the sun or moon when veiled by cirrus clouds
trash rack	A screen located at an intake to prevent debris from entering.
remote sensing	the determination of a quantity by detecting it from a distance
dust dome	Dome of air that surrounds a city created from the urban heat island effect that traps pollutants like particulate matter.
wind power	power, usually in the form of electricity, derived from the wind.
validation	comparison of computer model results with a set of data that were not used for calibration.
traction	Erosional movement of particles by rolling, sliding and shuffling along the eroded surface
ground-water recharge	inflow of water to a ground-water reservoir from the surface
plateau	High altitude area of land, unbroken by mountain ranges.
hardness	a water-quality indication of the concentration of alkaline salts in water, mainly calcium and magnesium
withdrawal	water removed from a ground- or surface-water source for use.
crust	the outermost layer of Earth, varying in thickness from 3.5 miles (5 kilometers) to 50 miles (80 kilometers).
flocculation	Chemical processes where salt causes the aggregation of minute clay particles into larger masses that are too heavy to remain suspended water.
hail	Balls or chunks of ice larger than 1/4 inch in diameter which are produced due to strong updrafts in thunderstorms.
medium range	In forecasting, (generally) three to seven days in advance.
hurricane local statement	A public release prepared by local National Weather Service offices in or near a threatened area giving specific details for its county/parish warning area on (1) weather conditions, (2) evacuation decisions made by local officials, and (3) other precautions necessary to protect life and property.
remote sensing	The gathering of information from an object or surface without direct contact.
livestock water use	water used for livestock watering, feed lots, dairy operations, fish farming, and other on-farm needs.
stopper	A reversal powerful enough to stop a raft momentarily
westerlies	Usually applied to the broad patterns of persistent winds with a westerly component
mitochondria	Organelle in a cell that oxidizes organic (see respiration) energy for use in cellular metabolism.
place	A term used in geography that describes the factors that make the location of natural and human-made phenomena unique.
mist	A collection of microscopic water droplets suspended in the atmosphere
coastal zone	Relatively nutrient-rich, shallow part of the ocean that extends from the high-tide mark on land to the edge of the continental shelf.
sels	Synoptic Scale (or Large Scale) - Size scale referring generally to weather systems with horizontal dimensions of several hundred miles or more
high energy event	In solar-terrestrial terms, flares (class two or more) with outstanding Centimetric Bursts and SID
endangered species	A species found in nature that has so few surviving individuals that the it could soon become extinct in all or most of its natural range
overturned fold	A fold in rock layers where one limb is pushed past the perpendicular
south magnetic pole	Location in the Southern Hemisphere where the lines of force from Earth's magnetic field are vertical
chemical weathering	Breakdown of rock and minerals into small sized particles through chemical decomposition.
resource partitioning	The evolutionary process of species living in the same ecosystem dividing up resources so that each species develops dissimilar resource requirements to avoid competition
natural control	A stream gaging control which is natural to the stream channel, in contrast to an artificial control structure by man.
intermediate zone	The subsurface water zone below the root zone and above the capillary fringe.
sand	Mineral particle with a size between 0.06 and 2.0 millimeters in diameter
return flow	South winds on the back (west) side of an eastward-moving surface high pressure system
outfall	the place where a sewer, drain, or stream discharges; the outlet or structure through which reclaimed water or treated effluent is finally discharged to a receiving water body.
kilowatthour	a power demand of 1,000 watts for one hour
trihalomethanes	chemical compounds in which three of the four hydrogen atoms of methane (CH4) are replaced by halogen atoms
gradient wind	A theoretical horizontal wind that blows parallel to curved isobars or contours above the friction layer.
hydrologic unit	is a geographic area representing part or all of a surface drainage basin or distinct hydrologic feature.
perihelion	It is the point in the Earth's orbit when it is closest to the Sun (147.5 million km)
soft water	any water that does not contain a significant amount of dissolved minerals such as salts of calcium or magnesium.
recumbent fold	A fold in which the axial plane is almost horizontal.
noi	Notice of Interest
kingdom	Top most level of the common system used to classify life
flood frequency curve	(1) A graph showing the number of times per year on the average, plotted as abscissa, that floods of magnitude, indicated by the ordinate, are equaled or exceeded
heure normale locale	C'est l'heure normale locale qui est utilisée aux fins des observations; c'est l'heure normale du fuseau horaire où est située la station, que l'heure « avancée » ait ou non été adoptée pour d'autres fins
molecules	Composed of atoms, molecules are the smallest units of a substance that retain the chemical properties of that substance.
extinction	complete disappearance of a species because of failure to adapt to environmental change.
podzolization	Soil forming process that produces a strongly leached soil with a distinctive iron hardpan layer in the B horizon
collada	A strong, steady wind blowing from the north or northwest in the upper part of the Gulf of California and from the northeast in the lower part.
one-tailed statistical test	Is an inferential statistical test where the values for which one can reject the null hypothesis are located entirely in one side of the center of the probability distribution.
hail	A mixture of liquid and frozen precipitation
comet	A large mass of ice and dust that has an orbit around a star.
flood control storage	Storage of water in reservoirs to abate flood damage.
conduction	The transfer of heat through a substance by molecular action or from one substance by being in contact with another.
furrow irrigation	irrigation method in which water travels through the field by means of small channels between each group of rows.
white eddy	A reversal below a ledge or other underwater obstruction characterized by a foamy backflow at the surface.
sun glint	An example of reflection of sunlight by gently rippled water.
isobar	A line connecting equal points of pressure.
standing rigging	The non-moving rods and lines that support the mast and sails.
iea	the International Energy Agency, an autonomous agency linked to the Organisation for Economic Co-operation and Development.
beam	A boat's greatest width.
barotropic systems	on the other hand, do not exhibit significant changes in intensity
dust electrification	The transfer of charges that occur when dust particles collide with each other, sand particles or the surface.
hydrograph separation	The process where the storm hydrograph is separated into baseflow components and surface runoff components.
substation	A location where observations are taken or other services are furnished by people not located at NWS offices who do not need to be certified to take observations.
beta particle	Electron emitted from the nucleus of a radioactive isotope
freezeup date	Date on which the water body was first observed to be completely frozen over.
mesocyclone	Like the mesocyclone, specific criteria involving strength, vertical depth, and time continuity must be met in order for a signature to become a TVS
tower	(Short for towering cumulus), a cloud element showing appreciable upward vertical development.
outlet	An opening through which water can be freely discharged from a reservoir.
estimator	An estimator is any value calculated from the sample data For example, the sample mean is an estimator of the population mean.
trophic level	Level of organization in the grazing food chain.
updraft base	Alternate term for a rain-free base.
frost	White ice crystals that form on a surface, like the ground or leaves of a plant
limiting factor	Abiotic condition that most controls the growth of a species
triple-rig	Same as Threesome Raft.
capillary action	the means by which liquid moves through the porous spaces in a solid, such as soil, plant roots, and the capillary blood vessels in our bodies due to the forces of adhesion, cohesion, and surface tension
incident angle	the angle that a ray (of solar energy, for example) makes with a line perpendicular to the surface
thermal infrared radiation	Form of electromagnetic radiation with a wavelength between 3 to 14 micrometers (µm).
coe	U.S
fluid drag	Reduction in the flow velocity of a fluid by the frictional effects of a surface.
conversion	A change in form or units.
distance ratio	Method for measuring the gradient of a slope
air mass	A large body of air, up to several hundred miles wide and several miles deep, that moves across the earth.
thermodynamics	Study of the processes that involve the transformation of heat into mechanical work, of mechanical work into heat, or the flow of heat from a hotter body to a colder body.
epa	Environmental Protection Agency. The federal regulatory agency responsible for protecting environmental quality throughout the nation
hurricane local statement	A public release prepared by local National Weather Service Field Offices in or near a threatened area, giving specific details for its county/parish warning area on: 1) weather conditions; 2) evacuation decisions made by local officials; and 3) other precautions necessary to protect life and property.
ph	Scale used to measure the alkalinity or acidity of a substance through the determination of the concentration of hydrogen ions in solution
undercurrent	A current below the upper currents or surface of a fluid body.
glacier	a huge mass of ice, formed on land by the compaction and recrystallization of snow, that moves very slowly downslope or outward due to its own weight.
indicator species	Species that can be used as a early indicator of environmental degradation to a community or an ecosystem
hydroelectric plant	electric power plant in which the energy of falling water is used to spin a turbine generator to produce electricity.
albedometer	An instrument used for the measurement of the reflecting power (the albedo) of a surface
wave period	This is the time taken between when any part of a wave passes a fixed point and when the same part of the next wave passes that point.
federal register	The document, published daily by the Federal Government, which presents regulation changes and legal notices issued by Federal agencies
thalweg	The line of maximum depth in a stream
datacol	The Software System that supports RFC gateway functions.
lichen	Organism that consists of a symbiotic joining of a species of fungi and a species of algae.
mica	Silicate mineral that exhibits a platy crystal structure and perfect cleavage
drizzle	Small, slowly falling water droplets, with diameters between .2 and .5 millimeters.
roller wave	A reversal
floodway / regulatory floodway	The channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base (1%-annual-chance) flood without cumulatively increasing the water surface elevation more than a designated height.
plucking	Erosive process of particle detachment by moving glacial ice
emergency public shelter	Generally a public school or other such structure designated by county officials as a place of refuge.
independent variable	Variable in a statistical test that is thought to be controlling through cause and effect the value of observations in another dependent variable modeled in the test.
deciduous vegetation	Type of vegetation that sheds its leaves during winter or dry seasons
jet max	Severe weather potential sometimes increases in this area as a result
recurrence interval	The average time period that separates natural events of a specific magnitude
cation	An ion carrying a positive atomic charge.
pioneer community	Community dominated by pioneer species of plants.
ceiling	The height of the lowest layer of broken or overcast cloud layer.
metamorphic rock	A rock that forms from the recrystallization of igneous, sedimentary or other metamorphic rocks through pressure increase, temperature rise, or chemical alteration.
treatment	any method, technique, or process designed to remove solids and/or pollutants from solid waste, waste-streams, and effluents.
australian height datum	The datum (adopted by the National Mapping Council of Australia) to which all vertical control for mapping is to be referred to.
staff gage	A vertical staff graduated in appropriate units which is placed so that a portion of the gage is in the water at all times
visibility	The horizontal distance an observer can see and identify a prominent object.
salinity	A measure of the quantity of dissolved salts in sea water
hail index	An indication of whether the thunderstorm structure of each storm identified is conducive to the production of hail.
nuclear energy	Energy released when the nucleus of an atom experiences a nuclear reaction like the spontaneous emission of radioactivity, nuclear fission, or nuclear fusion.
floodproofing	Any combination of structural and nonstructural additions, changes, or adjustments to structures which reduce or eliminate flood damage to real estate or improved real property, water and sanitary facilities, structures and their contents.
mesocyclone	specific criteria involving strength, vertical depth, and time continuity must be met in order for a signature to become a TVS
desertification	the process by which semiarid lands turn to desert (also called land degradation)
live capacity	The total amount of storage capacity available in a reservoir for all purposes, from the dead storage level to the normal water or normal pool level surface level
mcs	and can produce damaging straight-line winds over areas hundreds of miles long and more than 100 miles across.
debris basin	a concrete, bowl-shaped pit built on a mountainside to catch debris from mud and rock slides
physical weathering	breaking down of parent rock into bits and pieces by exposure to temperature and changes and the physical action of moving ice and water, growing roots, and human activities such as farming and construction
formula	A scientific or mathematical rule expressed in symbols.
spectrum	Is a graph that describes the quantity of radiation that is emitted from a body at particular wavelengths.
overflow rate	one of the guidelines for design of the settling tanks and clarifiers in a treatment plant.
marble	Metamorphic rock created by the recrystallization of calcite and/or dolomite.
algorithm	A computer program (or set of programs) which is designed to systematically solve a certain kind of problem
gleysol soil	Soil order (type) of the Canadian System of Soil Classification
keeper	A reversal capable of trapping araft for long periods
hydrocarbon	Organic compound composed primarily of hydrogen and carbon atoms
fault-block mountains	Mountains formed by the vertical movement of rocks along a set of fault lines.
diffraction	The result of light waves interfering with other after passing through a narrow aperture, causing them to bend or spread.
chromosphere	Portion of the sun above the photosphere; consists of transparent ionized hydrogen and helium at 4000 to 40,000 ·C.
stage marker	A gauge placed along a river shoreline that is calibrated in feet orfractions thereof starting from an arbitrary zero point
succession	Directional cumulative change in the types plant species that occupy a given area, through time.
anti cyclonic rotation	Rotation in the opposite sense as the Earth's rotation, i.e., clockwise in the Northern Hemisphere as would be seen from above
tropic of capricorn	A solstice position of the sun with a latitude of 23 degrees, 30 minutes S.
inosilicate	Subclass of the silicate class of minerals
mutation	Change in the structure of a gene or chromosome.
oar clip	A piece of resilient metal in the shape of a pinched U that is used to hold an oar to the thole pin.
pyroxene	A group of single chained inosilicate minerals whose basic chemical unit is the silica tetrahedron (SiO4)
solid-state imaging instrument	A camera currently in use on the space exploration satellite Galileo.
dynamics	Generally, any forces that produce motion or affect change
second law of thermodynamics	This law states that heat can never pass spontaneously from a colder to a hotter body
celestial sphere	The apparent sphere of infinite radius having the earth as its center
fault plane	The plane that represents the fracture surface of a fault.
piping	The progressive development of internal erosion by seepage, appearing downstream as a hole or seam discharging water that contains soil particles.
halite	Sedimentary rock created by the chemical precipitation of sodium and chlorine.
cnif	Calibration Network Information Files
easting	First measurement of a grid reference used to specific the location of a point on a rectangular coordinate system
tropical depression	An early stage in the development of a hurricane; sustained winds are at least 37 km (23 mi) per hour but less than 63 km (39 mi) per hour.
irrigation water use	water application on lands to assist in the growing of crops and pastures or to maintain vegetative growth in recreational lands, such as parks and golf courses.
eustacy	Variations in sea-level that are related to changes in the volume of seawater in the oceans.
specialist species	Species that have a relatively narrow ecological niche
mixed tide	Tides that have a higher high water and lower high water as well as higher low water and lower low water per tidal period.
tectonic plate	An extensive layer of lithosphere that moves as a discrete unit on the surface of the Earth's asthenosphere.
frozen precipitation	Precipitation that reaches the ground in a frozen state
ozone	Tri-atomic oxygen that exists in the Earth's atmosphere as a gas
ecological niche	Is all of the physical, chemical and biological conditions required by a species for survival, growth and reproduction
indirect flood damage	Expenditures made as a result of the flood (other than repair) such as relief and rescue work, removing silt and debris, etc.
moss	About 9,500 species of plants that belong to the division bryophyta
area-capacity curve	A graph showing the relation between the surface area of the water in a reservoir, the corresponding volume, and elevation.
creeping	the slow, gradual movement of a hill's upper layers caused by the pull of gravity on loose stones, gravel, and soft topsoil
heat capacity	Is the ratio of the amount of heat energy absorbed by a substance compared to its corresponding temperature rise.
grip	The extreme upper end of a single-bladed paddle, shaped for holding with the palm over the top.
solubility	the amount of mass of a compound that will dissolve in a unit volume of solution.
myriad	A large, unspecified number.
remote sensor	Mechanical devices used to remotely sense an object or phenomenon.
response time	The amount of time in which it will take a watershed to react to a given rainfall event.
main stem	The reach of a river/stream formed by the tributaries that flow into it.
relocated	A term used in an advisory to indicate that a vector drawn from the preceding advisory position to the latest know position is not necessarily a reasonable representation of the cyclone’s movement
stay	A rod or wire that supports the mast in a fore/aft position.
tc id	The TC ID is the identifier assigned by Transport Canada to identify meteorological reports from airport observing sites transmitted in real time in aviation formats.
alkalinity	the capacity of water for neutralizing an acid solution.
hod	The Hydrologist on Duty at an RFC.
leaching	extraction or flushing out of dissolved or suspended materials from the soil, solid waste, or another medium by water or other liquids as they percolate down through the medium to groundwater.
geologist	a scientist who studies the origin, history, and structure of Earth.
algorithm	the set of simple instructions that combine to accomplish a task
deformed ice	A general term for ice which has been squeezed together and forced upwards and downwards in places
backwashing	reversing the flow of water through a home treatment device filter or membrane to clean and remove deposits.
gypsum	Sedimentary rock created by the chemical precipitation of calcium, sulfur, and oxygen.
triple point	The point at which any three atmospheric boundaries meet
photodissociation	The process by which radiation breaks down molecules into their smallest components.
heat advection	The transfer of energy through the horizontal movements of the air.
isotherm	A line connecting locations with the same temperature.
reptile	Group of terrestrial vertebrate animals that includes turtles, tortoises, snakes, lizards, crocodiles, and alligators.
wire weight gage	A river gage comprised of a weight which is lowered to the water level
equilibrium	Equilibrium describes the average condition of a system, as measured through one of its elements or attributes, over a specific period of time.
meteor	A body of matter that enters the Earth's atmosphere from space
momentum	The product of mass and velocity.
snow density	The mass of snow per unit volume which is equal to the water content of the snow divided by its depth.
central receiver system	a solar power generator which uses a series of tracking mirrors ( heliostats) or a paraboloid (3-dimensional parabola, or dish) of mirrors to focus solar energy onto a single central receiver such as a boiler, engine, or photovoltaic array.
veld	South African grasslands.
aircraft turbulence	Irregular motion of an aircraft in flight, especially when characterized by rapid up-and-down motion, caused by a rapid variation of atmospheric wind velocities
population parameter	A value used to represent a certain quantifiable characteristic of a population
chelate	Organic substances that cause the chemical process of chelation.
nccf	NOAA Central Computer Facility
fair	This is a subjective description
symbiotic mutualism	Mutualistic interaction where the species interact physically and their relationship is biologically essential for survival.
secondary treatment	second step in most waste treatment systems, in which bacteria break down the organic parts of sewage wastes; usually accomplished by bringing the sewage and bacteria together in trickling filters or in the activated sludge process
scs	The Soil Conservation Service, now known as the NRCS (National Resources Conservation Services).
canopy	the overhanging cover formed by branches and foliage.
hydrometeorological technicians	Individuals whose duties include data collection, quality control, gage network maintenance, as well as the gathering and disseminating of data and products at NWS Forecast Offices.
herb	A nonwoody angiosperm whose above ground vegetation dies off seasonally.
residual chlorine	the available chlorine which remains in solution after the demand has been satisfied
overthrust fault	Fault produced by the fracturing of rock in a fold because of intense compression.
landslide	the movement of large amounts of soil, rocks, mud, and other debris downward and outward along a slope.
aspiration meteorograph	An instrument, for the recording of two or more meteorological parameters, in which the ventilation is provided by a suction fan.
four-man raft	A boat 4 1/2 by 9 feet that will, on small rivers, accommodate one or two people
datanet	Hydrologic Data Network Analysis Software
altocumulus	Grey to white clouds that form in groups or globular masses and look like rolls in layers or patches
normal distribution	A common probability distribution displayed by population data
boundary conditions	definition or statement of conditions or phenomena at the boundaries of a model; water levels, flows, and concentrations that are specified at the boundaries of the area being modeled.
gage height	the height of the water surface above the gage datum (zero point)
litterfall	Movement of leaves, twigs and other forms of organic matter from the biosphere to the litter layer found in soil.
agglomerate	An ice cover of floe formed by the freezing together of various forms of ice.
limestone	Sedimentary rock composed of carbonate minerals, especially calcium carbonate
liquid	A substance that can easily flow, but cannot be squeezed together easily.
parts per billion	the number of "parts" by weight of a substance per billion parts of water
stern	Rear of a boat.
firestorm	also called a blowup, it is the most explosive and violent type of wildfire.
hydrologic model	In hydrologic terms, a conceptual or physically-based procedure for numerically simulating a process or processes which occur in a watershed.
mantle	thick, dense layer of rock that lies beneath Earth's crust
index of refraction	A measure of how optically dense a substance is
nautical mile	A unit of length used in marine navigation equal to a minute of arc of a great circle on a sphere
neutralism	Interspecific interaction where the species do not directly influence each other fitness.
utility	Something useful or providing use.
tropical storm	An organized group of thunderstorms often found over a tropical ocean that generates a cyclonic flow of between 64 and 118 kilometers per hour
inversion	An increase in air temperature with height.
pc-tare	Personal Computer-Time and Attendance Report
global warming	the theory that average temperatures will rise throughout the world
latitude	The location north or south in reference to the equator, which is designated at zero (0) degrees
maximum contaminant level	the designation given by the U.S
correlation	A relationship between two values.
silcretes	Sedimentary rock created by the chemical precipitation of silica.
shale	Fine grained sedimentary rock composed of lithified clay particles.
sun-synchronous orbit	A special case of the polar orbit
corona discharge	The electrical breakdown of the isolating properties of a gas that generally causes the emission of light and a hissing sound.
fcexec	A component of the NWSRFS FCST Program.
glacial milk	Term used to describe glacial meltwater which has a light colored or cloudy appearance because of clay-sized sediment held in suspension.
correlative rights	rights that are coequal or that relate to one another, so that any one owner cannot take more than his share.
hypothesis testing	Process where an alternative and a null hypothesis are statistically tested for the purpose of falsifying a hypothesis.
genus	A group in the classification of organisms
suspended sediment	very fine soil particles that remain in suspension in water for a considerable period of time without contact with the bottom
realized niche	Describes the part of the fundamental niche that a species actually occupies.
total gross reservoir capacity	The total amount of storage capacity available in a reservoir for all purposes from the streambed to the normal water or normal water or normal pool surface level
fixed energy	A process, like photosynthesis, where organisms repackage inorganic energy into organic energy.
earthquake	a sudden shifting of masses of rock beneath Earth's surface, which releases enormous amounts of energy and sends out shock waves that cause the ground to shake.
cirrus	High-level clouds (16,000 feet or more), composed of ice crystals and appearing in the form of white, delicate filaments or white or mostly-white patches or narrow bands
diatomaceous	consisting of or abounding in diatoms, a class of unicellular or colonial algae having a silicified cell wall that persists as a skeleton after death.
guild	a group of species or organisms that use the same environmental resources (habitat, food source, etc.) or life history strategy (such as reproduction) in the same way.
