Weather terms starting with B

171 terms

B Abbreviation used on long-term climate outlooks issued by CPC to indicate areas that are likely to be below normal for a given parameter (temperature…
Back Door Cold Front A cold front moving south or southwest along the Atlantic seaboard and Great Lakes; these are especially common during the spring months.
Back-building Thunderstorm A thunderstorm in which new development takes place on the upwind side (usually the west or southwest side), such that the storm seems to remain…
Back-sheared Anvil [Slang], a thunderstorm anvil which spreads upwind, against the flow aloft. A back-sheared anvil often implies a very strong updraft and a high severe…
Backfire A fire started to stop an advancing fire by creating a burned area in its path.
Backflow A reverse flow condition, created by a difference in water pressures, which causes water to flow back into the distribution system.
Backing Any type of line used to partially fill a reel before the main fishing line is added; commonly used in fly-fishing or by bass anglers who use many of the…
Backing Winds Winds which shift in a counterclockwise direction with time at a given location (e.g.
Backscatter The portion of power scattered back in the incident direction.
backscatter depolarization ratio The ratio of cross polarized to co-polarized elastic backscatter.
backscattered radiation The scattering of radiant energy into the hemisphere of space bounded by a plane normal to the direction of the incident radiation and lying on the same…
Backsight A rod reading taken on a point of known elevation, a benchmark or a turning point.
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…
Backwater Effect The effect which a dam or other obstruction or construction has in raising the surface of the water upstream from it.
Backwater Flooding Upstream flooding caused by downstream conditions such as channel restriction and/ or high flow in a downstream confluence stream.
Bacteria (bak-TEER-ee-uh) A large group of single-cell microorganisms. Some cause infections and disease in animals and humans.
BAM Binary Angular Measure
BANDPASS FILTER A filter whose frequencies are between given upper and lower cutoff values, while substantially attenuating all frequencies outside these values (this…
Bandwidth The amount of information or data that can be sent over a network connection in a given period of time.
Bank America has a "dual banking system" which means that both states and the federal government issue bank charters for the need and convenience of their…
Bank Storage Water that has inflitrated from a reservoir into the surrounding land where it remains in storage until water level in the reservoir is lowered.
Bankfull The water level, or stage, at which a stream, river or lake is at the top of its banks and any further rise would result in water moving into the flood…
Bankfull Stage An established river stage at a certain point along a river which is intended to represent the maximum safe water level which will not overflow the river…
Banner Cloud A cloud plume often observed to extend downwind behind isolated mountain peaks, even on otherwise cloud-free days.
BAPSU Bay Area Public Service Unit. Public Service section of the San Francisco Bay Area Weather Service Forecast Office.
Bar 1. Historically, the partition separating the general public from the space occupied by the judges, lawyers and other participants in a trial. 2.
Barber Pole [Slang], a thunderstorm updraft with a visual appearance including cloud striations that are curved in a manner similar to the stripes of a barber pole.
Baroclinic leaf shield A cloud pattern on satellite images - frequently noted in advance of formation of a low pressure center.
Baroclinic Zone A region in which a temperature gradient exists on a constant pressure surface.
Baroclinity A measure of the state of stratification in a fluid in which surfaces of constant pressure (isobaric) intersect surfaces of constant density (isosteric).
Barogram An analog record of pressure produced by a barograph
Barograph A barometer that records its observations continuously.
Barometer An instrument that measures atmospheric pressure.
Barometric Pressure The pressure of the atmosphere as indicated by a barometer.
Barotropic System A weather system in which temperature and pressure surfaces are coincident, i.e.
Barotropy The state of a fluid in which surfaces of constant density (or temperature) are coincident with surfaces of constant pressure; it is the state of zero…
Barrage Any artificial obstruction placed in water to increase water level or divert it. Usually the idea is to control peak flow for later release.
Barrel A volumetric unit of measure for crude oil and petroleum products equivalent to 42 U.S. gallons.