unconformity	A break in the sequence of sedimentary strata
plate tectonics	the geologic theory that Earth's crust is composed of rigid plates that "float" toward or away from each other, either directly or indirectly, creating the major geologic features on the planet's surface.
sugar	Type of carbohydrate chemically based on carbon, oxygen, and hydrogen.
ionizing radiation	The emission of alpha or beta particles or gamma rays from radioisotopes
doe	in this context, always refers to the United States Department of Energy, although other departments may have the same acronym.
backwater curve	The longitudinal profile of the surface of a liquid in a non-uniform flow in an open channel, when the water surface is not parallel to the invert owing to the depth of water having been increased by the interposition of an obstruction such as a dam or weir
frostbite	The partial freezing of exposed parts of the body, causing injury to the skin and sometimes to deeper tissues.
adhesion	the molecular attraction asserted between the surfaces of bodies in contact
hardpan	Impervious layer found within the soil
fire whirl	During a natural or prescribed fire, the flames drastically heat the surface which allows for hot air near the surface to rise
catchment area	An area of land that feeds a river.
extinct volcano	a volcano that is never expected to erupt again.
state of emergency	A declaration made by the Chief Elected Official of a state, county or city government which entails a heightened level of activation and mobilization of staff to protect property and lives
lake-effect snow advisory	Heavy lake-effect snowfall amounts of generally 4 inches (10 cm) in 12 hours or less or 6 inches (15 cm) in 24 hours or less are imminent or highly likely
heavy snow warning	Issued by the National Weather Service when snowfall of 6 inches (15 cm) or more in 12 hours or 8 inches (20 cm) or more in 24 hours is imminent or occurring
flocculation	large scale treatment process involving gentle stirring whereby small particles in flocs are collected into larger particles so their weight causes them to settle to the bottom of the treatment tank.
benchmark	A permanent point whose known elevation is tied to a national network
finite difference	a method of solving the governing equations of a numerical model by dividing the spatial domain into a mesh of nodes
slip-face	The lee side of a dune where material accumulates and slides or rolls downslope.
epoch	Geologic time unit that is shorter than a period.
tropical depression	A tropical storm with maximum sustained winds near the surface of less than 39 miles (63 kilometers) an hour
snow core	A sample of either freshly fallen snow, or the combined old and new snow on the ground
conservation biology	Multidisciplinary science that deals with the conservation of genes, species, communities, and ecosystems that make up Earth's biodiversity
friction	that the flow is straight with no curvature and there is no divergence or convergence with no vertical acceleration.
zulu time	One of several names for the twenty-four hour time that is used throughout the scientific and military communities
equator	The geographic circle at 0 degrees latitude on the earth's surface
troposphere	Layer in the atmosphere found from the surface to a height of between 8 to 16 kilometers of altitude (average height 11 kilometers)
eddy viscosity	a model parameter that reproduces the effects of turbulent mixing in fluid flow.
hmd	(Hemispheric Map Discussion)- This discussion is issued once a day around 1 PM EST (2 PM EDT) and is primarily intended to provide insight into the hemispheric circulation patterns over the next 5 days
sco	State Coordinating Officer
universe	All of the observable phenomena in the celestial cosmos.
basin	An area having a common outlet for its surface runoff.
sandstone	A type of sedimentary rock that contains a large quantity of weathered quartz grains.
tropical disturbance	A discrete tropical weather system of apparently organized convection--generally 100 to 300 mi in diameter--originating in the tropics or subtropics, having a nonfrontal migratory character and maintaining its identity for 24 hours or more
temperature	Temperature is a measure of the warmth or coldness of an object or substance with reference to a standard value
sustainability	the long-term capacity of an ecosystem to maintain ecological processes and functions, biological diversity, and productivity.
vapor pressure	The pressure exerted by water molecules in a given volume of the atmosphere
storage	(1) Water artificially impounded in surface or underground reservoirs for future use
limb	The edge of a planet from the observer’s vantage point
global warming	Increased warming of the atmosphere due to increases in the amount of greenhouse gases such as carbon dioxide.
lag	The measure of the time between the center of mass of precipitation to the center of mass of runoff (on the hydrograph); basin lag is a function of not only basin characteristics, but also of storm intensity and movement
biomass	The total amount of living material in a given system.
convergence	A contraction of a vector field; the opposite of divergence
induction	Inference of a generalized conclusion from particular instances
viking	A NASA space probe that gave us the first close look at Mars
mass	Refers to the amount of material found in an object (usually of unit volume).
tolerance model of succession	This model of succession suggests that the change in plant species dominance over time is caused by competition for resources
fathom	The common unit of depth in the ocean for countries using the English system of measurement
graded stream	A stream that has a long profile that is in equilibrium with the general slope of the landscape
celsius	Échelle de température sur laquelle, au niveau de la mer, l'eau a un point de congélation de 0° (Celsius) et un point d'ébullition de +100°
primary producer	Organisms that occupy the first trophic level in the grazing food chain
meteoroid	the term that collectively describes all forms of meteoric material, including meteors and meteorites.
holistic	Concerned with a complete system.
pioneer species	Plant species that dominate a community in the early stages of succession.
convection	Values of CIN typically reflect the strength of the cap
remote sensing	The technology of acquiring data and information about an object without having physical contact with it.
tec	Technical Evaluation Contractor
radial velocity	A type of velocity that expresses motion toward or away from a given location
stilling basin	A basin constructed to dissipate the energy of fast-flowing water (e.g., from a spillway or bottom outlet), and to protect the streambed from erosion.
standard deviation	A statistic that measures the dispersion of a sample.
meniscus	The curved surface of the liquid at the open end of a capillary column.
hypothermia	A rapid, progressive mental and physical collapse that accompanies the lowering of body temperature.
gas	A substance, often invisible, made up of small particles that can expand and contract, and move easily.
refraction	Process where insolation is redirect to a new direction of travel after entering another medium.
aerobic treatment	process by which microbes decompose complex organic compounds in the presence of oxygen and use the liberated energy for reproduction and growth
ceiling	or the height corresponding to the top of a ceiling light projector beam, or the height at which a ceiling balloon disappears during the presence of an indefinite ceiling.
well	an artificial excavation put down by any method for the purposes of withdrawing water from the underground aquifers
remediation	methods used to remove or contain a toxic spill or hazardous materials from a Superfund site; a generic term used to describe cleanup activities.
tropic of cancer	A solstice position of the sun with a latitude 23 degrees 27 minutes N.
knot	a measure of speed equivalent to 1 nautical mile per hour used by the Joint Typhoon Warning Center, which is based in Hawaii.
theory	Proposed explanation for the causal mechanisms responsible for a phenomenon or a set of facts
naturalized conditions	an estimate of natural conditions obtained by attempting to remove effects of human activities from a set of measured conditions.
phreatophyte	A plant that habitually obtains its water supply from the zone of saturation, either directly or through the capillary fringe.
front	The transition zone between two different air masses.
particulate matter	Particles of dust, soot, salt, sulfate compounds, pollen, or other particles suspended in the atmosphere.
continental rise	Thick layers of sediment found between the continental slope the ocean floor.
property protection	Measures that are undertaken usually by property owners in order to prevent, or reduce flood damage
dry line	A boundary separating moist and dry air masses, and an important factor in severe weather frequency in the Great Plains
soil conservation service	The former name of a branch of the United States Department of Agriculture, renamed the Natural Resources Conservation Service (NRCS)
albedo	The percentage of light reflected by an object when it is illuminated.
septic tank	a tank used to detain domestic wastes to allow the settling of solids prior to distribution to a leach field for soil absorption
g-rig	Three pontoons lashed together side by side
permeameter	A laboratory instrument for determining permeability by measuring the discharge through a sample of the material when a known hydraulic head is applied.
beam	The width of a raft at its widest point.
chemical weathering	attack and dissolving of parent rock by exposure to rainwater, surface water, oxygen, and other gases in the atmosphere, and compounds secreted by organisms
imperiled species	declining, rare, or uncommon species; species federally listed as threatened or endangered, or candidates for such; and species with limited distributions.
fungi	Group, at the kingdom level, in the classification of life
precipitation	OXYGEN
macrointervebrate	an animal without a backbone, large enough to be seen without magnification and unable to pass through a 0.595 mm mesh.
channel lead	An elongated opening in the ice cover caused by a water current.
transpiration	Transpiration is the process of water loss from plants through stomata
lava	Molten rock (magma) that extrudes through a volcano
laminar flow	Streamline flow in which successive flow particles follow similar path lines and head loss varies with velocity to the first power.
electrostatics	The charge build up that usually occurs because of electron imbalance at the surface of materials.
ecotone	Boundary zone between two unique community types.
fracture zone	An area which has a great number of fractures.
transpiration	the process by which plants emit water through tiny pores in the underside of their leaves.
silt	Mineral particle with a size between 0.004 and 0.06 millimeters in diameter
small craft advisory	An advisory issued for marine interests, especially for operators of small boats or other vessels
stage iii precipitation processing	The third level of precipitation processing, performed interactively at RFCs
public water use	water supplied from a public-water supply and used for such purposes as firefighting, street washing, and municipal parks and swimming pools.
preliminary damage assessment	A survey to determine the impact and magnitude of damage caused by the disaster and the resulting unmet needs of the public sector and community at large
ice twitch	Downstream movement of a small section of an ice cover
doh	Development and Operations Hydrologist
nrcs	National Resources Conservation Service
portegee	Rowing technique of moving a boat forward by pushing on the oars.
conveyance loss	The loss of water from a conduit due to leakage, seepage, evaporation, or evapo-transpiration.
tectonics	See plate tectonics.
fireline	a strip of land from which all brush and debris have been cleared to rob a wildfire of its fuel
seven-man raft	A boat 6 1/2 by 12 feet that will accommodate three or four people
absorption	The process in which incident radiant energy is retained by a substance
vegetative controls	non-point source pollution control practices that utilize vegetative cover to reduce erosion and minimize loss of pollutants.
succulent vegetation	Group of plants that have the ability to survive in deserts and other dry climates by having no leaves
fte	Full-Time Equivalent
miners' inch	A rate of discharge through an orifice one inch square under a specific head.
hummocked ice	In hydrologic terms, ice piled haphazardly one piece over another to form an uneven surface.
concentrator	a collector that enhances solar energy by focusing it onto a smaller area through mirrored surfaces or lenses.
chlorine contact chamber	the part of a wastewater treatment plant where treated water is disinfected by chlorine.
keystone species	Species that interacts with a large number of other species in a community
validation	The pre-funding verification that proposed or completed work projects meet statutory and regulatory compliance
talus	An accumulation of angular rock debris from rockfalls.
turbine	a machine that uses fluids to turn a wheel or cylinder to create energy, usually electricity
freezing drizzle	Drizzle, the drops of which freeze on impact with the ground or with objects at or near the ground.
project	A logical method of performing work required as a result of the declared event
hydrologic service area	HSA
windblown charge transfer	Charge transfer by the collision of windblown particles with each other or the surface.
morphometry	The measurement of shape
regulatory floodway	Some maps show an area where construction regulations require special provisions to account for this extra hazard
dormant volcano	a volcano that has not erupted for many years.
atmoradiograph	A device for measuring the frequency of occurrence of atmospherics whose intensity is greater than a predetermined level.
ultraviolet radiation	Electromagnetic radiation with a wavelength between 0.1 and 0.4 micrometers (µm).
circum-pacific belt	A zone circling the edge of the Pacific Ocean basin where tectonic subduction causes the formation of volcanoes and trenches
mean sea level	The heights of the sea surface midway between its average high and low water positions.
abutment seepage	Reservoir water that moves through seams or pores in the natural abutment material and exits as seepage.
volcanic crater	a steep-walled depression at the top or on the flank of a volcanic cone, out of which the volcanic materials are ejected
evaporation	the change by which any substance is converted from a liquid state and carried of in vapor
isostatic depression	Large scale sinking of the crust into the asthenosphere because of an increase in weight on the crustal surface
soil creep	the gradual downhill slide of weathered material; the slow, gradual movement of a hill's upper layers caused by the pull of gravity on loose stones, gravel, and soft topsoil
southern oscillation	Reversal of atmospheric circulation in tropical Pacific Ocean that triggers the development of an El Ni隳.
inundation map	A map delineating the area that would be inundated in the event of a dam failure.
electromagnetic radiation	the energy produced by an oscillating electrical (and magnetic) field, transmitted by photons
logarithmic scale	Measurement scale based on logarithms
reflection	Process of returning sound or light waves back to their source.
hypothermia	a condition characterized by a drop in core body temperature from the normal 98.6°F (37.3°C) to 95°F (35.3°C) or lower.
legume	Angiosperm plant species that is a member of the Fabaceae (Pea or Bean) family
frazil slush	An agglomerate of loosely packed frazil which floats or accumulates under the ice cover.
eta	Eta model (now known as the NAM model); one of the operational forecast models run at NCEP with forecast output out to 84 hours (3.5 days).
rock garden	A rapid thickly strewn with exposedor partially covered rocks that demand intricate maneuvering.
oar rubber	Piece of thick rubber used to hold an oar to the thole pin.
veering winds	Winds which shift in a clockwise direction with time at a given location (e.g., from southerly to westerly), or which change direction in a clockwise sense with height (e.g., southeasterly at the surface turning to southwesterly aloft)
niche	Adaptive role that a species has in a habitat
dapm	The Data Acquisition Program Manager.
initial moisture deficiency	The quantity, usually expressed in depth of water in inches upon a unit area, by which the actual water content of a given soil zone (usually the root zone) in such area is less than the field capacity of such zone at the beginning of the rainy season
effective porosity	The ratio, usually expressed as a percentage, of the volume of water or other liquid which a given saturated volume of rock or soil will yield under any specified hydraulic condition, to the given volume of soil or rock.
conveyance loss	water loss in pipes, channels, conduits, and ditches by leakage or evaporation.
calorie	(cal) the amount of energy required to raise the temperature of one gram of water one degree Celsius at 50°C, or 4.1855 joules
proxy data	Data that measures the cause and effect relationship between two variables indirectly.
solar concentrator	a solar collector that enhances solar energy by focusing it onto a smaller area through mirrored surfaces or lenses.
turning point	A temporary point whose elevation is determined by additions and subtractions of backsights and foresights respectively.
nitrogen saturation	Over abundance of nitrogen in natural ecosystems because of human induced inputs related to agriculture and fossil fuel combustion.
cloud	An ensemble of water drops and/or ice particles in the atmosphere above the earth's surface.
pancake ice	Circular flat pieces of ice with a raised rim; the shape and rim are due to repeated collisions.
detritus	Shed tissues, dead body parts, and waste products of organisms
rr	Response and Recovery; also FEMA’s Response and Recovery Directorate
landslides	the falling of masses of earth or rock
geopotential	The potential energy of a unit mass relative to sea level, numerically equal to the work that would be done in lifting the unit mass from sea level to the height at which the mass is located; commonly expressed in terms of dynamic height or geopotential height.
backfire	a small fire set by firefighters in the path of an oncoming wildfire to burn up the fuel before the main fire arrives, thus blocking it.
rain foot	Slang for a horizontal bulging near the surface in a precipitation shaft, forming a foot-shaped prominence
upstream	Toward the source of the flow, or located in the area from which the flow is coming.
specific heat	Is the heat capacity of a unit mass of a substance or heat needed to raise the temperature of 1 gram (g) of a substance 1 degree Celsius.
coral	Simple marine animals that live symbiotically with algae
hod	The Hydrologic Operations Division of the Office of Hydrology (OH).
anticyclone	An area of high atmospheric pressure which has a closed circulation that is anticyclonic (clockwise in northern hemisphere and counterclockwise in southern hemisphere).
progressive succession	Succession where the developing plant community becomes complex and contains more species and biomass over time.
msehpa	Model State Emergency Health Powers Act
biological weathering	The disintegration of rock and mineral due to the chemical and/or physical agents of an organism.
density	The ratio of the mass of a substance to the volume it occupies
direct flood damage	The damage done to property, structures, goods, etc., by a flood as measured by the cost of replacement and repairs.
freezing rain	Rain which falls as liquid then freezes upon impact, resulting in a coating of ice on exposed objects.
convection	Convection involves the transfer of heat energy by means of vertical mass motions through a medium.
mollweide projection	Map projection system that tries to present more accurate representations of area
dip	One of the directional properties of a geologic structure such as a fold or a fault
manning's roughness	a coefficient in Manning's equation that accounts for energy loss due to the friction between the channel and the water
national priorities list	EPA's list of the most serious uncontrolled or abandoned hazardous waste sites identified for possible long-term remedial action under Superfund
hair	Fast, extremely turbulent water covered with white, aerated foam.
active volcano	a volcano erupting or liable to erupt
tetrahedron	Silicon atom joined by four oxygen atoms (SiO4)
sector plate	a starry-shaped snowflake.
ozone	A form of oxygen that has a weak chlorine odor
beginning of the breakup	Date of definite breaking, movement, or melting of ice cover or significant rise of water level.
time	Measurable period in which cause and effect occurs and systems function.
specific heat	The amount of heat required to raise the temperature of 1 gram of a substance by 1 Celsius degree.
nssfc	National Severe Storms Forecast Center, in Kansas City MO; now known as SPC.
unconfined aquifer	Aquifer that is not restricted by impervious layers of rock.
flow-sensitive habitats	habitats that show hydraulic response to relatively small changes in streamflow
periodic table	Table that describes some of the chemical properties of the known elements.
erratic	A large rock boulder that has been transported by glaciers away from its origin and deposited in a region of dissimilar rock.
hurricane local statement	A public release prepared by local National Weather Service offices in or near a threatened area, giving specific details for its county/parish warning area, about (1) weather conditions, (2) evacuation decisions made by local officials, and (3) other precautions necessary to protect life and property.
mass movement	the downhill movement of rock and weathered material
palus	Swamp
boulder garden	A rapid densely strewn with boulders that necessitate intricate maneuvering.
h5	500 millibar level height (in a standard atmosphere this is near 5,500 meters (18,000 ft)
ascii	American Standard Code for Information Interchange
chlorine demand	the difference between the amount of chlorine added to water, sewage, or industrial wastes and the amount of residual chlorine remaining at the end of a specific contact period
cbod	Carbonaceous Biochemical Oxygen Demand. A BOD test in which a nitrification inhibitor is added, so that only the carbonaceous oxygen demanding compounds are measured.
water year	a division based on a general pattern of annual wet and dry periods rather than a calendar year
accuracy rating	A number of quantity defining a limit that errors will not exceed when a device is used under specified operating conditions
hurricane local statement	A public release prepared by local National Weather Service offices in or near a threatened area giving specific details for its county/parish warning area on (1) weather conditions (2) evacuation decisions made by local officials (3) other precautions necessary to protect life and property.
polar axis	Is a line drawn through the Earth around the planet rotates
composite volcano	Volcano created from alternate layers of flows and exploded rock
hydrologic model	A conceptual or physically-based procedure for numerically simulating a process or processes which occur in a watershed.
calorie	The amount of heat needed to raise the temperature of one gram of water one Celsius degree (from 14.5 to 15.5 ·C).
free ground water	water in interconnected pore spaces in the zone of saturation down to the first impervious barrier, moving under the control of the water table slope.
stem antennas	An acronym for Storable Tubular Extendible Member
watershed	Catchment area of a drainage basin.
star	A large and very massive, self-luminous celestial body of gas that illuminates via the radiation derived from its internal source of energy.
deduction	Inference in which the conclusion about particulars follows necessarily from general theory
radioisotope snow gage	A snow water equivalent gage based on the absorption of gamma radiation by snow; this gage can measure up to 55 inches water equivalent with a 2 to 5 percent error.
background level	the concentration of a substance in an environmental media (water or soil) that occurs naturally or is not the result of human activities.
slumping	the slow and gradual slippage of all layers of soil so that the bottom of a hillside becomes level with the lowlands or even tipped upward
special considerations	Factors that must be addressed before federal grant money can be obligated to repair or restore damaged facilities
dew	Condensation in the form of small water drops that forms on grass and other small objects near the ground when the temperature has fallen to the dew point, generally during the nighttime hours.
température du thermomètre sec	La température du thermomètre sec est la valeur lue sur un thermomètre lorsque son réservoir est sec
spray irrigation	an common irrigation method where water is shot from high-pressure sprayers onto crops
toxicity test	the means to determine the toxicity of a chemical or an effluent using living organisms
local flooding	Flooding conditions over a relatively limited (localized) area.
hmgp	Hazard Mitigation Grant Program
bird	Group of warm blooded vertebrate animals whose body is covered with feathers.
boom	A spar to which a sail's lower edge or "foot" is attached
comet	a body in space that has a tail and follows an orbit around the sun.
rock fall	when fragments break away from the face of a steep slope and fall
multiple use	Use of bodies of water for more than one purpose, such as recreational purposes, fishing, and water supply.
genetic adaptation	Changes in the genetic makeup of organisms of a species due to mutations that allow the species to reproduce and gain a competitive advantage under changed environmental conditions.
precipitable water	(also known as PWAT or precipitable water vapour.) The total atmospheric water vapour contained in a vertical column of unit cross-sectional area extending between any two specified levels, commonly expressed in terms of the height to which that water substance would stand if completely condensed and collected in a vessel of the same unit cross section
radiation	The emission of energy from an object in the form of electromagnetic waves and photons.
epri	the Electric Power Research Institute, a research consortium of electric power companies in the United States.
sedimentary rock	rock formed of sediment, and specifically: (1) sandstone and shale, formed of fragments of other rock transported from their sources and deposited in water; and (2) rocks formed by or from secretions of organisms, such as most limestone
air	comprising 0.93% of the total.
inches of runoff	The volume of water from runoff of a given depth over the entire drainage.
great depression	the worst economic collapse in the history of the modern world
conflagration	when a fire burns a large area, sometimes an entire town
population crash	Sudden decline in the number of individuals found in a population because of a scarcity of environmental resources that are required for survival, growth, and reproduction.
absorption	The process by which incident radiant energy is retained by a substance.
digester	in wastewater treatment, a unit in which anaerobic bacterial action is induced and accelerated in order to break down and stabilize organic matter removed from the treatment process.
cooling degree day	A cooling degree day is given for each degree that the daily mean temperature departs above the baseline of 75 degrees a given temperature It is used to estimate the energy requirements, and is an indication of fuel consumption for air conditioning or refrigeration
igneous rock	rock made of solidified molten material that made its way from the interior of the planet to the surface.
sanitary sewers	underground pipes that carry off only domestic or industrial waste, not storm water.
suspended-sediment discharge	the quantity of suspended sediment passing a point in a stream over a specified period of time
visibility	The greatest distance an observer can see and identify prominent objects.
trophic pyramid	A graphic model describing the distribution of energy, biomass, or some other measurable quantity between the different trophic levels found in an ecosystem.
stream segment	Refers to the surface waters of an approved planning area exhibiting common hydrological, natural, physical, biological, or chemical processes
seed dispersal	Movement of a plant seed away from the parent plant by a passive or active mechanism.
force	Process that changes the state of rest or motion of a body.
reg	A rocky desert landscape
desalination	the removal of salts from saline water to provide freshwater
fire fountain	a jet of magma spouting from a narrow volcanic vent
surface fire	a fire with a visible flame that consumes plant material and debris on the forest floor.
pathogen	Microscopic parasite organism that causes disease in a host
sinusoidal equal-area projection	Map projection that represents areas in their true form on a two-dimensional map
frost creep	Slow mass movement of soil downslope that is initiated by freeze-thaw action
cytoplasm	All of the protoplasm in a cell except for what is contained in the nucleus.
toe drain	A drain which carries seepage away from the dam and can allow seepage quantities to be measured.
threesome raft	Three rafts lashed together side by side
topography	The configuration of a surface, including its relief and the position of its natural and man-made features.
geologic time	A span of millions or billions of years in the past.
ice bridge	A continuous ice cover of limited size extending from shore to shore like a bridge.
mesa	A flat topped hill that rises sharply above the surrounding landscape
phytoplankton	Small photosynthetic organisms, mostly algae and bacteria, found inhabiting aquatic ecosystems
equi-potential line	A line, in a field of flow, such that the total head is the same for all points on the line, and therefore the direction of flow is perpendicular to the line at all points.
tropical depression	An organized group of thunderstorms often found over a tropical ocean that generates a cyclonic flow of between 37 and 63 kilometers per hour
meteorite	It's a meteor that reaches the Earth's surface.
floc	A cluster of frazil particles.
continental plate	A rigid, independent segment of the lithosphere composed of mainly granite that floats on the viscous plastic asthenosphere and moves over the surface of the Earth
clinometer	An instrument used to measure angles of inclination
movement	A term used in geography that deals with the migration, transport, communication, and interaction of natural and human-made phenomena across the spatial dimension.
evaporation rate	The quantity of water, expressed in terms of depth of liquid water, which is evaporated from a given surface per unit of time
noctilucent clouds	Rarely seen clouds of tiny ice particles that form approximately 75 to 90 kilometers above the earth's surface
isopleth	General term for a line connecting points of equal value of some quantity
sewage	The waste and wastewater produced by residential and commercial sources and discharged into sewers.
public information officer	A person appointed by a County Emergency Operations Center to be responsible for the formulating and coordinating of the dissemination of emergency public information with both the electronic and written media, ensuring that accurate information is being released to the general public
alkalinity	the measurement of constituents in a water supply which determine alkaline conditions
clastic sedimentary rock	Sedimentary rocks that are formed by the lithification of weathered rock debris that has been physically transported and deposited.
isentropic surface	A two-dimensional surface containing points of equal potential temperature.
organ	Group of cells and tissues that have a particular function for an organism.
secondary consumer	Organisms that occupy the third trophic level in the grazing food chain
sand sheet	Deposit of sometimes stratified less well sorted sand that almost resemble dunes
magnetic field	The space influence by magnetic force
foreshock	Small earth tremors that occur seconds to weeks before a significant earthquake event.
groundwater law	the common law doctrine of riparian rights and the doctrine of prior appropriation as applied to ground water.
ionosphere	The uppermost atmospheric shell characterized by a high ion density.
albedo	The portion of incoming radiation which is reflected by a surface.
seismic waves	(pronounced SIZE-mic waves) vibrations that move outward from the focus of an earthquake, causing the ground to shake.
sulfur dioxide	A gas produced from volcanic eruptions, ocean spray, organic decomposition and the burning of fossil fuels
eolian	Geomorphic process involving wind
fissionable isotope	Isotope that can undergo nuclear fission when hit by a neutron at the right speed
halo	Groups of optical phenomena, in the form of rings, arcs, pillars or bright spots, produced by the refraction or reflection of light by ice crystals suspended in the atmosphere.
kinetic energy	The energy within a body that is a result of its motion.
sand filters	devices that remove suspended solids from a wastewater treatment plant effluent or water treatment plant product.
opisometer	Mechanical device for measuring non-linear distances on maps.
corona	Colored rings about the moon or sun; due to diffraction of light by spherical cloud droplets.
potable water	water of a quality suitable for drinking.
desalination	the process of salt removal from sea or brackish water.
law of stream number	Morphometric relationship observed in the number of stream segments of a particular classification order in stream channel branching
mast	The vertical spar that holds up the sails.
high latitudes	With specific reference to zones of geomagnetic activity, "high latitudes" refers to 50º to 80º geomagnetic.
public information officer	A person appointed by a County Emergency Operations Center to be responsible for the formulating and coordinating of the dissemination of emergency public information with both the electronic and written media, ensuring that accurate information is being released to the general public.
palsa	A mound of peat that develops as the result of the formation of a number ice lenses beneath the ground surface
solvent	a substance that dissolves other substances, thus forming a solution
nitrogen dioxide	A gas produced by bacterial action in the soil and by high temperature combustion
magnetosphere	Zone that surrounds the Earth that is influenced by the Earth's magnetic field.
bush	open forest land
climatology	The study of climate and its controls and variability.
pulaski	a combination ax and hoe that is used by firefighters to clear brush and create a fire line
calibration	The process of using historical data to estimate parameters in a hydrologic forecast technique such as SACSMA, routings, and unit hydrographs.
ice pellets	Frozen raindrops that bounce on impact with the ground; also called sleet.
nitrification	The biochemical oxidation of ammonium to nitrite and nitrite to nitrate
ns	FEMA’s Office of National Security Affairs
parts per million	the number of "parts" by weight of a substance per million parts of water
injection well	refers to a well constructed for the purpose of injecting treated wastewater directly into the ground
mountain breeze	Local thermal circulation pattern found in areas of topographic relief
sleet	precipitation which is a mixture of rain and ice.
litter	Accumulation of leaves, twigs and other forms of organic matter on the soil surface
feldspar	A group of common aluminum silicate minerals that contains potassium, sodium, or calcium.
partial-duration flood series	A list of all flood peaks that exceed a chosen base stage or discharge, regardless of the number of peaks occurring in a year
coagulation	in water treatment, the use of chemicals to make suspended solids gather or group together into small flocs.
bed	Sedimentary structure that usually represents a layer of deposited sediment.
rock	A compact and consolidated mass of mineral matter
isobath	An imaginary line on the earth's surface or a line on a map connecting all points which are the same vertical distance above the upper or lower surface of a water-bearing formation or aquifer.
imhoff cone	a clear, cone-shaped container used to measure the volume of settleable solids in a specific volume of water.
notification	To inform appropriate individuals about an emergency condition so they can take appropriate action
fsn	FEMA Switch Network
biogeochemical	Key chemical constituents essential to life
slab avalanche	avalanche that begins when fracture lines develop in a snowpack and a large surface plate breaks away, then crumbles into blocks as it falls down a slope.
elevation	The measure of height with respect to a point on the earth's surface above mean sea level
radiation	The process by which energy is propagated through any medium by virtue of the wave motion of that medium
competition	Interaction where two or more organisms in the same space require the same resource (e.g., food, water, nesting space, and ground space) which is in limiting supply to the individuals seeking it
horizon	One of several lines or planes used as reference for observation and measurement relative to a given location on the surface of the earth
density	The ratio of the mass of a substance to the volume it occupies.
cinder	a small piece of material thrown from a volcano during an eruption.
pillow	The layer of slack water that pads the upstream face of rooks andother obstructions
subatomic particles	Extremely small particles that make up the internal structure of atoms.
oxygen demand	the need for molecular oxygen to meet the needs of biological and chemical processes in water
mare's tail	The name given to thin, wispy cirrus clouds composed of ice crystals that appear as veil patches or strands, often resembling a horse's tail.
ftp	A method of data transfer that can take place between Frame Relay Networks, and Workstations.
ion	An atom, molecule or compound that carries either a positive (cation) or negative (anion) electrical charge.
ionizers	A device that charge the air creating ions that increases its conductivity.
oceanography	it is the abrupt change or jump of a variable at a line or surface.
insect	Relatively small and simple animals that have a rigid external skeleton, three body sections, three pairs of legs, and antennae
river observing station	An established location along a river designated for observing and measuring properties of the river.
composite volcano	a volcano with steep sides made of layers of lava and ash.
kilogram	one thousand grams.
tropics	The area between the Tropics of Cancer and Capricorn
clarification	the clearing action that occurs during wastewater treatment when solids settle out
inflow	entry of rainwater into a sewer system from sources other than infiltration, such as basement drains, manholes, storm drains, and street washing.
anti-degradation clause	part of federal and water quality requirements prohibiting deterioration where pollution levels are above the legal limit.
satellite	STM
chloroplast	Organelle in a cell that contains chlorophyll and produces organic energy through photosynthesis.
random	Process or event that occurs by chance.
meteor shower	An event when hundreds of meteors or shooting stars appear in the sky at a specific time.
disaster	a manifestation of an interaction between extreme physical or natural phenomena and a vulnerable human group that results in general disruption and destruction, loss of life and livelihood and injury (Tilling, Volcanic Hazards, fig
intrusive igneous rock	A mass of igneous rock that forms when magma from the mantle migrates upward and cools and crystallizes near, but not at, the Earth's surface
shefpars	A software decoder for SHEF Data.
tissue	A group of similar cells that are organized into a structure with a specific purpose.
watt	A unit of power or energy per unit time.
fault	A fracture in rock caused by stress.
polygenetic landform	Landform that shows the influence of two or more major geomorphic processes
enzyme	Are types of proteins that are used to facilitate and regulate chemical reactions within cells.
radionuclide	a radioactive particle, man-made or natural, with a distinct atomic weight number
calcification	A dry environment soil-forming process that results in the accumulation of calcium carbonate in surface soil layers.
red flag warning	A warning issued when conditions are favorable for the rapid spread of wildfires.
mafic magma	Magma that is relative poor in silica but rich in calcium, magnesium, and iron content
basement rock	Very old granite and metamorphic rocks found in continental crust
isobar	Lines on a map joining points of equal atmospheric pressure.
curtain drain	A drain constructed at the upper end of the area to be drained, to intercept surface or ground water flowing toward the protected area from higher ground, and carry it away from the area
asthenosphere	region of the mantle below the lithosphere, composed of partially melted rock.
nautical mile	A unit of length used in marine navigation that is equal to one minute of arc of a great circle on a sphere
generalist species	Species that can survive and tolerate a broad range of environmental conditions.
scientific method	The approach science uses to gain knowledge
belay	To wrap a line around a rock or tree so as to slow or stop Slippage
moisture content	the amount of water lost from soil upon drying to a constant weight, expressed as the weight per unit of dry soil or as the volume of water per unit bulk volume of the soil.
transmitter	The radar equipment used for generating and amplifying a radio frequency (RF) carrier signal, modulating the carrier signal with intelligence, and feeding the modulated carrier to an antenna for radiation into space as electromagnetic waves
solution	a mixture of a solvent and a solute
air	it is the difference between the dry bulb and the wet bulb readings.
elastic wave	An energy wave that causes elastic deformation in a material without its structure and shape being deformed.
air pollution	The soiling of the atmosphere by contaminants to the point that may cause injury to health, property, plant, or animal life, or prevent the use and enjoyment of the outdoors.
return flow	irrigation water that is applied to an area and which is not consumed in evaporation or transpiration and returns to a surface stream or aquifer.
reflectivity	The measure of the efficiency of a radar target in intercepting and returning Electro Magnetic Energy
altitude	A measure of height of an object, usually with reference to the earth's surface, or sea level.
below	Downriver from.
squall line	A band of thunderstorm development found ahead of a cold front.
lowland flooding	Inundation of low areas near the river, often rural, but may also occur in urban areas.
rotation	The spinning of a body, such as the earth, about its axis.
fire triangle	the combination of three elements required for any fire: fuel, oxygen, and heat.
freeze-thaw action	Processes associated with daily and seasonal cycles of freezing and melting.
rtf	Response Task Forces
coriolis force	A force that deflects moving objects to one side because of the Earths rotation
*tornado	A violently rotating column of air in contact with the ground and extending from the base of a thunderstorm
ozone	Molecule made up of 3 oxygen atoms
heredity	The transmission of behavioral, physiological and morphological characteristics from parent to offspring.
in-situ oxidation	technology that oxidizes contaminants dissolved in groundwater, converting them into insoluble compounds.
climate change	Variations in climate ranging from decades to geological time scales.
regosol soil	Soil order (type) of the Canadian System of Soil Classification
ionosphere	A region in the atmosphere above 50 kilometers from the surface where relatively large concentrations of ions and free electrons exist
po	Purchase Officer
metasomatic metamorphism	Form of metamorphism that causes the chemical replacement of elements in rock minerals when gases and liquids permeate into bedrock.
frost	a covering of minute ice crystals on a cold surface.
chemical reaction	Reaction between chemicals where there is a change in the chemical composition of the elements or compounds concerned.
breakpoint chlorination	addition of chlorine to the point where all organic matter and ammonia compounds have been destroyed and any additional chlorine becomes a free chlorine residual available for disinfection.
sublimation	The process of ice changing phase into vapor.
solar thermal electric	technology for using the sun's energy to produce steam to run turbines that generate electricity.
muscovite	Rock forming mineral of the mica group.
visibility	A measure of the opacity of the atmosphere, and therefore, the greatest distance one can see prominent objects with normal eyesight
insolation	it is responsible for many complex photochemical reactions, such as fluorescence and the formation of ozone.
protista	Group, at the kingdom level, in the classification of life
leachate	Solution containing material leached from a soil.
environment	aggregate of external conditions that influence the life of an individual organism or population.
water quality-based toxics control	an integrated strategy used in NPDES permitting to assess and control the discharge of toxic pollutants to surface waters
cinder cone	a volcano made of lava fragments.
mass movement	General term that describes the downslope movement of sediment, soil, and rock material.
atmosphere	EL
median particle size	value for which half the particles in a sample have a greater diameter and half a lesser diameter.
hurricane clips	A structural bracing device used on the installation of roofs which reinforce the joints of a house and give a stronger connection to wood-to-wood roofing trusses than just nails
ice push	Compression of an ice cover particularly at the front of a moving section of ice cover.
exogenic	Refers to a system that is external to the Earth.
dendrites	Thin branch-like growth of ice on the water surface.
slope failure	The downslope movement of soil and sediment by processes of mass movement.
robinson projection	Map projection system that tries to present more accurate representations of area
hwvr	However
free ground water	Unconfined ground water whose upper boundary is a free water table.
lfws	A generic term for any type of Local Flood Warning System.
evaporation	The process of changing a liquid (like water) to a vapor
wildfire	a large, uncontrolled fire in grass, brush, or trees.
groundwater recharge	The replenishment of groundwater with surface water.
pressure head	Energy contained by fluid because of its pressure, usually expressed in feet of fluid (foot pounds per pound).
optimum	The level of an abiotic factor or condition in the environment within the tolerance range at which a species or population can function most efficiently or with the greatest positive effect to its physiological or reproductive fitness.
montmorillonite	A type of clay that has a large capacity to shrink and expand with wetting and drying.
initial water deficiency	The quantity, usually expressed in depth of water in inches upon a unit area, by which the actual water content of a given soil zone (usually the root zone) in such area is less than the field capacity of such zone at the beginning of the rainy season
precipitable water	The total atmospheric water vapor contained in a vertical column of unit cross-sectional area extending between any two specified levels, commonly expressed in terms of the height to which that water substance would stand if completely condensed and collected in a vessel of the same unit cross-section
green river boat	A raft 8 by 17 feet made by Rubber Fabricators that can accommodate five or six people.
food web	A model describing the organisms found in a food chain
gene	Each form produces a unique inheritable characteristic.
anaerobic	a life or process that occurs in, or is not destroyed by, the absence of oxygen.
shear	Its just a variation in the wind speed and/or direction over a short distance.
hinge crack	In hydrologic terms, a crack caused by significant changes in water level.
bilge	The lowest part of a boat's hull.
nsa	National Security Agency
vibration	a continuous shaking movement
loose-snow avalanche	avalanche composed of loosely packed snow that begins at a single point and slides down a slope, fanning out in the shape of an inverted "V."
meander belt	The area between lines drawn tangential to the extreme limits of fully developed meanders.
precipitate	Solidification of a previously dissolved substance from a solution.
falsification	Falsification is a procedure used in science to test the validity of a hypothesis or theory
unstable equilibrium	In an unstable equilibrium the system returns to a new equilibrium after disturbance.
arctic	Of or relating to the area around the geographic North Pole, from 90° North to the Arctic Circle at approximately 66 1/2 North latitude.
plug	a tower of hard rock left by a volcano
lindane	a pesticide that causes adverse health effects when present in domestic water supplies and is toxic to freshwater fish and aquatic life.
nohrsc	The National Operational Hydrologic Remote Sensing Center
divergence	This is an area where winds/windfields diverge
meteor	Its a shooting star
thickness	The height difference between two atmospheric pressure levels and is related to the average temperature in the column.
nonpoint source	source of pollution in which wastes are not released at one specific, identifiable point but from a number of points that are spread out and difficult to identify and control
radar echo	The energy scattered back from a target and detected by the radar receiver
gar	Governor’s Authorized Representative
pivot	Turning the raft from a ferry angle to a bow-downstream Position
ngvd of 1929	National Geodetic Vertical Datum of 1929
hsb	The Hydrologic Systems Branch in the Office of Hydrology (OH).
fire weather watch	Conditions are expected to become favorable for the rapid spread of wildfires.
rating table	A table of stage values and the corresponding discharge for a river gaging site.
pitted topography	Landscape characterized by numerous kettle holes on a glacial outwash plain.
savannah	Open tropical grassland with few trees.
metric	A system of weights and measures based upon the meter and kilogram.
retrofitting	installing modern pollution control devices at facilities without making major changes to the facility's design.
reverse osmosis	(1) (Desalination) The process of removing salts from water using a membrane
icicle	Ice that forms in the shape of a narrow cone hanging point down
freeze	A condition occurring over a widespread area when the surface air temperature remains below freezing for a sufficient time to damage certain agricultural crops.
gc	FEMA’s Office of General Counsel
resource	Anything obtained from the environment to meet the needs of a species.
moisture equivalent	The ratio of (1) the weight of water which the soil, after saturation, will retain against a centrifugal force 1,000 times the force of gravity, to (2) the weight of the soil when dry
sidereal day	Time it takes to complete one Earth rotation relative to the position of a fixed star
vertical temperature profile	A series of temperature measurements taken at various levels in the atmosphere that show the thermal structure of the atmosphere over a specific location
variance	A statistical measure of the dispersion of observation values in a data set
sedimentary rock	Rocks formed by the deposition, alteration and/or compression, and lithification of weathered rock debris, chemical precipitates, or organic sediments
stratiform	Having extensive horizontal development, as opposed to the more vertical development characteristic of convection
refraction	The process in which the direction of energy propagation is changed due to spatial variations in properties (e.g
volcano	an opening in Earth's surface through which gases, hot rocks, and ash are ejected from the heated inner portion of the planet.
macroburst	A large downburst affecting an area more than 4 kilometers (about 2.5 miles) across with damaging winds lasting from 5 to 20 minutes
andes	mountain range extending more than 5,000 miles (8,045 kilometers) along the western coast of South America.
drought	A period of abnormally dry weather sufficiently long enough to cause serious effects on agriculture and other activities in the affected area.
spring tide	Tide that occurs every 14 to 15 days and coincides with the new and full moon
biotite	Rock forming mineral of the mica group.
friction head	The decrease in total head caused by friction.
filter	a device used to remove solids from a mixture or to separate materials
heating degree days	(abbrev
thermodynamic equilibrium	This type of equilibrium describes a condition in a system where the distribution of mass and energy moves towards maximum entropy.
wave-cut notch	A rock recess at the foot of a sea cliff where the energy of water waves is concentrated.
oh	The Office of Hydrology, located in Silver Springs, MD.
french drain	An underground passageway for water through the interstices among stones placed loosely in a trench.
half-life	Time required for one half of the nuclei in a radioisotope to emit its radiation
organisation météorologique mondiale	Étant donné que les systèmes météorologiques et les conditions climatiques dépassent les frontières internationales, il est nécessaire que l'information météorologique puisse être échangée librement et gratuitement dans le monde entier
snowburn	A burn of the skin, like a sunburn, but caused by the sun's rays reflected off the snow surface.
atmosphere	A layer of gases surrounding a planet
hazard	Phenomenon which can cause loss of life, injury, disease, economic loss, or environmental damage.
updraft	Tornadoes may develop from wall clouds attached to the rain-free base, or from the rain-free base itself - especially when the rain-free base is on the south or southwest side of the main precipitation area
afos	Automation of Field Operations and Services
detrital rock	Sedimentary rock that is composed of particles transported to their place of deposition by erosional processes
pry stroke	paddling technique of moving a boat sideways away from the paddle
dissociation	Chemical process where a compound or molecule breaks up into simpler constituents.
hotshot	a specialized firefighter who ventures in to hazardous areas and spends long hours battling blazes.
ntsp	National Plan for Telecommunications Support in Non-Wartime Emergencies
theta-e ridge	An axis of relatively high values of theta-e
dust bowl	the popular name for the approximately 150,000 square-mile-area (400,000-square-kilometer-area) in the southern portion of the Great Plains region of the United States
assay	a test for a specific chemical, microbe, or effect.
front	The line that separates warm and cold fronts
radar	a system that locates distant objects by sending out radio waves and detecting them when they bounce back off the objects
standard atmosphere	A standard atmosphere has been defined by the International Civil Aeronautical Organization (ICAO)
histosols	Soil order (type) of the United States Natural Resources Conservation Service Soil Classification System
isoline	Lines on a map joining points of equal value.
ppc	Prevention Preparedness Council
convection	The transfer of energy by the movements of masses in a liquid or a gas
kirchoff's law	This law suggests that good emitters of radiation are also good absorbers of radiation at specific electromagnetic radiation wavelength bands
weather	day to day variation in atmospheric conditions
force account	An applicant's own labor forces and equipment
perched water table	The water table of a relatively small ground-water body supported above the general ground water body.
solum	Part of the soil that is capable of supporting life.
lipid	Is an organic compound composed of carbon atoms that have two hydrogen atoms attached
two-ribbon flare	In solar-terrestrial terms, a flare that has developed as a pair of bright strands (ribbons) on both sides of the main inversion ("neutral") line of the magnetic field of the active region.
taxonomic classification	Classification of organisms based on structural and physiological connections between other species.
marine	With reference to ocean environments and processes.
fern	A group of about 11,000 species of vascular seedless plants that belong to the division Pterophyta
volatile organic compounes	a group of chemicals that react in the atmosphere with nitrogen oxides, heat and sunlight to form ozone; VOCs are referred to as hydrocarbons.
technology-based treatment requirements	NPDES permit requirements based on the application of pollution treatment or control technologies including BTP (best practicable technology), BCT (best conventional technology), BAT (best available technology economically achievable), and NSPS (new source performance standards).
hydrograph separation	In hydrologic terms, the process where the storm hydrograph is separated into baseflow components and surface runoff components.
biological oxidation	decomposition of complex organic materials by microorganisms
shrub	A woody plant species that is smaller than a tree
artificial recharge	an process where water is put back into ground-water storage from surface-water supplies such as irrigation, or induced infiltration from streams or wells.
vertical visibility	The distance an observer can see vertically into an undefined ceiling, or the height corresponding to the top of a ceiling light projector beam, or the height at which a ceiling balloon disappears during the presence of an indefinite ceiling.
basic	Substance having a pH greater than 7.
radar	An electronic instrument, which determines the direction and distance of objects that, reflect radio energy back to the radar site
wetlands	land, such as a bog or marsh, that has wet and spongy soil
dalton’s law	A scientific law that states that the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of each constituent gas.
sun	Luminous star around which the Earth and other planets revolve around
atmospheric windows	Infrared wavelength bands within which there is little or no absorption by the major greenhouse gases (e.g., H20, CO2, O3).
equilibrium	A condition in which all acting influences are canceled by others, resulting in a stable, balanced, or unchanging system.
photosynthesis	The process whereby plants use sunlight, water, and carbon dioxide to manufacture their food and generate oxygen as a byproduct.
longitude	Longitude is a west-east measurement of position on the Earth
cumulus cloud	A cloud in the shape of individual detached domes, with a flat base and a bulging upper portion resembling cauliflower.
casing	a tubular structure intended to be watertight installed in the excavated or drilled hole to maintain the well opening and, along with cementing, to confine the ground waters to their zones of origin and prevent the entrance of surface pollutants.
hurricane watch	issued as a warning sign to people while the hurricane is still at sea; intended to tell people of the hurricane risk and possibility of disaster
theory	a belief explaining something, backed by certain facts
ground moraine	A thick layer of till deposited by a melting glacier.
asteroid	a rocky chunk of matter in orbit around the sun.
control system	A system that is intelligently controlled by the activities of humans
diabatic process	A process in a thermodynamic system in which there is a transfer of heat across the boundaries of the system.
big crunch	Collapse of the Universe into its original form before the Big Bang
infrared radiation	radiation with wavelengths greater than those of the visible light (at about 8000 Angstroms or 800 nanometers(nm)) but shorter than those of microwaves (at about 1,000,000 Angstroms or 800,000 nm)
species association	A particular grouping of species in an area.
median	Statistical measure of central tendency in a set of data
longitude	Les coordonnées de longitude données pour les stations climatologiques sont généralement celles du parc des instruments; cependant, avant le 1 avril 1986, pour les stations principales (aéroports), on indiquait normalement l'emplacement officiel de ces aéroports
mesoscale	Size scale referring to weather systems smaller than synoptic-scale systems but larger than storm-scale systems
cohesion	a molecular attraction by which the particles of a body are united throughout the mass whether like or unlike
population density	Number of individuals of a particular species found in a specified area.
scar	A rock formation on the side of a mountain.
hv	have
clear-cutting	the logging practice of harvesting all trees from vast forest tracts.
laminar	Smooth, non-turbulent
galaxy	An assemblage of millions to hundreds of billions of stars.
roche moutonnee	A feature of glacial erosion that resembles an asymmetrical rock mound
major flooding	A general term including extensive inundation and property damage
hair hygrometer	An instrument designed to monitor relative humidity by measuring the changes in the length of human hair that accompany humidity variations.
mons pl. montes	A standard IAU feature name, taken from the Latin mons meaning mountain.
hydration	A form of chemical weathering that involves the rigid attachment of H+ and OH- ions to the atoms and molecules of a mineral.
dendritic	Term used to describe the stream channel pattern that is completely random
gate	Narrow, short passage between two obstacles.
conservation	to protect from loss and waste
mycorrhizae	Mutualistic association of a fungus with the root of higher plant
chelation	Chemical weathering process that involves the extraction or metallic cations from rocks and minerals by chelates.
electromagnetic radiation	Also called radiation, it is waves of energy propagated though space or through a material media.
fitness	A measure of the health of a species in terms of physiology and future reproductive success.
ahos-t	Automatic Hydrologic Observing System - Telephone
entropy	Entropy is the measure of the disorder or randomness of energy and matter in a system.
temporal	pertaining to time, such as temporal variation (variation over time).
extinct volcano	volcanoes no longer liable to erupt
mode	Statistical measure of central tendency in a set of data
wave length	The least distance between particles moving in the same phase of oscillation of a wave
tropical disturbance	An area of organized convection, originating in the tropics and occasionally the subtropics, that maintains its identity for 24 hours or more
subsidence	Sinking (downward) motion in the atmosphere, usually over a broad area.
pangea	The primeval continental mass
chemical	One of the millions of different elements and compounds found naturally and synthesized by humans.
earthflow	when the wet ground breaks up and falls down a mountainside, making a rounded, tongue-like shape; usually occurs on clay, silt, or sand; the slowest, driest flow of weathered material down a hillside
unit hydrograph duration	The time over which one inch of surface runoff is distributed for unit hydrograph theory.
freezing	The change in state of matter from liquid to solid that occurs with cooling
continental glacier	Largest type of glacier with a surface coverage in the order of 5 million square kilometers.
chromosome	Organic structure that carries an organism's genetic code (DNA).
diversity	See Species Diversity.
richter scale	the scale developed by American seismologist Charles Richter that describes the amount of energy released by an earthquake on a scale from 1 to 10
polar front	Transition zone between cold polar easterlies and mild midlatitude westerlies.
banned woods	an area of woodland in an avalanche zone, which cannot be cut or disturbed because it is a natural barrier to avalanches
jiise	Joint Interagency Intelligence Support Element
cloud	A group of suspended water and/or ice particles in the air.
hygroscopic water	Water held within 0.0002 millimeters of the surface of a soil particle
topographic profile	A two-dimensional diagram that describes the landscape in vertical cross-section.
swedish viking	A scientific satellite launched in February 1986
ensemble hydrologic forecasting	A process whereby a continuous hydrologic model is successively executed several times for the same forecast period by use of varied data input scenarios, or a perturbation of a key variable state for each model run
taxon	A classification category for a group of organisms.
identification de tc	L'identificateur de Transports Canada est l'indicatif attribué par Transports Canada pour identifier les rapports mátéorologiques provenant des stations localisés aux aéroports et transmis en temps réel dans des formats d'aviation.
stratosphere	Atmospheric layer found at an average altitude of 11 to 50 kilometers above the Earth's surface
nitrogen cycle	Product of organic matter decomposition
its	FEMA’s Information Technology Services Directorate
boulder	Large fragment of rock that has a diameter greater than 256 millimeters (200 millimeters in the United Kingdom).
wastewater	water that has been used in homes, industries, and businesses that is not for reuse unless it is treated.
greenhouse effect	The overall warming of the earth's lower atmosphere primarily due to carbon dioxide and water vapor which permit the sun's rays to heat the earth, but then restrict some heat-energy from escaping back into space.
thermoelectric power water use	water used in the process of the generation of thermoelectric power
stefan-boltzmann law	A fundamental radiation law a that states that the total energy emitted by a blackbody is proportional to the fourth power of its temperature.
effluent	water that flows from a sewage treatment plant after it has been treated.
cumulonimbus	A cumulus type of deep vertical extent, often reaching in excess of 30000ft
greenhouse effect	The heating of the planet that results from the fact that the atmosphere absorbs and emits infrared radiation.
meridional flow	A term used when describing the upper air pattern
rock cycle	General model describing the geomorphic and geologic processes involved in the creation, modification and recycling of rocks.
galloway position	Basic position for oar boats; the oarsman faces the bow, which is pointed downstream.
liquefaction	Temporary transformation of a soil mass of soil or sediment into a fluid mass
hr	Hour
hydraulic radius	The right cross-sectional area of a stream of water divided by the length of that part of its periphery in contact with its containing conduit; the ratio of area to wetted perimeter
synoptic	Pertaining to an overall view.
cave	A natural cavity or recess that is roughly positioned horizontally to the surface of the Earth.
particle size	the diameter, in millimeters, of suspended sediment or bed material
volatilization	The process where a solid or liquid substance is converted into a gas.
stable equilibrium	In a stable equilibrium the system displays tendencies to return to the same equilibrium after disturbance.
magma chamber	a cavity beneath a volcano where magma collects
trophic structure	the feeding relationships among species within a food web.
convection	originating in the tropics and occasionally the subtropics, that maintains its identity for 24 hours or more
longshore transport	The transport of sediment in water parallel to a shoreline.
recession constant	Constant used to reduce the API value daily in the API method of estimating runoff.
ozone	A nearly colorless gas and a form of oxygen (O2)
quicksand	a mass of loose, wet sand that becomes fluid when suddenly vibrated; heavy objects will sink into it
radiosonde	a balloon carrying instruments for measuring conditions in the upper atmosphere
isotherm	line that connects points of equal temperature.
mass extinction	A catastrophic, widespread perturbation where major groups of species become extinct in a relatively short time compared to normal background extinctions.
sinking	controlling oil spills by using an agent to trap the oil and sink it to the bottom of the body of water where the agent and the oil are biodegraded.
hinge crack	Crack caused by significant changes in water level.
thermopile	a set of thermocouple junctions connected in series in order to boost the voltage to a meaningful amount (usually measured in millivolts)
climate	Weather of some locality averaged over some time period plus extremes in weather behavior observed during the same period or during the entire period of record.
rainbow	An arc of concentric colored bands that spans a section of the sky when rain is present and the sun is positioned at the observer's back.
reverse ferry	A rowing technique whereby the oarsman rows diagonally downstream for a short distance so as to power stern first into an eddy
newton	The unit of force giving a mass of about one kilogram (2.205 pounds) an acceleration of about one meter (1 yard) per second per second.
gravitational pull	the force that draws all bodies in the universe toward one another
smoker	An extremely violent rapid; hair.
air density	The ratio of the mass of a substance to the volume it occupies
longitude	The location east or west in reference to the Prime Meridian, which is designated as zero (0) degrees longitude
sundogs	Also called parhelion
three-hour rainfall rate	This WSR-88D Radar product displays precipitation total (in inches) of the current and past two clock hours as a graphical image
mmrs	Metropolitan Medical Response System
carbon adsorption	a treatment system that removes contaminants from ground water or surface water by forcing it through tanks containing activated carbon treated to attract the contaminants.
retrogressive succession	Succession where the plant community becomes simplistic and contains fewer species and less biomass over time.
souse hole	A hole found below an underwater obstruction, such as a boulder
specific heat	The amount of energy needed to raise the temperature of one gram of a substance one degree Celsius.
bacteria	Simple single celled prokaryotic organisms
pumice	volcanic rock formed during the explosive eruption of magma; it has numerous gas bubbles and floats on water.
water column	an imaginary column extending through a water body from its floor to its surface
deep well	A well whose pumping head is too great to permit use of a suction pump.
habitat	Location where a plant or animal lives.
demand	the number of units of something that will be purchased at various prices at a point in time
universal time coordinate	One of several names for the twenty-four hour time that is used throughout the scientific and military communities
watershed	The area of land where all of the water that is under it or drains off of it goes into the same place (Source: Environmental Protection Agency).
molecule	Minute particle that consists of connected atoms of one or many elements.
coevolution	The coordinated evolution of two or more species that interact and exert selective pressures on each other that can cause each species to undergo associated adaptations
deuterium	Isotope of hydrogen, with a nucleus containing one proton and one neutron, and an atomic mass number of 2.
sfip	Standard Flood Insurance Policy
sleet	A type of precipitation consisting of transparent pellets of ice 5 millimeters or less in diameter
fen	Flat, low-lying, marshy ground.
indicator parameters	measurable physical or chemical characteristics or attributes of water or soil-pore moisture used to indicate the possible presence of waste constituents, or the effects of waste constituents on waters.
protein	Organic substances primarily composed of carbon, hydrogen, nitrogen, and some other minor elements which are arranged in about 20 different compounds known as amino acids
dispersal	An organism leaving its place or birth or activity for another location.
percolation	(1) The movement of water through the openings in rock or soil
reference map	Map that shows natural and human-made objects from the geographical environment with an emphasis on location
patterned ground	Term used to describe a number of surface features found in periglacial environments
friction	Resistance between the contact surfaces of two bodies in motion.
inversion	which is marked by the unusually uniform height of the clouds
littoral zone	The zone along a coastline that is between the high and low-water spring tide marks.
hrl	The Hydrological Research Laboratory at the Office of Hydrology (OH).
recycled water	water that is used more than one time before it passes back into the natural hydrologic system.
well	a bored, drilled, or driven shaft or a dug hole whose depth is greater than the largest surface dimension and whose purpose is to reach underground water supplies or oil or to store or bury fluids below ground.
conventional radar	instrument that detects the location, movement, and intensity of precipitation, and gives indications about the type of precipitation
dissolved solids	inorganic material contained in water or wastes
endogenic	Refers to a system that is internal to the Earth.
primary consumer	Organisms that occupy the second trophic level in the grazing food chain
sunspots	dark, relatively cool areas on the surface of the sun
geographic isolation	See spatial isolation.
mesoscale	The scale of meteorological phenomena that range in size from several kilometers to around 100 kilometers
karst scenery	An uneven fissured landscape formed by underground drainage and caves.
isotopic dating	Dating technique used to determine the age of rock and mineral through the decay of radioactive elements.
jfo	Joint Field Office
chaff	Small strips of metal foil, usually dropped in large quantities from aircraft or balloons
b horizon	This layer is characterized by the following two features:
reclaimed water	domestic wastewater that is under the direct control of a treatment plant owner/operator which has been treated to a quality suitable for a beneficial use.
subsistence flows	the component of an instream flow regime that represents infrequent, naturally occurring low flow events that occur for a seasonal period of time
differential motion	Cloud motion that appears to differ relative to other nearby cloud elements, e.g
smpdbk	The Simplified Dam Break (DAMBRK) Model.
federal snow sampler	A snow sampler consisting of five or more sections of sampling tubes, one which has a steel cutter on the end
eddy cushion	The layer of slack or billowing water that pads the upstream face of rocks and other obstructions
tornado watch	Its issued when conditions are favorable for the development of tornadoes.
aeration	the mixing or turbulent exposure of water to air and oxygen to dissipate volatile contaminants and other pollutants into the air.
travel time	The time required for a flood wave to travel from one location to a subsequent location downstream.
300/500mb height	Upper air patterns are analysed and forecast at these heights. Wind and height fields at these heights, around 30000ft and 20000ft respectively, are used to establish weather patterns at the surface
carbohydrate	Is an organic compound composed of carbon, oxygen, and hydrogen atoms
dmtf	Debris Management Task Force
radar reflectivity	The sum of all backscattering cross-sections (e.g., precipitation particles) in a pulse resolution volume divided by that volume
nondegradation	an environmental policy that does not allow any lowering of naturally occurring water quality regardless of pre-established health standards.
heat	Heat is defined as energy in the process of being transferred from one object to another because of the temperature difference between them
plate tectonics	A theory that the Earth's surface is made up of large plates that are continuously moving and that interactions among the plates at their borders cause most major geologic activity
milligrams per liter	a unit of the concentration of a constituent in water or wastewater
liquefaction	(pronounced li-quh-FAC-shun) the transformation of water-saturated soil into a liquidlike mass, usually by the action of seismic waves.
element	A molecule composed of one type of atom
wind ripples	Wind ripples are miniature sand dunes between 5 centimeters and 2 meters in length and 0.1 to 5 centimeters in height
community	Refers to all the populations of interacting species found in a specific area or region at a certain time.
nitrogen	a plant nutrient that can cause an overabundance of bacteria and algae when high amounts are present, leading to a depletion of oxygen and fish kills
moveable bed streams	These are most common in the arid West, where steep slopes and lack of vegetation result in a lot of erosion
hvy	Heavy
ocean	embracing and integrating all knowledge pertaining to the ocean's physical boundaries, the chemistry and physics of sea water, and marine biology.
ground receive sites	A satellite dish and associated computer which receives signals from the GOES satellite, decodes the information, and transmits it to a another site for further processing
upper mantle	Layer of the Earth's interior extending from the base of the crust to 670 kilometers below the surface
rope thwarts	In paddle rafts, taut ropes or straps running crossways from tube to tube and often positioned just forward of cross tubes
coalescence	the process by which an ice crystal grows larger
ground water hydrology	The branch of hydrology that specializes in ground water; its occurrence and movements; its replenishment and depletion; the properties of rocks that control ground water movement and storage; and the methods of investigation and utilization of ground water.
solar wind	Mass of ionized gas emitted to space by the Sun
ambient background concentration	a representative concentration of the water quality in a receiving water body, determined from monitoring
delta	An alluvial deposit, often in the shape of the Greek letter "delta", which is formed where a stream drops its debris load on entering a body of quieter water.
channel routing	The process of determining progressively timing and shape of the flood wave at successive points along a river.
zoned embankment dam	An embankment dam which is comprised of zones of selected materials having different degrees of porosity, permeability and density.
stream segment	refers to the surface waters of an approved planning area exhibiting common biological, chemical, hydrological, natural, and physical characteristics and processes
hrs	hours
thermistor	A resistor whose resistance changes with temperature
bajada	Consecutive series of alluvial fans forming along the edge of a linear mountain range
saturation	Atmospheric condition where water is changing its phase to liquid or solid
pup	Principle User Processor
eta	"Eta" (from Greek) model generated every 12 hours by NCEP
cubic feet per second	A unit expressing rates of discharge
mass balance	The relative balance between the input and output of material within a system.
gaia hypothesis	The Gaia hypothesis states that the temperature and composition of the Earth's surface are actively controlled by life on the planet
nocturnal	Related to nighttime, or occurring at night.
bod	Biochemical Oxygen Demand
length of day	The time of Actual Sunset minus the time of Actual Sunrise
richter scale	the system invented by Dr
landslide	Term used to describe the downslope movement of soil, rock, and other weathered materials because of gravity.
fracture	Any break or rupture formed in an ice cover or floe due to deformation.
liana	Species of plant that uses the support of wood plants to elevate its leaves above the forest canopy.
trajectory	The curve that a body, such as a celestial object, describes in space
equilibrium drawdown	The ultimate, constant drawdown for a steady rate of pumped discharge.
granite	Medium to coarse grained igneous rock that is rich in quartz and potassium feldspar
hung up	Said of a raft that is caught on but not wrapped around a rock or other obstacle.
helm	The steering station of a yacht; the tiller or wheel by which the rudder is controlled.
work	The distance traveled by an object multiplied by the force applied to it in that direction.
pressure	The force per unit area exerted by the weight of the atmosphere above a point on or above the earth’s surface
convergence	A contraction of a vector field, usually said of winds; the opposite of divergence
tuberculation	development or formation of small mounds of corrosion products on the inside of iron pipe
dendrite	a starry-shaped snowflake that has accumulated moisture and developed feathery branches on its arms
equilibrium surface discharge	The steady rate of surface discharge which results from a long-continued, steady rate of net rainfall, with discharge rate equal to net rainfall rate.
divergent evolution	Creation of two or more unique species from one ancestral species through the differential evolution of isolated populations.
planitia	An IAU geographical feature name meaning “low plain.”
gradient	The steepness of a slope as measured in degrees, percentage, or as a distance ratio (rise/run).
coalescence	Process where two or more falling raindrops join together into a single larger drop because of a midair collision.
mean	A value computed by dividing the sum of a set of terms by the number of terms.
freezing rain	Rain that falls as liquid and freezes upon impact to form a coating of glaze on the colder ground or other exposed surfaces
kelvin	Gas Laws
evacuation time	The lead time that a populated coastal area must have to safely relocate all residents of vulnerable areas from an approaching hurricane
scree	An accumulation of weathered rock fragments at the base of a steep rock slope or cliff.
ecosystem	An ecosystem is a system where populations of species group together into communities and interact with each other and the abiotic environment.
cod	Chemical Oxygen Demand. A measure of the oxygen equivalent of the organic matter content of a sample that is susceptible to oxidation by a strong chemical oxidation. Differs from the BOD test in that COD uses oxygen derived from chemicals, while BOD uses oxygen derived from air dissolved in water.
paleoclimate	Climatic conditions in the geological past reconstructed from a direct or indirect data source.
synoptic track	Weather reconnaissance mission flown to provide vital meteorological information in data sparse ocean areas as a supplement to existing surface, radar, and satellite data
doppler effect	A shift in the frequency of an electromagnetic or sound wave due to the relative movement of the source or the observer.
silicate	Group of minerals that have crystal structures based on a silica tetrahedron (SiO4).
virga	Precipitation falling from the base of a cloud and evaporating before it reaches the ground.
hydraulic grade line	A line whose plotted ordinate position represents the sum of pressure head plus elevation head for the various positions along a given fluid flow path, such as along a pipeline or a ground water streamline
extinction	Disappearance of a species from all or part of their geographic range
steam eruption	a violent eruption that occurs when water comes in contact with magma, rapidly turns to steam, and causes the mixture to explode.
sunspots	Relatively cooler areas on the sun's surfaces
adfreezing	The process by which one object becomes adhered to another by the binding action of ice.
nephelometric turbidity unit	unit of measure for the turbidity of water
six-man raft	A boat 5% by 12 feet that will accommodate one to three people.The cheaper varieties, if used at all,should be fitted with frame and 5-foot oars and should carry only one person.
radiometer	An instrument that measures radiation power.
secondary wastewater treatment	treatment (following primary wastewater treatment) involving the biological process of reducing suspended, colloidal, and dissolved organic matter in effluent from primary treatment systems and which generally removes 80 to 95 percent of the Biochemical Oxygen Demand (BOD) and suspended matter
base width	The time duration of a unit hydrograph.
newton	A unit of force that creates an acceleration on a mass of 1 kilogram equal to 1 meter per second with no friction and under the conditions of a vacuum.
black blizzard	a popular term for a dust storm
flux	the rate at which a substance flows
nonsymbiotic mutualism	Mutualistic interaction where the mutualists live independent lives yet cannot survive without each other
corn snow ice	Rotten granular ice.
virga	Streaks or wisps of precipitation falling from a cloud but evaporating before reaching the ground.
vorticity	This is basically a measure of how much a column of air is spinning. Depending on direction of spin and speed of spin, a variety of surface conditions can be surmised, such as the development of low or high pressure at the surface.
milligram	One-thousandth of a gram.
forward velocity	The speed at which a hurricane moves along its path
forminifera	Microscopic organisms of the group protozoa that are found living mainly in marine environments
sedimentation	a large scale water treatment process where heavy solids settle out to the bottom of the treatment tank after flocculation.
r&r	Resource and Recovery
gravity dam	A concrete structure proportioned so that its own weight provides the major resistance to the forces exerted on it.
minor flooding	A general term indicating minimal or no property damage but possibly some public inconvenience.
funnel cloud	A rotating funnel extending from the base of a severe thunerstorm, associated with a rotating column of air that is NOT in contact with the ground at the moment. When the column is in contact with the ground and the cloud, then it is a tornado. Until that moment, the terms funnel cloud and tornado are NOT interchangeable.
rris	Rapid Response Information System
flat-plate collector	a solar power collector that absorbs the Sun's energy on a flat surface without concentrating or refocusing it.
profile	A graph showing variation of elevation with distance along a traverse.
mantle	Layer of the Earth's interior composed of mostly solid rock that extends from the base of crust to a depth of about 2,900 kilometers.
percolation deep	In irrigation or farming practice, the amount of water that passes below the root zone of the crop or vegetation.
hyphae	Thread like structures found on a fungus.
ground water outflow	That part of the discharge from a drainage basin that occurs through the ground water
green flash	A brilliant green coloration of the upper edge of the sun, occasionally seen as the sun's apparent disk is about to set below a clear horizon.
sensor	A device that detects a physical quantity.
ground water divide	A line on a water table where on either side of which the water table slopes downward
tailings pond	An excavated or diked area that is intended to contain liquid and solid wastes from mining and milling operations.
firestorm	huge fires caused by enormous numbers of separate fires all burning together
dynamic equilibrium	A dynamic equilibrium occurs when a system displays unrepeated average states through time.
watt	A metric unit of measurement of the intensity of radiation in Watts over a square meter surface (W/m2 or W m-2).
axis	An imaginary line through the middle of something.
savanna	A tropical or sub-tropical plant community characterized by trees and shrubs scattered among a cover of grasses, herbs and forbs
lomr-f	Letter of Map Revision Based on Fill
parametric data	Data such as rating curves, unit hydrographs, and rainfall/runoff curves which define hydrologic variables in models.
pancaking	In a threesome raft, when the howboat flips back onto the middle boat.
heavy freezing spray watch	A watch for an increased risk of a heavy freezing spray event to meet Heavy Freezing Spray Warning criteria but its occurrence, location, and/or timing is still uncertain.
gps	Global Positioning System
épaisseur de neige	L'épaisseur de neige est l'épaisseur de la neige accumulée sur le sol, mesurée en plusieurs points jugés représentatifs du voisinage immédiat, puis moyennée.
flood plain information studies	Reports usually prepared by the U.S
chaparral	A type of plant community common to areas of the world that have a Mediterranean climate (for example, California and Italy)
syncline	A downward fold in the crustal rocks, See anticline.
discharge curve	A curve that expresses the relation between the discharge of a stream or open conduit at a given location and the stage or elevation of the liquid surface at or near that location
interceptor sewer	very large sewer lines that collect the flow from main and trunk lines and carry them to treatment plants.
inversion	A layer in the atmosphere where the temperature increases with height.
refraction	the bending of electromagnetic radiation by its passage through a medium of a high refractive index
dust devil	A strong and long-lived whirlwind that ranges from a half of a meter wide and a few meters tall to more than 10 meters wide and more than 1,000 meters tall
north pole	Surface location defined by the intersection of the polar axis with Earth's surface in the Northern Hemisphere
sinkhole	a depression in the Earth's surface caused by dissolving of underlying limestone, salt, or gypsum
alkaline	sometimes water or soils contain an amount of alkali (strongly basic) substances sufficient to raise the pH value above 7.0 and be harmful to the growth of crops.
diorite	A coarse grained igneous rock of intrusive origin that is darker and chemically more mafic than granite.
parasitism	Biological interaction between species where a parasite species feeds on a host species.
electromagnetic spectrum	See spectrum.
subduction zones	areas where the crustal layer descends into the mantle
conglomerate	Coarse grained sedimentary rock composed of rounded rock fragments cemented in a mixture of clay and silt.
drip irrigation	a common irrigation method where pipes or tubes filled with water slowly drip onto crops
inversion	an increase in temperature with height, a reverse of the normal cooling with height
electron	A sub-particle of an atom that contains a negative atomic charge.
breakaway zone	the area where an avalanche is most likely to start or break away
mammal	Group of warm blooded vertebrate animals
matter	Is the material (atoms and molecules) that constructs things on the Earth and in the Universe.
food chain	Movement of energy through the trophic levels of organisms
fault	a crack in a layer of rock, usually caused by an earthquake or other movement in a rock layer; great splits between masses of rock at the earth's surface
perigee	The point nearest the earth on the moon's orbit
nautical mile	FEEDER BANDS
cell	A cell is the smallest self-functioning unit found in living organisms
climograph	Two dimensional graph that plots a location's air temperature and precipitation on times scales that range from a 24 hour period to a year.
return flow	(1) That part of a diverted flow that is not consumptively used and returned to its original source or another body of water
glacier	A slow moving mass of ice that is replenished at its source.
drainage basin	A part of the surface of the earth that is occupied by a drainage system, which consists of a surface stream or a body of impounded surface water together with all tributary surface streams and bodies of impounded surface water.
tongue	The smooth "v" of fast water found at the head of rapids.
fire line	a strip of ground, cleared of all combustible material, that is dug by firefighters to stop the advance of a wildfire (also called control line).
tube settler	device using bundles of tubes to let solids in water settle to the bottom for removal by conventional sludge collection means
divergence	The expansion or spreading out of a vector field; usually said of horizontal winds
buttress dam	Buttress dams are comprised of reinforced masonry or stonework built against concrete
rwa	Reimbursable Work Authorization
newton's laws of motion	Three fundamental postulates describing the basis of the mechanics of rigid bodies
neutral solution	Any water solution that is neutral (pH approximately 7) or has an equal quantity of hydrogen ions (H+) than hydroxide ions (OH-)
atmosphere	A thin envelope of gasses (also containing suspended solid and liquid particles and clouds) that encircles the globe.
convection	Atmospheric motions in the vertical direction resulting from surface heating and the subsequent rising of warm air
steady state equilibrium	In this type of equilibrium the average condition of the system remains unchanged over time.
heat	A form of energy transferred between systems because of the temperature differences between them.
radiation	in the context of the RReDC, synonymous with electromagnetic radiation, or the energy produced by an oscillating electrical (and magnetic) field, transmitted by photons
international date line	A line drawn almost parallel to the 180 degree longitude meridian that marks the location where each day officially begins
millibar	A unit of atmospheric pressure
optical depth	(technically known as the relative aerosol optical depth) usually considered to be synonymous with the airmass, is the approximate number of aerosols in a path through the atmosphere relative to the standard number of aerosols in a vertical path through a clean, dry atmosphere at sea level.
toxic hot spot	location in enclosed bay, estuary, or any adjacent waters that has toxic pollution problems in the water or sediment in excess of applicable standards.
leaching	Process in which water removes and transports soil humus and inorganic nutrients in solution.
cumulus	A cloud in the form of individual, detached domes or towers that are usually dense and well defined.
conduction	The transfer of energy (electrical, heat) within and through a conductor by means of internal particle or molecular activity.
trend	gives very accurate meteorological information at a specific airport and is indispensable for landing of aircraft within the next 2 hours
artesian basin	A source of fresh water formed where an aquifer is trapped between two layers of impervious rock.
subduction zone	a region where two plates come together and the edge of one plate slides beneath the other.
cellulose	A type of carbohydrate
prevailing	Most frequent.
syncline	A fold in rock layers that forms a trough-like bend.
zulu	Equivalent to UTC or Greenwich Mean Time (GMT).
minimum	The least value attained by a function, for example, temperature, pressure, or wind speed
snow pillow	An instrument used to measure snow water equivalents
atoll	Island surrounded by a coral reef.
suspended-sediment concentration	the ratio of the mass of dry sediment in a water-sediment mixture to the mass of the water-sediment mixture
cloud	A visible collection of minute particle matter, such as water droplets and/or ice crystals, in the air
biotic potential	Maximum rate that a population of a given species can increase in size (number of individuals) when there are no limits on growth rate.
acidic	the condition of water or soil that contains a sufficient amount of acid substances to lower the pH below 7.0.
sinkhole	A limestone hole into which a stream disappears.
temperature	The measurement of how hot or cold something is.
peridotite	Coarse grained ultramafic igneous rock composed mainly of olivine and pyroxene
system	A system is a set of interrelated components working together towards some kind of process.
solar system	The collection of celestial bodies that orbit around the Sun.
polypedon	An identifiable soil with distinct characteristics found in a location or region
lake-effect snow watch	Very Heavy lake-effect snowfall amounts of generally 6 inches (15 cm) in 12 hours or less or 8 inches (20 cm) in 24 hours or less are possible generally within 48 hours
toxicity reduction evaluation	a study conducted to determine the source(s) of toxicity in a discharge effluent so that these sources can be controlled sufficiently to allow a discharger to comply with their permit limits.
pyramid of biomass	Graphic model describing the distribution of biomass in an ecosystem or community at the trophic level
pump station	mechanical device installed in sewer or water system or other liquidcarrying pipelines to move the liquids to a higher level.
space exploration satellite	Technically a space probe because it is sent deep into space and does not necessarily orbit anything
fermentation	Decomposition and breakdown of organic matter by anaerobic means.
heat	A form of energy transferred between two systems by virtue of a difference in temperature
tidal cycle	The periodic changes in the intensity of tides caused primarily by the varying relations between the earth, moon, and sun.
ncp	National Oil and Hazardous Substances Pollution Contingency Plan
wastewater	water containing waste including greywater, blackwater or water contaminated by waste contact, including process-generated and contaminated rainfall runoff.
centripetal force	Force required to keep an object moving in a circular pattern around a center of rotation
geographical coordinate system	System that uses the measures of latitude and longitude to locate points on the spherical surface of the Earth.
gravity	Is the process where any body of mass found in the universe attracts other bodies with a force proportional to the product of their masses and inversely proportional to the distance that separates them
coral bleaching	Situation where coral lose their colorful symbiotic algae
distributional limit	Spatial boundary that defines the edge of a species geographical range.
power	The rate of change of energy over time, often expressed in watts.
dbz	The colors shown on the weather radar images represent the different echo intensities (reflectivity) measured in dBZ (decibels of Z) during each elevation scan
hydrostatic head	A measure of pressure at a given point in a liquid in terms of the vertical height of a column of the same liquid which would produce the same pressure.
hague line	The North Atlantic boundary between the U.S
grass	Type of plant that has long slender leaves that extend from a short stem or the soil surface.
lake	an inland body of water, usually fresh water, formed by glaciers, river drainage etc
range	A statistical measure of the dispersion of observation values in a data set
mitigation	The effort to reduce loss of life and property by lessening the impact of disasters
methane	Methane is very strong greenhouse gas found in the atmosphere
neap tide	Tide that occurs every 14 to 15 days and coincides with the first and last quarter of the moon
carbamates	a class of new-age pesticides that attack the nervous system of organisms.
interbasin transfer	the physical transfer of water from one watershed to another; regulated by the Texas Water Code.
sensible heat flux	Process where excess heat energy is transferred into the atmosphere
bearing	A system that measures in reference to the cardinal points of a compass in 90 degree quadrants.
hummock	In hydrologic terms, a hillock of broken ice which has been forced upward by pressure
backdraft	inside buildings, when the oxygen in a room is almost used up, the fire begins to die down from lack of the substance; the flames lower and the room fills with smoke; but if you open the door to the room at that time, the fire sucks oxygen in so hard that fire gases explode
inversion	An increase in temperature with height
chlorofluorocarbons	An anthropogenic compound invented by chemists in 1928 considered to be a major contributor to the development of the stratospheric Ozone hole.
ofm	FEMA’s Office of Financial Management
centripetal force	An inward-directed force that confines an object to a curved path; the result of other forces.
mineralization	Decomposition of organic matter into its inorganic elemental components.
entisols	Soil order (type) of the United States Natural Resources Conservation Service Soil Classification System
mixed liquor	a mixture of activated sludge and water containing organic matter undergoing treatment in an aeration tank.
photochemical smog	Photochemical smog is a condition that develops when primary pollutants (oxides of nitrogen and volatile organic compounds created from fossil fuel combustion) interact under the influence of sunlight to produce a mixture of hundreds of different and hazardous chemicals known as secondary pollutants
magnitude	the size of an earthquake as measured on the Richter scale
ulysses	A NASA space probe that is studying the sun
windward	Upwind side or side directly influenced to the direction that the wind blows from
lagoon	a shallow pond where sunlight, bacterial action, and oxygen work to purify wastewater
ecoregion	a geographic area over which the macroclimate is sufficiently uniform to permit development of similar ecosystems on sites with similar geophysical properties.
stoplogs	Large logs, timbers or steel beams placed on top of each other with their ends held in guides on each side of a channel or conduit providing a temporary closure versus a permanent bulkhead gate.
mesocyclone	and indicates favorable conditions for tornado development.
overhang	Radar term indicating a region of high reflectivity at middle and upper levels above an area of weak reflectivity at low levels
trend	A tendency over a period of time.
radioactive decay	Natural decay of the nucleus of an atom where alpha or beta particle and/or gamma rays are released at a fixed rate.
phylum	A group or category used in the taxonomic and/or phylogenic classification of organisms
fire warning	A fire is currently burning in the area and evacuation is recommended.
heliostat	a large flat mirror, usually on a tracker so that it can continuously reflect the sun's rays onto a central receiver
clay	Mineral particle with a size less than 0.004 millimeters in diameter
smog	Generic term used to describe mixtures of pollutants in the atmosphere
terrestrial	Of or relating to the Earth.
uniformitarianism	Is a theory that rejects the idea that catastrophic forces were responsible for the current conditions on the Earth
detergent	synthetic washing agent that helps remove dirt and oil
solar eclipse	An eclipse of the sun occurs when the moon is in a direct line between the sun and the earth, casting some of the earth's surface in its shadow
bulkhead	A structure or partition built to retain or prevent sliding of the land.
navier-stokes equations	a set of equations that describe the physics governing the motion of a fluid
mercury barometer	Type of barometer that measures changes in atmospheric pressure by the height of a column of mercury in a U-shaped tube which has one end sealed and the other end immersed in an open container of mercury
hoar frost	Deposits of ice having a crystalline appearance, generally assuming the forms of scales, needles, feathers or fans
south pole	Surface location defined by the intersection of the polar axis with Earth's surface in the Southern Hemisphere
graphical model	A compilation or display of data in a form (e.g., a map) that can be readily useful.
subduction zone	An area where two plates come together and one slides under another
feedback loop	Process where the output of a system causes positive or negative changes to some measured component of the system.
irrigation	the controlled application of water for agricultural purposes through manmade systems to supply water requirements not satisfied by rainfall
improved property	A structure, facility or item of equipment that was built, constructed or manufactured
hz	1) Haze- An aggregation in the atmosphere of very fine, widely dispersed, solid or liquid particles, or both, giving the air an opalescent appearance that subdues colors
facilitation model of succession	This model of succession suggests that the change in plant species dominance over time is caused by modifications in the abiotic environment that are imposed by the developing community
hydraulic grade line	In hydrologic terms, a line whose plotted ordinate position represents the sum of pressure head plus elevation head for the various positions along a given fluid flow path, such as along a pipeline or a ground water streamline.
inferno	a huge, roaring fire
operable unit	a term used by the Superfund program to describe a discrete action that comprises an incremental step toward comprehensively addressing site problems
storm sewer	a sewer that carries only surface runoff, street wash, and snow melt from the land
drainage area	An area having a common outlet for its surface runoff (also see Watershed and Catchment Area).
carbonate	Compound consisting of a single atom of carbon and three atoms of oxygen
inversely proportional	Cause and effect relationship between two variables where a positive or negative change in the quantity of one causes a predictable opposite change in quantity in the other.
dew	Small droplets of water found on surfaces, formed when temperatures on these surfaces reaches the dew point.
thermal gradient	temperature difference between two areas.
reclaimed wastewater	treated wastewater that can be used for beneficial purposes, such as irrigating certain plants.
pontoon	An inflatable boat 22 feet long or larger
density of snow	The ratio, expressed as a percentage, of the volume which a given quantity of snow would occupy if it were reduced to water, to the volume of the snow
velocity	The speed of movement of an object in one direction.
back pivot	Turning the raft from a ferry angle to a stem-downstream position
solute	a substance that is dissolved in another substance, thus forming a solution.
discharge permit	a permit issued by a state or the federal government to discharge effluent into waters of the state or the United States
rayleigh scattering	Caused by spherical particles whose diameter is much smaller than the wavelength of scattered radiation; responsible for the blue of the daytime sky.
cartography	Field of knowledge that studies map construction
threatened species	Under the Federal Endangered Species Act, animal populations may be determined to be either threatened or endangered
frost	Crystals of frozen vapor.
virus	Is a fragment of DNA or RNA that depends on the infection of host cells for their reproduction
prescribed burn	a planned, controlled fire that clears flammable debris from the forest floor.
oxisol	Soil order (type) of the United States Natural Resources Conservation Service Soil Classification System
probability	Statistical chance that an event will occur.
tropical disturbance	A discrete system of apparently organized convection originating in the tropics or subtropics, having a non-frontal migratory character and maintaining its identity for 24 hours or more.
above	Upriver from.
winch	A device used to give a mechanical advantage when hauling on the lines.
westerlies	West African Disturbance Line (WADL): It is a line of convection about 300 miles long, similar to a squall line
dependent variable	Variable in a statistical test whose observation's values are thought to be controlled through cause and effect by another independent variable modeled in the test.
precipitate	a solid which has come out of an aqueous solution
ecotone	a transition zone between two distinctly different ecosystems or communities.
kinetic energy	The energy an object posses because of its motion.
smma	Standard Mitigation Measures Agreement
ground ice	General term used to describe all bodies of ice in the ground surface of the permafrost layer
tropopause	The place that marks the end of the troposphere and the start of the stratosphere marked by a change in temperature.
ore	A mineral from which metals can be extracted.
isotherm	A line connecting points of equal temperature.
onshore-offshore transport	The up and down movement of sediment roughly perpendicular to a shoreline because of wave action.
radial velocity	Component of motion toward or away from a given location
fima	Federal Insurance and Mitigation Administration
net primary productivity	Total amount of chemical energy fixed by the processes of photosynthesis minus the chemical energy lost through respiration.
squall line	A non-frontal band, or line, of thunderstorms.
pyroclastic flow	a rapid flow of hot material consisting of ash, pumice, other rock fragments, and gas ejected by an explosive eruption.
producer	An organism that can synthesize the organic nutrients in requires for growth through processes like photosynthesis.
perfected water right	a water right which indicates that the uses anticipated by an applicant, and made under permit, were made for beneficial use
consumptive use	the quantity of water not available for reuse
publicly-owned treatment works	a wastewater treatment plant that is owned by a state, unit of local government or Indian tribe, usually designed to treat domestic wastewaters
duration of ice cover	The time from freeze-up to break-up of an ice cover.
freeze	It occurs when the temperature falls below 32 degrees over a large area for an extended period of time.
paleosol	A soil exhibiting features that are the result of some past conditions and processes.
location	A term used in geography that deals with the relative and absolution spatial position of natural and human-made phenomena.
starch	Complex carbohydrate composed of thousands of glucose units
natural ionizing radiation	Ionizing radiation that comes from natural sources in the environment.
convection	The transfer of heat or moisture in a medium by the movement of a mass or substance
tree	A large woody plant that has a trunk which supports branches and leaves.
watershed	Land area from which water drains toward a common watercourse in a natural basin.
freezup jam	Ice jam formed as frazil ice accumulates and thickens.
oceanography	it is equivalent to specific gravity and represents the ratio of the weight of a given volume of sea water to that of an equal volume of distilled water at 4.0°C or 39.2°F.
solar altitude	The angle of the sun 90 degrees or less above the horizon.
emissivity	The ratio of total radiative output from a body per unit time per unit area at a specific temperature and wavelength to that of a black body under the same environmental conditions.
niche specialization	Process where evolution, through natural selection, adapts a species to a particular set of abiotic and biotic characteristics within a habitat.
conduction	The transfer of energy from one object to another due to the random motions of molecules
facilitation	Modification of a system that makes subsequent modifications easier.
unit hydrograph	The discharge hydrograph from one inch of surface runoff distributed uniformly over the entire basin for a given time period.
threatened species	Species that is still plentiful in its natural range but is likely to become endangered because of declining population numbers.
exploitation	Form of competition where the indirect effects of the two or more species or individuals reduce the supply of the limiting resource or resources needed for survival.
geographic cycle	Theory developed by William Morris Davis that models the formation of river-eroded landscapes
fire weather advisory	A fire weather advisory is issued when dry conditions in the advisory area result in a situation where forest or brush fires are possible.
forest	A predominately wooded area of land.
carbon dioxide	A critical atmospheric gas necessary for photosynthesis
base flow	Rate of discharge in a stream where only the throughflow and groundwater flow from subsurface aquifers contribute to the overall flow.
paleontologist	a scientist who studies fossils to determine facts about prehistoric plants and creatures
latent heat of vaporization	Heat required to change the phase of water from liquid to vapor; 540 to 600 calories per gram, depending on the temperature of the water.
bromeliad	Plants of the bromeliad family (Bromeliaceae)
host	Organism that develops disease from a pathogen or is being feed on by a parasite.
freezing rain	A type of precipitation
grazing food chain	Model describing the trophic flow of organic energy in a community or ecosystem.
divide	The high ground that forms the boundary of a watershed
sea-floor spreading	The process of oceanic crust creation and sea-floor movement that occurs at the mid-oceanic ridge.
deposition	Process by which water changes phase directly from a vapor into a solid without first becoming a liquid.
sewage treatment plant	a facility designed to receive the wastewater from domestic sources and to remove materials that damage water quality and threaten public health and safety when discharged into receiving streams or bodies of water
stationary front	A front which is nearly stationary or moves very little since the last synoptic position
rod	A graduated staff used in determining the difference in elevation between two points
electromagnetic radiation	Energy transfer in the form of waves that have both electrical and magnetic properties; occurs even in a vacuum.
tropical disturbance	An organized group of thunderstorms often found over a tropical ocean that generates a slight cyclonic flow of less than 37 kilometers per hour
finite element	a method of solving the governing equations of a numerical model by dividing the spatial domain into elements in each of which the solution of the governing equations is approximated by a continuous function.
evaporimeter	An instrument which measures the evaporation rate of water into the atmosphere.
asap	AHOS SHEF Automatic Processing System
organic soil	Soil order (type) of the Canadian System of Soil Classification
site-specific	Term used in conjunction with "forecast" or "warning" to convey the fact that a hydrologic (stream) forecast is produced for an individual stream gage location as opposed to a general area (e.g., a city, zone, or county) as is commonly done in many types of weather forecasts.
stepped leader	A faint, negatively charged channel that emerges from the base of a thunderstorm and propagates toward the ground in a series of steps of about 1 microsecond duration and 50-100 meters in length, initiating a lightning stroke.
fujiwhara effect	A binary interaction where tropical cyclones within a certain distance (300-750 nautical miles depending on the sizes of the cyclones) of each other begin to rotate about a common midpoint
rainsplash	Soil erosion caused from the impact of raindrops.
seepage	percolation of water through the soil from unlined canals, ditches, laterals, watercourses, or water storage facilities.
luvisol soil	Soil order (type) of the Canadian System of Soil Classification
recurrence interval	average amount of time between events of a given magnitude
classification	Process of grouping things into categories.
karst	Landform type with limestone bedrock and dominated by geomorphic features created from solution chemical weathering.
broken-line graph	A graph in which points representing values are connected by a broken line.
shear	Since both parameters are important for severe weather development, higher values generally indicate a greater potential for severe weather
homologous flares	In solar-terrestrial terms, solar flares that occur repetitively in the same active region, with essentially the same position and with a common pattern of development
hic	Hydrologist In Charge
proportional	Cause and effect relationship between two variables where a positive or negative change in the quantity of one causes a predictable similar quantity change in the other.
zenith	The point which is elevated 90 degrees from all points on a given observer's astronomical horizon
subduction zone	Linear area where tectonic subduction takes place.
eutrophication	Physical, chemical and biological changes in a water body as a result of the input nitrogen and phosphorus.
breccia	Coarse grained sedimentary rock composed of cemented angular rock fragments.
asaptran	The software component of ASAP.
albedo	The ratio of the amount of electromagnetic radiation reflected by a body to the amount incipient upon it, commonly expressed as a percentage
vortex	a rapidly whirling spiral
coriolis force	A deflective force arising from the rotation of the Earth on its axis; affects principally synoptic-scale and planetary-scale winds
sewerage	the entire system of sewage collection, treatment, and disposal.
prp	Preferred Risk Policy
brine	highly salty and heavily mineralized water containing heavy metal and organic contaminants.
ionosphere	A complex atmospheric zone of ionized gases that extends between 50 and 400 miles (80 to 640 kilometers) above the earth's surface
heavy freezing spray	An accumulation of freezing water droplets on a vessel at a rate of 2 cm per hour or greater caused by some appropriate combination of cold water, wind, cold air temperature, and vessel movement.
sedimentation tanks	wastewater tanks in which floating wastes are skimmed off and settled solids are removed for disposal.
shorty pontoon	A 22- to 25-foot pontoon
drought index	Computed value which is related to some of the cumulative effects of a prolonged and abnormal moisture deficiency
grassed waterway	natural or constructed watercourse or outlet that is shaped or graded and planted in suitable vegetation for the disposal of runoff water without erosion.
needle ice	A form of periglacial ground ice that consists of groups ice slivers at or immediately below the ground surface
fecal coliform	the portion of the coliform bacteria group which is present in the intestinal tracts and feces of warm-blooded animals
evolution	Is a process by which species come to possess genetic adaptations to their environment
house boulder	A house-sized boulder.
www	World Wide Web
thole pin	An upright steel pin on a rowing frame that serves as a fulcrum, or pivot point, for the oar
protoplasm	Substances making up a cell including its exterior membrane.
urban flooding	Flooding of streets, underpasses, low lying areas, or storm drains
hic	Hydrologist in Charge of an RFC.
chemical energy	Energy consumed or produced in chemical reactions.
regolith	Loose layer of rocky material overlying bedrock.
accretion	Growth of a cloud or precipitation particle by the collision and union of a frozen particle with a super-cooled water drop.
relationship	State of having something in common.
microns	also called a micrometer, a unit of length equal to one millionth of a meter.
conelet	a small cone on the side of a large volcano.
absorption	The process whereby a portion of the radiation incident on an object is converted to heat.
solar time	The time associated with the diurnal motion of the sun across the celestial sphere.
wave refraction	The re-orientation of a wave so that it approaches a shoreline at a more perpendicular angle
osmosis	the movement of water molecules through a thin membrane
nadir	The point on any given observer's celestial sphere diametrically opposite of one's zenith.
regeneration	the process of making or starting anew.
latitude	Les coordonnées de latitude pour les stations climatologiques sont généralement celles du parc des instruments; cependant, avant le 1 avril 1986, pour les stations principales (aéroports), on indiquait normalement l’emplacement officiel de ces aéroports
rockfall	Type of mass movement that involves the detachment and movement of a small block of rock from a cliff face to its base
transmissibility	the capacity of a rock to transmit water under pressure
wasteload allocation	term used in conjunction with the TMDL Program, a WLA is the portion of a receiving water's loading capacity that is allocated to one of its existing or future point sources of pollution
return flow	surface water that returns to the natural environment after diversion for beneficial uses, such as for irrigation.
firejumper	a specialized firefighter who parachutes to strategic locations from airplanes to battle wildfires.
pediplain	An arid landscape of little relief that is occasionally interrupted by the presence of scattered inselbergs
tropical disturbance	A discrete tropical weather system of apparently organized convection -- generally 100 to 300 n mi in diameter -- originating in the tropics or subtropics, having a nonfrontal migratory character, and maintaining its identity for 24 hours or more
gas	Phase
surface tension	Tension of a liquid's surface
composites	Plants of the compositae family (Asteraceae)
interference	Form of competition where an individual directly prevents the physical establishment of another individual in a portion of a habitat.
northing	Second measurement of a grid reference used to specific the location of a point on a rectangular coordinate system
precession	The wobble of the Earth's axis
glaciofluvial	Geomorphic feature whose origin is related to the processes associated with glacial meltwater.
relocated	A term used in an advisory to indicate that a vector drawn from the preceding advisory position to the latest known position is not necessarily a reasonable representation of the cyclone's movement.
eccentricity	Geometric shape of the Earth's orbit
tragedy of the commons	the idea that no one takes responsibility for things that everybody owns.
capillarity	(1)The degree to which a material or object containing minute openings or passages, when immersed in a liquid, will draw the surface of the liquid above the hydrostatic level
rowing frame	A rigid frame that provides a seatfor the oarsman and allows the raftto be controlled by large oars
ph	numeric value that describes the intensity of the acid or basic (alkaline) conditions of a solution
macroscale	Meteorological expression referring to synoptic events occurring on a scale of thousands of kilometers, such as warm and cold fronts.
calcium carbonate	Compound consisting of calcium and carbonate
excessive heat watch	Its issued when the following conditions occur within 12-36 hours: a heat index of at least 105 degrees for more than 3 hours per day for 2 consecutive days or a heat index more than 115 degrees for any period of time.
ring of fire	See Circum-Pacific Belt.
biodiversity	the variety of plant, animal, and microorganism species present in the ecosystem and the community structures the form.
conservation storage	Storage of water for later release for usual purposes such as municipal water supply, power, or irrigation in contrast with storage capacity used for flood control..
price current meter	A current meter with a series of conical cups fastened to a flat framework through which a pin extends
variable ceiling	Occurs when the height of a ceiling layer increases and decreases rapidly, The ascribed height is the average of all the varying values.
aurora australis	Southern hemisphere equivalent of the aurora borealis.
sill	Horizontal planes of igneous rock that run parallel to the grain of the original rock deposits.They form when magma enters and cools in bedding planes found within the crust
ecology	The study of the factors that influence the distribution and abundance of species.
hydrometeorologists	In hydrologic terms, individuals who have the combined knowledge in the fields of both meteorology and hydrology which enables them to study and solve hydrologic problems where meteorology is a factor.
entrainment	One of three distinct processes involved in erosion
seismographs	instruments that make an automatic record of the time, duration, direction, and intensity of earthquakes
law of reflection	The angle of incident reflection is to equal to the angle of reflected radiation.
evaporation	The process by which water changes phase from a liquid to a vapor at a temperature below the boiling point of water.
gross primary productivity	Total amount of chemical energy fixed by the processes of photosynthesis.
positive feedback	Change in the state of a system that enhances the measured effect of the initial alteration.
transmittance	the fraction or percent of a particular frequency or wavelength of electromagnetic radiation that passes through a substance without being absorbed or reflected.
section	A portion of river located between two points; a stretch.
sunspot	Dark colored region on the Sun that represents an area of cooler temperatures and extremely high magnetic fields.
centripetal force	The force required to keep an object moving in a curved or circular path
regional metamorphism	Large scale metamorphic modification of existing rock through the heat and pressure of plutons created at tectonic zones of subduction.
glacial retreat	The backwards movement of the snout of a glacier.
sublimation	The transition of a substance from the solid phase directly to the vapour phase, or vice versa, without passing through the liquid phase.
urbanization	Expansion of cities into rural regions because of population growth
dry flood proofing	A dry flood proofed building is sealed against floodwaters
tertiary consumer	Organisms that occupy the fourth trophic level in the grazing food chain
contents	The volume of water in a reservoir
ultisols	Soil order (type) of the United States Natural Resources Conservation Service Soil Classification System
rain foot	A horizontal bulging near the surface in a precipitation shaft, forming a foot-shaped prominence
rift	Zone between two diverging tectonic plates
gross secondary productivity	Total amount of chemical energy assimilated by consumer organisms.
diurnal	Pertaining to actions or events that occur during a twenty-four hour cycle or recurs every twenty-four hours
self-supplied water	water withdrawn from a surface- or ground-water source by a user rather than being obtained from a public supply
joule	A unit used to measure amounts of energy
colonization	Movement of individuals or propagules of a species to a new territory.
infiltration	Movement of water through the soil surface into the soil.
fault	crack in Earth's surface where two plates or sections of the crust push and slide in opposite directions against one another.
lower mantle	Layer of the Earth's interior extending from 670 to 2,900 kilometers below the surface crust
soil horizon	Layer within a soil profile that differs physically, biologically or chemically from layers above and/or below it.
daily flood peak	The maximum mean daily discharge occurring in a stream during a given flood event.
ozone shield	Ozone (O3) within the stratosphere that filters out potentially lethal intensities of ultraviolet radiation (UV) from the sun.
avalanche	a large mass of snow, ice, soil or rock, which detaches from a mountain slope and slides or falls suddenly downward; the sliding or falling of rocks, snow or other materials down the side of a mountain
competitive exclusion	Situation where no two competitively interacting species can occupy exactly the same fundamental niche indefinitely because of resource limitations
inverted relief	A landscape in which synclines form high ground and anticlines form valleys.
local action statement	A release prepared by a National Weather Service Forecast Office in or near a threatened area giving specific details for its area of responsibility
perihelion	The point of the earth's orbit that is nearest to the sun
emergency public information	Information disseminated primarily, but not unconditionally, at the time of an emergency frequently includes actions, instructions and direct orders.
isohyet	A line connecting points of equal precipitation amounts.
sked	A position report issue every 6 hours.
center	The vertical axis or core of a tropical cyclone
primary wastewater treatment	the first stage of the wastewater-treatment process where mechanical methods, such as filters and scrapers, are used to remove pollutants
dnr	Department of Natural Resources
mean	Statistical measure of central tendency in a set of data
inferential statistics	Statistical test that makes generalizations about a population based of the numeric information obtained from a sample based on the laws of probability.
point-focusing concentrator	a solar power generator which uses a series of tracking mirrors (heliostats), Fresnel lenses, or a paraboloid (3-dimensional parabola, or dish) of mirrors to focus solar energy onto a single central receiver such as a boiler, engine, or photovoltaic array.
foliation	Process where once randomly distributed platy minerals in a rock become reoriented, because of metamorphism, in a parallel manner.
rill	a small channel eroded into the soil by surface runoff; can be easily smoothed out or obliterated by normal tillage.
coriolis effect	A force per unit mass that arises solely from the earth's rotation, acting to deflect fluid parcels that are in motion
spectrometer	An instrument used to study the electromagnetic spectrum.
giardiasis	a disease that results from an infection by the protozoan parasite Giardia Intestinalis, caused by drinking water that is either not filtered or not chlorinated
ecosystem	a community of plants and animals, including humans, and their physical surroundings.
organism abundance and condition	that portion of an Index of Biotic Integrity that is a metric measuring species abundance and condition, including proportion of individuals as hybrids and proportion of individuals with disease, tumors, physical damage, or physical anomalies.
productivity	Rate of energy fixation or storage of biomass by plants
loam	A soil that contains a roughly equal mixture of clay, sand, and silt
bulkhead	A partition to strengthen the frame of a yacht.
surface temperature	The air temperature measured in the shade at 1.5 m (or 5 ft) above the ground.
finite volume	a method of solving the governing equations of a numerical model by dividing the spatial domain into a mesh of nodes and corresponding volumes around each node
visibility	the distance over which objects can be seen
orbit	A path described by one body in its revolution about another.
drainage divide	The boundary line, along a topographic ridge or along a subsurface formation, separating two adjacent drainage basins.
snow	snow pellets, snow grains, ice crystals, ice pellets, and hail.
microburst	A small, concentrated downburst affecting an area less than about 2.5 miles across. Most microbursts are rather short-lived (5 minutes or so), but on rare occasions have been known to last up to 30 minutes.
radiation	it is waves of energy propagated though space or through a material media.
dalton's law	States that the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of the gases
biodiversity	The diversity of different species (species diversity), genetic variability among individuals within each species (genetic diversity), and variety of ecosystems (ecosystem diversity)
temperature	The degree of hotness or coldness as measured on some definite temperature scale.
tharsis*	An elevated region on Mars containing the Tharsis Montes, four extremely large volcanos: Olympus, Ascraeus, Pavonis, and Arsia
strainer	Brush, fallen trees, bridge pilings, or anything else that allows the current to sweep through but pins boots and boaters
*microburst	A small, concentrated downburst affecting an area less than 4 kilometers (about 2.5 miles) across
anchor ice	Submerged Frazil ice attached or anchored to the river bottom, irrespective of its formation.
thalweg	In hydrologic terms, the line of maximum depth in a stream
conduction	Conduction consists of energy transfer directly from atom to atom and represents the flow of energy along a temperature gradient.
bolson	Is a closed desert basin with no drainage outlet, surrounded by mountains.
ice gorge	The gorge or opening left in a jam after it has broken.
ppm	See parts per million.
geocoding	The conversion of features found on an analog map into a computer-digital form
weather satellites	unmanned spaceships in orbit up to 22,000 miles above the earth; they have cameras that photograph the planet and send signals to receiving stations on earth
inverse square law	Intensity of radiation decreases as the inverse square of distance traveled.
impermeable layer	a layer of solid material, such as rock or clay, which does not allow water to pass through.
calorie	amount of energy required to raise the temperature of 1 gram of water 1 degree Celsius.
crown fire	a fire that spreads through the treetops, or crown, of a forest.
draw stroke	paddling technique of moving a boat sideways toward the paddle
gallery	a wooden, steel or concrete barrier or bridge built in known avalanche paths; a gallery allows cascading snow to pass over highways and railroad racks
ice-forming nuclei	Tiny particles that promote the formation of ice crystals at temperatures well below freezing; include freezing nuclei and deposition nuclei.
food chain	transfer of food energy from one organism to another
stream order	The relative position, or rank, of a stream channel segment in a drainage network.
fold	Wavelike layers in rock strata that are the result of compression.
gleization	A soil formation process that occurs in poorly drained environments
light year	Distance that light travels in the vacuum of space in one year
discontinuity	Comparatively large contrast in meteorological elements over a relatively small distance or period of time
circle of illumination	A line that bisects areas on the Earth receiving sunlight and those areas in darkness
grounded ice	Ice that has run aground or is contact with the ground underneath it.
oil	Hydrocarbon based liquid commonly found in the pores of sedimentary rocks of marine origin.
t rolls	[Slang], same as transverse rolls.
input	Addition of matter, energy, or information to a system
hole	A reversal
equation	A mathematical statement saying that two amounts or values are the same or equal.
mesosphere	The layer of the atmosphere located between the stratosphere and the ionosphere, where temperatures drop rapidly with increasing height
organic matter	Mass of matter that contains living organisms or non-living material derived from organisms
basin	A topographic rock structure whose shape is concave downwards.
epiphyte	Type of vegetation that gets its physical support from the branches of other plants
alps	Mountain system composed of more than fifteen principle mountain ranges that extends in an arc for almost 660 miles (1,060 kilometers) across south-central Europe.
gene frequency	Frequency of alleles at an individual or population level.
hazard mitigation	Any cost-effective measure that will reduce the potential for damage to a facility from a disaster event
sustained overdraft	Long-term withdrawal from the aquifer of more water than is being recharged.
sample	A sample is a subset group of data selected from a larger population group
rating curve	A graph showing the relationship between the stage, usually plotted vertically (Y-axis) and the discharge, usually plotted horizontally (X-axis).
noaa	National Oceanic and Atmospheric Service
pfor	Principal Federal Official Representative
antenna	A conductor or system of conductors for radiating and/or receiving radio energy
national response team	representatives of 13 federal agencies that, as a team, coordinate federal responses to nationally significant incidents of pollution and provide advice and technical assistance to the responding agencies.
gravitational force	The product of mass and gravitational acceleration.
secondary substance	Organic chemical produced by a plant that has no direct function in its metabolism
sheet	A line that controls sails and adjusts their angle of attack and their trailing edge.
inundation map	Delineates areas that would be flooded as a result of a dam failure
groundwater recharge	the inflow to a ground water reservoir.
magma	hot molten rock created by the partial melting of the crust and mantle at high temperatures far below the ground
feedbacks	A sequence of interactions where one change leads to some other change, which can act to either reinforce or inhibit the original change.
speed of light	Velocity of light in a vacuum
wavelength	The distance between one crest of a wave and another.
infiltration capacity	The maximum rate at which water can enter the soil at a particular point under a given set of conditions.
dry crack	Crack visible at the surface but not going right through the ice cover, and therefore it is dry.
fire vortex	During a natural or prescribed fire, the flames drastically heat the surface which allows for hot air near the surface to rise
sdm	Station Duty Manual
evacuation	the movement of people out of an area because of war or disaster
prediction	Forecast or extrapolation of the future state of a system from current or past states.
spectral model	A model in which the prognostic field variables are represented as sums of a finite set of spectral modes rather than at gridpoints
coniferous vegetation	Cone-bearing vegetation of middle and high latitudes that are mostly evergreen and that have needle-shaped or scale like leaves
tornado alley	An area stretching from Texas though Iowa, where many U.S
electric vehicles	vehicles that run on electric batteries and motors instead of gasoline-powered engines.
weighing-bucket rain gauge	A device that is calibrated so that the weight of cumulative rainfall is recorded directly in terms of millimeters or inches.
satellite	An object which has been sent into space in order to collect information or to be part of a communications system.
convection	Derechos include any family of downburst clusters produced by an extratropical MCS, and can produce damaging straight-line winds over areas hundreds of miles long and more than 100 miles across.
photon	the fundamental particle or quantum of electromagnetic radiation (radiant energy).
brunisol soil	Soil order (type) of the Canadian System of Soil Classification
trophic composition	that portion of an Index of Biotic Integrity that is a metric measuring the proportion of species and proportions of omnivores, insectivores, and omnivores.
artificial control	A weir or other man-made structure which serves as the control for a stream-gaging station.
ceilometer	An instrument that automatically records cloud height.
glacial surge	A rapid forward movement of the snout of a glacier.
snow stake	A 1-3/4 inch square, semi-permanent stake, marked in inch increments to measure snow depth.
braided stream	Characterized by successive division and rejoining of streamflow with accompanying islands
water quality standards	laws or regulations, promulgated under Section 303 of the Clean Water Act, that consist of the designated use or uses of a waterbody or a segment of a waterbody and the water quality criteria that are necessary to protect the use or uses of that particular waterbody
isopleth	A line connecting equal points of value
storm surge	An increase in water level associated with some significant meteorological event such as:
evaporation	Evaporation can be defined as the process by which liquid water is converted into a gaseous state
intensity	description of the physical damage caused by an earthquake.
pedogenic regime	The particular soil forming process that operates in a certain climate
hnd	Hundred
parasite	Consumer organism that feeds on a host for an extended period of time
kelvin temperature scale	A temperature scale in which 0 degrees is absolute zero, or the point at which all molecular motion ceases
bioremediation	a process that uses living organisms to remove pollutants.
fema	Federal Emergency Management Agency
eukaryote	Organisms whose cells have a membrane-bound nucleus and many specialized structures located within their cell boundary
directional shear	The component of wind shear which is due to a change in wind direction with height, e.g., southeasterly winds at the surface and southwesterly winds aloft
hyder flare	In solar-terrestrial terms, a filiment-associated two-ribbon flare, often occurring in spotless regions
influent seepage	Movement of gravity water in the zone of aeration from the ground surface toward the water table.
ground fire	a fire that burns beneath layer of dead plant material on the forest floor.
snow roller	The product of moist, cohesive snow that when initiated by wind rolls across the landscape, gathering snow until it can no longer move
fresh water inflow requirements	freshwater flows required to maintain the natural salinity, nutrient, and sediment delivery in a bay or estuary that supports their unique biological communities and ensures a healthy ecosystem.
moraine	A mass of boulder clay carried by a glacier.
bottomset bed	Horizontal deltaic deposit of alluvial sediment composed of fine silt and clay.
isthmus	Narrow strip of land linking two larger land masses.
oar frame	Same as rowing frame.
aerobic	life or processes that require, or are not destroyed by, the presence of oxygen.
establishment	Subsequent growth and/or reproduction of a colonized species in a new territory.
cercla	Comprehensive Environment Response, Compensation and Liability Act
dry adiabatic lapse rate	Rising unsaturated (clear) air parcels cool at the rate of about 10 Celsius degrees per 1000 m of uplift (or 5.5 Fahrenheit degrees per 1000 ft).
sleeper	Submerged rock or boulder just below the surface, usually marked by little or no surface disturbance.
spectrograph	An instrument that spreads out the light gathered by a telescope so that it can be analyzed to determine many different properties of celestial objects
system relationship	Is the association that exist between the elements and attributes of a system based on cause and effect.
grassland	Ecosystem whose dominant species are various types of grass
convergence	Divergence at upper levels of the atmosphere enhances upward motion, and hence the potential for thunderstorm development (if other factors also are favorable).
aquaculture	farming of plants and animals that live in water, such as fish, shellfish, and algae.
hybrid vehicles	vehicles that run on more than one source of power, such as gasoline and electricity.
voyager	Launched in 1977, NASA's twin Voyager space probes studied the outer planets before continuing on into deep space
floodproofing	The process of protecting a building from flood damage on site
cryosol soil	Soil order (type) of the Canadian System of Soil Classification
folding	The deformation of rock layers because of compressive forces to form folds.
combined sewer overflow	the discharge of a mixture of storm water and domestic waste when the flow capacity of a sewer system is exceeded during rainstorms.
chlorophyll	Green pigment found in plants and some bacteria used to capture the energy in light through photosynthesis.
leaf drip	The rain water that fall to the ground surface from plant leaves after it has been intercepted by these structures.
cation exchange	Chemical trading of cations between the soil minerals and organic matter with the soil solution and plant roots.
crack	A separation formed in an ice cover of floe that does not divide it into two or more pieces.
brackish ice	Ice formed from Brackish water.
stress	the intensity of two forces working against each other
chezy's roughness	a coefficient in Chezy's equation that accounts for energy loss due to the friction between the channel and the water.
sand wedge	A form of ice wedge that contains accumulations of wind blown sand in long vertical layers
wellhead protection area	a protected surface and subsurface zone surrounding a well or well field supplying a public water system to keep contaminants from reaching the well water.
coal	Sedimentary rock composed of the compacted, lithified and altered remains of plants
natural gas	Hydrocarbon based gas, mainly composed of methane, commonly found in the pores of sedimentary rocks of marine origin.
methane	A greenhouse gas produced by the decomposition of human and animal waste along with carbon based materials such as coal, petroleum and bogs.
mean sea-level	The average height of the ocean surface as determined from the mean of all tidal levels recorded at hourly intervals.
snow	snow pellets, snow grains, and ice crystals
solar zenith angle	The angle at the earth's surface measured between the Sun and an observer's zenith.
irrigation	The controlled application of water to arable lands to supply water requirements not satisfied by rainfall.
adsorption	the adhesion of a substance to the surface of a solid or liquid
volcanic cone	a conical mountain built up by volcanic eruptions
carbonation	Is a form of chemical weathering where carbonate and bicarbonate ions react with minerals that contain calcium, magnesium, potassium, and sodium.
wind speed	The rate of the motion of the air on a unit of time
haploid	Cell that contains only one set of chromosomes
fire tornado	During a natural or prescribed fire, the flames drastically heat the surface which allows for hot air near the surface to rise
organelle	Is a specialized structure found in cells that carry out distinct cellular functions.
freezing rain	Rain, the drops of which freeze on impact with the ground or with objects at or near the ground.
*squall line	A solid or nearly solid line or band of active thunderstorms.
blackwater	wastewater from toilet, latrine, and agua privy flushing and sinks used for food preparation or disposal of chemical or chemical-biological ingredients.
non-renewable resource	Resource that is finite in quantity and is being used faster than its ability to regenerate itself.
fire weather	Weather conditions leading to an increased risk of wildfires.
pressure	Is defined as the force acting on a surface from another mass per unit area.
freezing rain	Rain that falls in liquid form but freezes upon impact to form a coating of glaze on the ground and on exposed objects.
core	The core is a layer rich in iron and nickel found in the interior of the Earth
soil erodibility	An indicator of a soil's susceptibility to raindrop impact, runoff, and other eroding processes.
background extinction	Normal extinction of species that occurs as a result of changes in local environmental conditions
inceptisols	Soil order (type) of the United States Natural Resources Conservation Service Soil Classification System
biosphere	Part of the Earth where life is found
fossil fuel	Carbon based remains of organic matter that has been geologically transformed into coal, oil and natural gas
river left	Left side of the river when facing downstream.
hard water	water containing a high level of calcium, magnesium, and other minerals
energy	The capacity to do work
calibration error	The inaccuracy that the manufacturer permits when the unit is calibrated in the factory.
hydrocarbons	Compounds made of hydrogen and carbon atoms.
strike	One of the directional properties of a geologic structure such as a fold or a fault
head loss	In hydrologic terms, the decrease in total head caused by friction
inversion	A term meaning the reversal of something, in meteorology the a reversal of the normal atmospheric temperature gradient with height.
revolve	To move in a circle around a central point or line.
heavy freezing spray warning	A warning for an accumulation of freezing water droplets on a vessel at a rate of 2 cm per hour or greater caused by some appropriate combination of cold water, wind, cold air temperature, and vessel movement.
spatial	pertaining to space, or pertaining to distance such as spatial variation (variation over distance).
commensialism	Biological interaction between tospecies where one species benefits in terms of fitness while they other experiences no effect on its fitness.
vapor pressure	The pressure exerted by the molecules of a given vapor
liner	a relatively impermeable barrier designed to keep leachate inside a landfill; an insert or sleeve for sewer pipes to prevent leakage or infiltration.
indicator tests	tests for a specific contaminant, group of contaminants, or constituent which signals the presence of something else (ex., coliforms indicate the presence of pathogenic bacteria).
velocity	The change of direction and position of an object with time.
vorticity	A measure of the amount of "spin" (or rotation) in the atmosphere.
genetic diversity	Genetic variability found in a population of a species or all of the populations of a species
anthropogenic	Resulting from human activities.
microclimate	the local climate near the ground that is peculiar to a small area (usually, the radius is less than a kilometer, and can be as small as a centimeter)
seed	Fertilized ovule of a plant that contains an embryo and food products for germination
fossils	The mineralised remains of plants and animals embedded in rocks.
archipelago	A group of islands.
silicate magma	Magma that is felsic in composition.
dco	Defense Coordinating Officer
perihelion	The point on the Earth's orbit when it is closest to the Sun.
geologist	a scientist who studies the origin, history, structure, and processes of the earth
ground water mining	Pumping ground water from a basin where the safe yield is very small, thereby extracting ground water which had accumulated over a long period of time.
sidereal	Relative to the stars.
latitude	Latitude is a north-south measurement of position on the Earth
geopotential	Is equivalent to the potential energy of unit mass relative to a standard level (mean sea-level by convention) and is numerically equal to the work which would be done against gravity in raising the unit mass from mean sea-level to the level at which the mass is located
mass wasting	General term that describes the downslope movement of sediment, soil, and rock material.
hydrostatic head	a measure of pressure at a given point in a liquid in terms of the vertical height of a column of the same liquid which would produce the same pressure.
layline	An imaginary line projecting at an angle corresponding to the wind direction from either side of a racecourse marker buoy that defines the optimum sailing angle for a yacht to fetch the mark or the finish line
emergency operations center	The county facility that serves as a central location for the coordination and control of all emergency preparedness and response.
batholith	A large mass of subsurface intrusive igneous rock that has its origins from mantle magma.
basic solution	Any water solution that is basic (pH greater than 7) or has less hydrogen ions (H+) than hydroxide ions (OH-)
stretch	A portion of river located between two points; a section.
ndpo	FBI’s National Domestic Preparedness Office
hydrologic cycle	Water Equivalent
progradation	The natural extension of a shoreline seaward.
organism	any form of animal or plant life.
cg	(Some claim to have observed a relationship between staccato lightning and positive CGs, but this relationship is as yet unproven.)
per capita use	the average amount of water used per person during a standard time period, generally per day.
solonetzic soil	Soil order (type) of the Canadian System of Soil Classification
cyanobacteria	Bacteria that have the ability to photosynthesize.
apogee	The point farthest from the earth on the moon's orbit
soil taxonomy	The classification of a soil in a hierarchical system based on its various properties
experiment	A controlled investigation designed to evaluate the outcomes of causal manipulations on some system of interest.
brash ice	Accumulation of floating ice made up of fragments not more than 2 meters across; the wreckage of other forms of ice.
rain foot	[Slang], a horizontal bulging near the surface in a precipitation shaft, forming a foot-shaped prominence
death toll	the total number of people who die as a result of a disaster
specific conductance	a measure of the ability of water to conduct an electrical current as measured using a 1-cm cell and expressed in units of electrical conductance, i.e., Siemens per centimeter at 25 degrees Celsius
troposphere	The lowest layer of the atmosphere located between the earth's surface to approximately 11 miles (17 kilometers) into the atmosphere
volume	The occupation of space in three dimensions
isotherm	Lines on a map joining points of equal temperature.
celestial equator	The projection of the plane of the geographical equator upon the celestial sphere.
cloud	Cosmic Rays
area of influence	The area covered by the drawdown curves of a given pumping well or combination of wells at a particular time.
bifurcation ratio	Quantitative ratio determined between the parts of systems that display branching
ten-man raft	A boat 8 by 16 feet that will accommodate four to six people
ozone	A form of oxygen containing 3 molecules, usually found in the stratosphere, and responsible for filtering out much of the sun's ultraviolet radiation.
ferricretes	Sedimentary rock created by the chemical precipitation of iron.
isobars	A line drawn on a weather map connecting points of equal pressure
calibration	to check, adjust, or determine by comparison that a computer model will produce results that meet or exceed some defined criteria within a specified degree of confidence.
specific gravity	The ratio of the mass of a body to the mass of an identical volume of water at a specific temperature.
detention storage	The volume of water, other than depression storage, existing on the land surface as flowing water which has not yet reached the channel.
thpo	Tribal Historic Preservation Officer (refers to activities on native American tribal lands)
recurrence interval	The average amount of time between events of a given magnitude
pathogen	a disease-producing agent; usually applied to a living organism
sun dog	Either of two colored luminous spots that appear at roughly 22° on both sides of the sun at the same elevation
schist	A medium to coarse grained metamorphic rock with well developed bedding planes derived from the foliated recrystrallization of platy like minerals like mica.
spring tide	Semi-monthly tide of increased height due to the new or full moon.
irisation	Colors appearing on clouds, sometimes mingled, sometimes in the form of bands nearly parallel to the margins of the clouds
calculate	Perform mathematical operations.
tundra	High latitude biome dominated by a few species of dwarf shrubs, a few grasses, sedges, lichens, and mosses
hydraulic gradient	The slope of the water table or aquifer
photometer	Any of a number of atmospheric phenomena which appear as luminous patterns in the sky
j-rig	A pontoon-sized raft formed by joining several giant snout-nosedsponsons.
environment	The sum total of all the external conditions that effect an organism, community, material, or energy.
cirrus	High-level clouds (16,000 feet or more), composed of ice crystals and appearing in the form of white, delicate filaments or white or mostly white patches or narrow bands
emergency action plan	A predetermined plan of action to be taken to reduce the potential for property damage and loss of life in an area affected by a dam break or excessive spillway release.
confined groundwater	Groundwater trapped between two impervious layers of rock.
hmru	Hazardous Materials Response Unit
tilt sequence	Radar term indicating that the radar antenna is scanning through a series of antenna elevations in order to obtain a volume scan.
natural disaster	any terrible event, not caused by human activity, that results in deaths, injuries, or damage to property
river ice statement	A public product issued by the RFC's containing narrative and numeric information on river ice conditions.
industrial revolution	Major change in the economy and society of humans brought on by the use of machines and the efficient production of goods
sounding	Calculation of the convective temperature involves many assumptions, such that thunderstorms sometimes develop well before or well after the convective temperature is reached (or may not develop at all)
phreatic surface	The free surface of ground water at atmospheric pressure.
flash flood guidance	An internal product produced by the RFCs containing rainfall threshold values which must be exceeded in order to produce a flash flood.
biosphere	The transition zone between the earth and the atmosphere within which most terrestrial life forms are found
spatial isolation	Reproductive isolation of two or more populations of a species by distance or physical barriers
squall line	A line of intense thunderstorm cells parallel to and ahead of a fast-moving well-defined cold front.
wetting and drying	Physical weathering process where rocks are mechanically disintegrated by the accumulation of successive layers of water molecules in between the mineral grains of a rock
breakup period	The period of disintegration of an ice cover.
updraft	The cumulus towers that often are part of, or lead to thunderstorms.
ground fog	Fog produced over the land by the cooling of the lower atmosphere as it comes in contact with the ground
stability	The capability of a system to tolerate or recover from disturbance or an environmental stress.
threshold	The level of magnitude of a system process at which sudden or rapid change occurs.
hydropower	electrical energy produced by falling water.
phosphorous	a plant nutrient that can cause an overabundance of bacteria and algae when high amounts are present, leading to a depletion of oxygen and fish kills
spodosols	Soil order (type) of the United States Natural Resources Conservation Service Soil Classification System
drainage density	The relative density of natural drainage channels in a given area
nitrate	Form of nitrogen commonly found in the soil and used by plants for building amino acids, DNA and proteins
moraine	A hill of glacial till deposited directly by a glacier.
consolidated ice cover	Ice cover formed by the packing and freezing together of floes, brash ice and other forms of floating ice.
rain gauge	Instrument that measures the rain that falls at a location over a period of time.
high	An area of high pressure around which the wind blows clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere.
geoid	True shape of the Earth, which deviates from a perfect sphere because of a slight bulge at the equator.
squall line	A narrow band or line of active thunderstorms that is not associated with a cold front
kinetic energy	energy possessed by a moving object or water body.
heavy freezing spray warning	Usually issued for shipping interests when conditions are favorable for the rapid freezing of sea spray on vessels at a rate of more than 2 centimetres (0.79 in) per hour.
latosol	Soil order (type) of the United States Natural Resources Conservation Service Soil Classification System
geographic range	Spatial distribution of a species
rate	A fixed ratio between two things.
inclined staff gage	A staff gage that is placed on the slope of a stream bank and graduated so that the scale reads directly in vertical depth.
rigging	The wires, lines, halyards, and other items used to attach the sails and the spars to the boat
thermal metamorphism	Is the metamorphic alteration of rock because of intense heat released from processes related to plate tectonics.
power	the amount of work or energy expended in a given amount of time
leaching	the process by which soluble materials in the soil, such as salts, nutrients, pesticide chemicals or contaminants, are washed into a lower layer of soil or are dissolved and carried away by water.
north magnetic pole	Location in the Northern Hemisphere where the lines of force from Earth's magnetic field are vertical
catchment area	An area having a common outlet for its surface runoff (also see Drainage Area or Basin, Watershed).
volcanic vent	An opening on a volcano through which lava is released and rock fragments and ash are ejected.
elastic deformation	Change in the shape of a material as the result of the force of compression or expansion
sulfur trioxide	Released into the atmosphere primarily through the burning of fossil fuels that contain sulfur.
perched groundwater	Local saturated zones above the water table which exist above an impervious layer of limited extent.
squall line	A solid or nearly solid line or band of active thunderstorms.
cyclogenesis	Process of cyclone formation, maturation, and death.
mass number	Total number of neutrons and protons in the nucleus of an atom
output	Movement of matter, energy, or information out of a system
bar screen	in wastewater treatment, a device used to remove large solids from the incoming wastewater stream.
it	Information technology
oxidation	a chemical reaction involving the combination of a material with oxygen.
ground water runoff	That part of the runoff which has passed into the ground, has become ground water, and has been discharged into a stream channel as spring, or seepage water.
left bank	Left side of the river when facing downstream.
equator	Line of latitude at 0 degrees -- equal distance from both poles.
o horizon	Topmost layer of most soils
milky way galaxy	Aggregation of about 400 billion stars in a flattened, disk-shaped structure in space
longshore current	A water current that moves parallel to the shoreline.
hydrolysis	the decomposition of organic compounds by interaction with water.
propagule	Structure that develops into a plant.
lowest astronomical tide	The lowest tide level that can be predicted to occur under average meteorological conditions and any combination of astronomical conditions
eccentricity	The deviation of an ellipse from a perfect circular shape.
river	A long narrow channel of water that flows as a function of gravity and elevation across the Earth's surface
segregated ice	A form of periglacial ground ice that consists of almost pure ice that often exists as an extensive horizontal layer
equilibrium time	The time when flow conditions become substantially equal to those corresponding to equilibrium discharge or equilibrium drawdown.
incremental	The process of increasing in number, size, quantity, or extent.
radar	An instrument used for detecting the presence and distance of objects, such as rain drops, by scattering radio energy.
shear stress	Stress caused by forces operating parallel to each other but in opposite directions.
pedogenesis	Process of soil formation.
latitude	The angular distance in degrees, minutes and seconds measured from the center of the Earth to a point north and south of the Equator
forest	Ecosystem dominated by trees
wrapped	Said of a raft pinned flat around a rock or other obstruction by the current.
electromagnetic energy	Energy stored in electromagnetic waves or radiation
trade winds	easterly-blowing winds that are found on either side of the equator and blow northeasterly in the Northern Hemisphere and southeasterly in the Southern Hemisphere
discharge table	(1) A table showing the relation between two mutually dependant quantities or variable over a given range of magnitude
espinit	ESP Initialization Program
grout curtain	A barrier produced by injecting grout into a vertical zone, usually narrow (horizontally), and in the foundation to reduce seepage under a dam.
steppe	Grasslands spreading from central Europe to Siberia.
throughfall	Describes the process of precipitation passing through the plant canopy
radioisotope or radioactive isotope	A unstable isotope of an element
probe line	a line of 20 to 30 people, standing elbow to elbow, who advanced up a slope, poking into the snow with long poles in an effort to find victims buried by an avalanche
orogenesis	The process of mountain building through tectonic forces of compression and volcanism.
interbasin transfer	The physical transfer of water from one watershed to another.
unconfined groundwater	Groundwater that is not restricted by impervious layers of rock.
chemical autotroph	Organism that uses the external energy found in chemical compounds to produce food molecules
vegetation	all the trees and plants that grow in a particular area
representative fraction	The expression of map scale as a mathematical ratio.
air	comprising 0.033% of the total.
talik	An unfrozen section of ground found above, below, or within a layer of discontinuous permafrost
micronutrient	Nutritional element required by an organism in relatively very small quantities.
headgate	the gate that controls water flow into irrigation canals and ditches
siltstone	Fine grained sedimentary rock composed of lithified silt particles.
infiltration	the penetration of water through the ground surface into sub-surface soil or the penetration of water from the soil into sewer or other pipes through defective joints, connections, or manhole walls.
environmental indicator	a measurement, statistic or value that provides evidence of the effects of environmental management programs or of the state or condition of the environment.
scarification	Extensive movements of soil, sediment, and rock material caused by humans.
duration	In wave forecasting, the length of time the wind blows in nearly the same direction over the fetch, or "generating area."
wave period	The time elapsed for a wave to travel the distance of one wavelength.
tarn	A small mountain lake that occurs inside a cirque basin.
channel	A raftable route through a section of river.
solar irradiance	the amount of solar energy that arrives at a specific area of a surface during a specific time interval (radiant flux density)
point source	source of pollution that involves discharge of wastes from an identifiable point, such as a smokestack or sewage treatment plant
continental effect	The effect that continental surfaces have on the climate of locations or regions
haze	An aggregation in the atmosphere of very fine, widely dispersed, solid or liquid particles, or both, giving the air an opalescent appearance that subdues colors.
reservoir	A man-made facility for the storage, regulation and controlled release of water.
plastic deformation	Irreversible change in the shape of a material without fracture as the result of the force of compression or expansion.
diploid	Cell that contains two sets of chromosomes
prime meridian	The location from which meridians of longitude are measured
numerical prediction model	a computer program that mathematically duplicates conditions in nature
newton's law of gravity	The gravitational force between a pair of objects.
tolerance range	Limits of tolerance a species has to an abiotic factor or condition in the environment.
inert waste	waste that does not contain hazardous waste or soluble pollutants at concentrations in excess of applicable water quality objectives, and does not contain significant quantities of decomposable waste.
pyranometer	The standard instrument for measuring solar radiation incident on a horizontal surface; calibrates the temperature response of a special sensor in units of radiation flux.
craton	Stable foundation core of the Earth's various plates of continental crust
hygroscopic coefficient	Maximum limit of hygroscopic water around the surface of a soil particle.
head loss	The decrease in total head caused by friction, entrance and exit losses.
pollutant	A substance that has a harmful effect on the health, survival, or activities of humans or other living organisms.
detachment	One of three distinct processes involved in erosion
map projection	Cartographic process used to represent the Earth's three-dimensional surface onto a two-dimension map
mie scattering	Produced by spherical particles having the same diameter as the wavelength of visible light; light is scattered equally at all wavelengths.
slurry	a watery mixture of insoluble matter resulting from some pollution control techniques.
ionosphere	where temperatures drop rapidly with increasing height
fresh water	Water that is relatively free of salts.
intangible flood damage	Estimates of the damage done by disruption of business, danger to health, shock, and loss of life and in general all costs not directly measurable which require a large element of judgment for estimating.
fracturing	Deformation process whereby ice is permanently deformed, and fracture occurs.
sand	Particulate material resulting from rock disintegration, with no connotation as to composition
hanging wall	The topmost surface of an inclined fault.
lava	Molten magma released from a volcanic vent or fissure.
multi-cell thunderstorm	A thunderstorm consisting of two or more cells, of which most or all are often visible at a given time as distinct domes or towers in various stages of development
aquifuge	A geologic formation which has no interconnected openings and cannot hold or transmit water.
evaporate	To change from a liquid to a gas.
bannwalder	an area of woodland in an avalanche zone, which cannot be cut or disturbed because it is a natural barrier to avalanches
unit hydrograph theory	Unit Hydrograph Theory states that surface runoff hydrographs for storm events of the same duration will have the same shape, and the ordinates of the hydrograph will be proportional to the ordinates of the unit hydrograph
inhibition model of succession	This model of succession suggests that the change in plant species dominance over time is caused by death and small scale disturbances and variations is plant species longevity and ability to disperse
hollow-column	a snowflake in the shape of a long, six-sided column.
condensation	The change in state of matter from vapor to liquid that occurs with cooling
slate	A fine grained metamorphic rock with well developed bedding planes derived from the slight recrystrallization of shale.
ecliptic	The sun's apparent path across the sky that tracks a circle through the celestial sphere.
trade winds	Prevailing planetary-scale surface winds in tropical latitudes; blow from the northeast in the Northern Hemisphere and from the southeast in the Southern Hemisphere.
isopleth	A line on a map connecting locations with the same value of a variable.
hydrograph	In hydrologic terms, a graph showing the water level (stage), discharge, or other property of a river volume with respect to time.
valley breeze	Local thermal circulation pattern found in areas of topographic relief
absolute zero	Considered to be the point at which theoretically no molecular activity exists or the temperature at which the volume of a perfect gas vanishes
laccolith	A blister of magma that forces the overlying rocks into a dome.
drainage reuse	reuse of agricultural drainage on salt-tolerant crops.
terminal fall velocity	Velocity at which a particle being transported by wind or water falls out of the moving medium
shield volcano	Volcano created from alternate layers of lava flows
ascend	To go up or rise.
urban area	Geographic area with a high density of people over a limited area
wettable powder	dry formulation that must be mixed with water or other liquid before it is applied.
obliquity	Obliquity is the angle between a planet's equatorial plane and its orbital plane.
import	Water piped or channeled into an area.
proton	A sub-particle of an atom that contains a positive charge.
bioassay	a test to determine the relative strength of a substance by comparing its effect on a test organism with that of a standard preparation.
ogee	A reverse curve, shaped like an elongated letter S
scenario	Description of how the future may develop, based on a coherent and internally consistent set of assumptions about key relationships and driving forces.
transparency	The ability of a medium to allow light to pass through it.
aftershocks	smaller quakes that follow a major earthquake
"nice looking rubbber"	One of the higher compliments that can he paid a raft.
transport	One of three distinct processes involved in erosion
irrigation efficiency	The percentage of water applied that can be accounted for in soil moisture increase for consumptive use.
stern	The rear of the boat.
rectangular coordinate system	System that measures the location of points on the Earth on a two-dimensional coordinate plane
pediment	A gradually sloping bedrock surface located at the base of fluvial-eroded mountain range
flashover	when burning objects heat walls and other objects in an enclosed area to their ignition temperature, causing them to flame; marked by large increase in flame volume and a sudden, marked rise in gas temperature
foreshock	a small tremor before a major earthquake
actinometer	An instrument which measures the intensity of radiation by determining the amount of chemical change or fluorescence produced by that radiation.
density	An example is a baroclinic pattern.
ferry	A maneuver for moving a boat laterally across a current
magnitude	the power of an earthquake.
antenna gain	See gain.
oml	An Operations Manual Letter
pore ice	A form of periglacial ground ice that is found in the spaces that exist between particles of soil.
equator	which is designated at zero (0) degrees
turning point	In hydrologic terms, a temporary point whose elevation is determined by additions and subtractions of backsights and foresights respectively.
aspirator	A device attached to a meteorological instrument to provide ventilation; usually a suction fan.
sublimation	The process whereby water changes phase from a solid into a vapor without first becoming liquid.
active volcano	a volcano that continues to erupt regularly.
isotope	Form of an element where the number of neutrons in its atomic nucleus is different than the number of protons.
infrared radiation	Form of electromagnetic radiation with a wavelength between 0.7 and 100 micrometers (µm)
cumulus	Puffy white or light grey clouds with a flat base and a sharp outline, often resembling a floating cotton balls
cement grout	a mixture of water and cement in the ratio of not more than 5-6 gallons of water to a 94 pound sack of portland cement which is fluid enough to be pumped through a small diameter pipe.
planum	An IAU geographical feature name meaning “high plain” or “plateau.”
absorption	when the substance of interest is captured by another substance, reducing the amount available
foresight	A sighting on a point of unknown elevation from an instrument of known elevation
plantae	Group, at the kingdom level, in the classification of life
moderate flooding	The inundation of secondary roads; transfer to higher elevation necessary to save property -- some evacuation may be required.
calorie	Quantity of energy
hydraulic head	(1) The height of the free surface of a body of water above a given point beneath the surface
jet entrance/exit	This is an area observed in upper air data, usually using the wind field, where the upper winds accelerate and decelerate notably. This acceleration and deceleration is around the core of the jet stream or a jet streak. These areas have a direct impact on the weather at the surface. A right jet entrance area and a left jet exit area indicate cyclogenesis at the surface, while a left jet entrance and a right jet exit indicate anticyclonic development at the surface.
exfoliation dome	A physical weathering feature associated with granite that is the result of the erosion of overburden material and pressure-release
self-regulation	The ability of some systems to maintain a steady state equilibrium through positive and negative feedbacks.
riparian water rights	the rights of an owner whose land abuts water
pervious zone	A part of the cross section of an embankment dam comprising material of high permeability.
temperature	Temperature is defined as the measure of the average speed of atoms and molecules
terminate	To reach an end point or line.
sludge	solid matter that settles to the bottom of sedimentation tanks in a sewage treatment plant and must be disposed of by digestion or other methods or recycled to the land.
negative feedback	Change in the state of a system that counteracts the measured effect of the initial alteration.
saturation	the condition of a liquid when it has taken into solution the maximum possible quantity of a given substance at a given temperature and pressure.
denitrification	Conversion of nitrates into gaseous nitrogen and nitrous oxide.
observation well	A non-pumping well used for observing the elevation of the water table or piezometric surface.
eruption	the release of pressure that sends lava, rocks, ash, and gases out of a volcano.
static equilibrium	Static equilibrium occurs where force and reaction are balanced and the properties of the system remain unchanged over time.
gross sediment transport	The total amount of sediment transported along a shoreline in a specific time period.
radiation	Energy that moves through space or a medium in the form of a wave with electric and magnetic fields
rock flour	Very finely ground rock fragments that form between the base of a glacier and the underlying bedrock surface.
dendrochronology	the science of studying tree rings
metamorphism	Process that creates metamorphic rocks.
shoreline	The line that separates a land surface from a water body
saltation	the wind-driven movement of particles along the ground and through the air.
surface tension	the attraction of molecules to each other on a liquid's surface
cation exchange capacity	The capacity of a soil to exchange cations with the soil solution
instantaneous unit hydrograph	The theoretical, ideal, unit hydrograph that has a infinitesimal duration.
heat cramps	muscle cramps or spasms, usually afflicting the abdomen or legs, caused by exercising in hot weather.
homosphere	The atmosphere up to 80 km (50 mi) in which the proportions of principal gases, such as oxygen and nitrogen, are constant.
chemosynthesis	Process in which specific autotrophic organisms extract inorganic compounds from their environment and convert them into organic nutrient compounds without the use of sunlight
greenhouse effect	Warming of the atmosphere by slowing the release of heat to space, due to greenhouse gases such as carbon dioxide and methane.
breaker	The quick collapse of an overextended water wave as it approaches the shoreline
extratropical cyclone	A cyclone in the middle and high latitudes, often being 2000 kilometers in diameter and usually containing a cold front that extends toward the equator for hundreds of kilometers
ultraviolet radiation	Electromagnetic radiation with wavelengths between approximately .2 to .4 microns.
synoptic surveillance track	Weather reconnaissance mission flown to provide vital meteorological information in data-sparse ocean areas as a supplement to existing surface, radar and satellite data
pressure	The force exerted by the interaction of the atmosphere and gravity
altocumulus castellanus	A type of altocumulus cloud with tower-like projections that billow upwards from the base of the cloud
prior appropriation doctrine	the system for allocating water to private individuals used in most Western states
mesoscale convective complex	A cluster of thunderstorms covering an area of 100,000 kilometers or more
soil organic matter	Organic constituents of soil.
surface impoundment	An indented area in the land's surface, such as a pit, pond, or lagoon.
knot	A unit for the measurement of speed in the nautical system
dead storage	The volume in a reservoir below the lowest controllable level.
rhyolite	A fine grained extrusive igneous rock that is rich in quartz and potassium feldspar
base station	A computer which accepts radio signals from ALERT gaging sites, decodes the data, places the data in a database, and makes the data available to other users.
macronutrient	Nutritional element required by an organism in relatively large quantities.
depth hoar	a layer of snow made up of round or cup-shaped crystals that act like ball bearings, allowing the layer of snow on top to slide of easily; also known as sugar snow
transient response	the short-term response of an instrument caused by a change of status of the instrument's environment
water well	any artificial excavation constructed for the purpose of exploring for or producing ground water.
standard solution	any solution in which the concentration is known.
map	An abstraction of the real world that is used to depict, analyze, store, and communicate spatially organized information about physical and cultural phenomena.
pressure gradient force	Phase
easy-rower washer	Large plastic, rubber, or metal washer placed between the oar and frame to reduce friction.
argon	A colorless, odorless inert gas that is the third most abundant constituent of dry air, comprising 0.93% of the total.
plume	the area taken up by contaminant(s) in an aquifer.
cloud	A visible collection of minute particle matter, such as water droplets and/or ice crystals, in the free air
random error	the difference between the actual and the desired quantity that varies randomly; that is, if a probability distribution of differences is produced, it is the Gaussian error function.
volcano	An opening in the Earth's crust through which molten magma and gases erupt
prokaryote	Organisms whose cells have their genetic material in the form of loose strands of DNA found in the cytoplasm
permanent control	A stream gaging control which is substantially unchanging and is not appreciably affected by scour, fill, or backwater.
sediment rating curve	Numerical expression or graphical curve that describes the quantitative relationship between stream discharge and the sediment transported by a particular stream.
rangeland	Land-use type that supplies vegetation for consumption by grazing and browsing animals
water equivalent	The amount of water, in inches, obtained by melting a snow sample.
heterotroph	Organism that must consume energy rich organic molecules for survival
almanac	A book containing a calendar and facts about the weather and general interests.
solar conversion technologies	collective name for all methods for converting the sun's energy into usable energy.
field mill	Instrument that measures the electric field through the current induced by electrodes moving on it
three-axis stabilized	Done with an internal gyroscope and thrusters
flood loss reduction measures	The strategy for reducing flood losses
d-ring	Metal, D-shaped ring attached to a raft and used to secure frames, lines, rope thwarts, etc.
pitch	A section of a rapid steeper than the Surrounding portions; a drop.
reserves	amount of a particular resource in known locations that can be extracted at a profit with present technology and prices.
climate	A pattern of weather in a region as measured over a long period of time
roml	Regional Operations Manual Letter
island arc	A line of volcanic islands found of the ocean that have been created by the convergence of two tectonic plates and the subsequent subduction of one of the plates beneath the other
irrigated area	The gross farm area upon which water is artificially applied for the production of crops, with no reduction for access roads, canals, or farm buildings.
hydroelectric power water use	the use of water in the generation of electricity at plants where the turbine generators are driven by falling water.
biomonitoring	a test used to evaluate the relative potency of a chemical by comparing its effect on a living organism with the effect of a standard population on the same type of organism.
hazardous weather outlook	A narrative statement produced by the National Weather Service, frequently issued on a routine basis, to provide information regarding the potential of significant weather expected during the next 1 to 5 days.
two-tailed statistical test	Is an inferential statistical test where the values for which one can reject the null hypothesis are located either side of the center of the probability distribution.
confined aquifer	Aquifer between two layers of relatively impermeable earth materials, such as clay or shale.
cirque	Glacially eroded rock basin found on mountains
swell	A relatively smooth ocean wave that travels some distance from the area of its generation.
gps	Global Position System
thematic map	Map that displays the geographical distribution of one phenomenon or the spatial associations that occur between a few phenomena
magma plume	A rising vertical mass of magma originating from the mantle.
diurnal	Daily, pertaining to actions completed within or that recur every 24 hours.
potential energy	Is the energy that a body possesses by virtue of its position and that is potentially transformable into another form of energy.
swe	Snow Water Equivalent
ahos	Automatic Hydrologic Observing System
monera	Group, at the kingdom level, in the classification of life
intercepting drain	A drain constructed at the upper end of the area to be drained, to intercept surface or ground water flowing toward the protected area from higher ground, and carry it away from the area
thermokarst	Landscape dominated by depressions, pits, and caves that is created by the thawing of ground ice in high latitude locations
ebris flow	A type of mass movement where there is a downslope flow of a saturated mass of soil, sediment, and rock debris.
dispersion	The process in which white light separates into its component colors.
utc	Abbreviation for Universal Time Coordinated and formerly known as Greenwich Mean Time (GMT).
system state	Current value of a system's elements, attributes, and/or relationships.
variable	Something that changes; a quantity that increases or decreases.
intertropical convergence zone	The axis dividing the southeast trades from the northeast trades, toward which the surface winds tend to converge
fertilizer	Substance that adds inorganic or organic nutrients to soil for the purpose of increasing the growth of crops, trees, or other vegetation.
meridional flow	A type of atmospheric circulation pattern in which the north and south component of motion is unusually pronounced
permafrost	Zone of permanently frozen water found in high latitude soils and sediments
reflection	The process in which energy incident on the surface is turned back into the medium through which it originated.
acequia	acequias are gravity-driven waterways, similar in concept to a flume
groundwater storage	the storage of water in groundwater reservoirs.
lithification	Process by which sediments are consolidated into sedimentary rock.
angle of repose	angle at which material will remain stable
gallery	A passageway within the body of a dam or abutment.
plants	In this interaction, one species produces and releases of chemical substances that inhibit the growth of another species.
engineer's level	A telescope which is attached to a spirit-tube level, all revolving around a vertical axis and is mounted on a tripod
gradient	The slope of a river expressed in feet per mile.
lan	Local Area Network
reflectance	the fraction or percent of a particular frequency or wavelength of electromagnetic radiation that is reflected from the surface of a substance without being absorbed or transmitted.
kinetic energy	The energy due to motion.
bloom	a proliferation of algae and/or higher aquatic plants in a body of water; often related to pollution or excessive nutrients, especially when they accelerate growth.
lysimeter	Meteorological instrument used to measure potential and actual evapotranspiration.
albedo	The fraction or percent of radiation striking a surface that is reflected by that surface.
falls	A drop over which the water falls free at least part of the way.
phase change	Reorganization of a substance at the atomic or molecular level resulting in a change of the physical state of matter
lag	Lowest adjacent grade (to a structure)
km	Kilometers
rhumb line	A line of constant compass direction or bearing which crosses the meridians at the same angle
horizon	The distant line along which the earth and sky appear to meet
columnar ice	Ice consisting of columnar shaped grain
chaff	Small strips of metal foil, usually dropped in large quantities from aircraft or balloons in order to confuse enemy radar
anvil	They usually appear on the upwind side of a back-sheared anvil, and indicate rapid expansion of the anvil due to the presence of a very strong updraft
latitude	The location north or south in reference to the equator, which is designated at 0 degrees
solar absorber	a sheet of material, usually copper, aluminum, or steel that forms the surface of a solar collector
pressure or atmospheric pressure	The force exerted on an area by the weight of the atmosphere overhead.
oceanic ridge	A volcanic mountain chain formed at the boundary between two oceanic tectonic plates.
freezing rain	Supercooled raindrops that freeze on contact with cold surfaces.
continuous permafrost	Form of permafrost that exists across a landscape as an unbroken layer.
reflected infrared radiation	Form of electromagnetic radiation with a wavelength between 0.7 to 3.0 micrometers (µm).
potential energy	The energy an object has by virtue of its position.
effluent seepage	Diffuse discharge of ground water to the ground surface.
littoral transport	The process of sediment moving along a coastline
teleconnection	Linkage between changes in atmospheric circulation occurring in widely separated parts of the globe.
results act	Government Performance and Results Act
wet suit	A close-fitting garment of neoprene foam that provides thermal insulation in cold water.
scattered	Individual features that are widely distributed in extent and are likely to affect the area frequently.
hydraulic head	In hydrologic terms, (1) The height of the free surface of a body of water above a given point beneath the surface
heat advisory	Its issued within 12 hours of the onset of the following conditions: a heat index of at least 105 degrees but less than 115 degrees for less than 3 hours per day or if nighttime lows remain above 80 degrees for 2 consecutive days.
spreading center	An area where two plates are pulling away from each other
polycyclic landform	Landform that shows the repeated influence of one or more major geomorphic processes over geological time
occluded	Closed up or blocked off.
flood problems	Problems and damages that occur during a flood as a result of human development and actions
isobar	A line on a weather chart showing places having the same atmospheric pressure at the same time.
hydrograph	A graph showing the water level (stage), discharge, or other property of a river volume with respect to time.
hydrolysis	Chemical weathering process that involves the reaction between mineral ions and the ions of water (OH- and H+), and results in the decomposition of the rock surface by forming new compounds, and by increasing the pH of the solution involve through the release of the hydroxide ions.
mudstone	Fine grained sedimentary rock composed of lithified silt and clay particles.
tornado alley	A geographic corridor in the United States which stretches north from Texas to Nebraska and Iowa
rockslide	a cascade of rocks (of any size) down a steep slope at high speeds.
convergence	This is an area where winds/windfields converge
hypothesis	A tentative assumption that is made for the purpose of empirical scientific testing
homosphere	The lower layer in a two part classification of the atmosphere based on the general homogeneity of chemical composition
cinders	nut-sized pieces of red or black lava containing bubble-like cavities known as vesicles
wet floodproofing	An approach to floodproofing which usually is a last resort
discharge	the volume of water that passes a given point within a given period of time
plagioclase feldspar	A type of feldspar that is rich in sodium and calcium
aurora	It is created by the radiant energy emission from the sun and its interaction with the earth's upper atmosphere over the middle and high latitudes
cleat	A fitting, typically with projecting ends, that holds a line against the tension from the sails, rigging or mooring.
light	usually the visual portion of the electromagnetic spectrum between infrared (about 8000 Angstroms or 800 nanometers(nm)) and ultraviolet (about 4,000 Angstroms or 400 nm); however, the term is sometimes used as a synonym for all electromagnetic radiation.
pathogen	microorganisms which can cause disease.
sludge digester	tank in which complex organic substances like sewage sludge are biologically dredged
inconstant	Likely to change frequently without apparent reason.
detritus food chain	Model describing the conversion of organic energy in a community or ecosystem into inorganic elements and compounds through decomposition
state revolving funds	a program, capitalized in part by federal funds, that provides low-interest loans for construction of publicly owned wastewater treatment and water recycling facilities, for implementation of nonpoint source and storm drainage pollution control management programs, and for the development and implementation of estuary conservation and management programs.
hydrologic equation	The water inventory equation (Inflow = Outflow + Change in Storage) which expresses the basic principle that during a given time interval the total inflow to an area must equal the total outflow plus the net change in storage.
force	The mass of an object multiplied by the change in its speed and/or direction (acceleration).
barotropic	A barotropic atmosphere is one in which the pressure depends only on the density and vice versa, so that isobaric surfaces (constant pressure surfaces) are also isopycnic surfaces (constant density surfaces).
compound	A compound is the atoms of different elements joined together.
head	the pressure of a fluid owing to its elevation, usually expressed in feet of head or in pounds per square inch, since a measure of fluid pressure is the height of a fluid column above a given or known point.
eif	Enhanced IFLOWS Format
hydraulic mean depth	The right cross-sectional area of a stream of water divided by the length of that part of its periphery in contact with its containing conduit; the ratio of area to wetted perimeter
mollisols	Soil order (type) of the United States Natural Resources Conservation Service Soil Classification System
valve	A device fitted to a pipeline or orifice in which the closure member is either rotated or moved in some way as to control or stop flow.
emergency broadcast system	A system designed to permit government officials to issue up-to-date and continuous emergency information and instructions to the public in a threatened or actual emergency.
compute	To determine by mathematical means.
fish	Group of vertebrate animals that inhabit aquatic habitats.
critical low flow	low flow conditions below which some standards do not apply
vested water right	the right granted by a state water agency to use either surface or ground water.
gene pool	Sum total of all the genes found in the individuals of the population of a particular species.
cirrus	A high cloud composed of ice crystals in the form of thin, white, featherlike clouds in patches, filaments, or narrow bands.
symmetry	Close agreement in size, shape, and relative position of parts arranged on opposite sides of a dividing line.
desert pavement	A veneer of coarse particles left on the ground after the erosion of finer particles by wind.
standard deviation	A statistical measure of the dispersion of observation values in a data set
asthenosphere	the hot top part of the earth's mantle, just under the crust
divergence	The expansion or spreading out of a vector field; usually said of winds
basin boundary	The topographic dividing line around the perimeter of a basin, beyond which overland flow (i.e.; runoff) drains away into another basin.
windbreak	row of trees or shrubs placed in a farm field to slow the wind and keep it from blowing.
phylogenic classification	Classification of organisms based on genetic connections between other species.
parallel	A line parallel to the equator and connecting all places of the same latitude.
ozone layer	Atmospheric concentration of ozone found at an altitude of 10 to 50 kilometers above the Earth's surface
non-ionizing radiation	A form of electromagnetic radiation that does not have enough energy to cause ionization of atoms in living tissue
basket boat	A 10-man size military-surplus raft-constructed of an upper and a lower buoyancy tube; the upper tube flares outward, giving the boat a bowl- or basket-like appearance.
mesoscale convective system	A term often used to describe a cluster of thunderstorms that does not meet the size, duration, or shape criteria of an MCC
stratigraphy	Subdiscipline of geology that studies sequence, spacing, composition, and spatial distribution of sedimentary deposits and rocks.
shuttle	The process of moving vehicles from the put-in to the take-out or trip members in the reverse direction
predation	Biological interaction between species where a predator species consumes a prey species.