Barrier Jet A jet-like wind current that forms when a stably-stratified low-level airflow approaches a mountain barrier and turns to the left to blow parallel to the…
Bartel's Rotation Number The serial number assigned to 27-day rotation periods of solar and geophysical parameters.
BASE DATA Those digital fields of reflectivity, mean radial velocity, and spectrum width data in spherical coordinates provided at the finest resolution available…
Base Flood The flood having a 1% chance of being equaled or exceeded in any given year.
BASE PRODUCTS Those products that present some representation of the base data. This representation may not necessarily be either in full resolution or depict the full…
Base Reflectivity One of the three fundamental quantities (along with base [radial] velocity and spectrum width) that a Doppler radar measures.
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…
Base Width The time duration of a unit hydrograph.
Baseflow Streamflow which results from precipitation that infiltrates into the soil and eventually moves through the soil to the stream channel.
Baseline Change Request (BCR) A web-based tool that is used to discuss, review, and approve an "engineered product" or other changes to infrastructure components as it is turned over…
Baseline Emissions The emissions that would occur without policy intervention (in a business-as-usual scenario).
Basic solution Water solution with more hydroxide ions (OH-) than hydrogen ions (H+); water solutions with pH greater than 7. See acid solution, alkalinity.
Basin : (1) A depression in the Earth's surface that collects sediment. (2) The area of land that drains to a particular river.
Basin Boundary The topographic dividing line around the perimeter of a basin, beyond which overland flow (i.e.; runoff) drains away into another basin.
Basin Lag The time it takes from the centroid of rainfall for the hydrograph to peak.
Basin Recharge Rainfall that adds to the residual moisture of the basin in order to help recharge the water deficit. i.
Bathymetry The science of measuring depths of the oceans, lakes, seas, etc.
BCKG Backing- A counterclockwise shift in wind direction (for example, south winds shifting to the east).
BCM Become
BCMNG Becoming
BD Blowing Dust
Beach Erosion The movement of beach materials by some combination of high waves, currents and tides, or wind.
BEAM FILLING The measure of variation of hydrometeor density throughout the radar sampling volume.
BEAM WIDTH Angular width of antenna pattern. Usually that width where the power density is one-half that of the axis beam. (Half-Power or 3 dB point)
Bear's Cage [Slang], a region of storm-scale rotation, in a thunderstorm, which is wrapped in heavy precipitation.
Beaufort Scale The Beaufort wind scale is a system used to estimate and report wind speeds when no measuring apparatus is available.
Beaver('s) Tail [Slang], a particular type of inflow band with a relatively broad, flat appearance suggestive of a beaver's tail.
Bed Load Sediment that moves by rolling or sliding along the bed and is essentially in contact with the streambed in the bed layer.
Beginning of Freezup Date on which ice forming a stable winter ice cover is first observed on the water surface.
Beginning of the Breakup Date of definite breaking, movement, or melting of ice cover or significant rise of water level.
Benchmark A standard unit used as the basis of comparison; a universal unit that is identified with sufficient detail so that other similar classifications can be…
benthic foraminifera single-celled animals that live near the sediment water interface and have calcium carbonate skeletons.
Bergeron Process The process by which ice crystals in a cloud grow at the expense of supercooled liquid water droplets.
Bergy Bit A piece of ice which has broken away from an iceberg, extending 1-5 meters above the sea surface and 100-300 square meters in area.
Berlin Mandate A ruling negotiated at the first Conference of the Parties (COP 1), which took place in March, 1995, concluding that the present commitments under the…
Bermuda High A semi-permanent, subtropical area of high pressure in the North Atlantic Ocean off the East Coast of North America that migrates east and west with…
Best Track A subjectively-smoothed representation of a tropical cyclone's location and intensity over its lifetime.
BFR Before
BGN Begin
BHND Behind
bias (BY-us) In a scientific research study or clinical trial, a flaw in the study design or the method of collecting or interpreting information.
Billow Cloud A cloud consisting of broad parallel bands oriented perpendicular to the wind.
BIN Radar sample volume.
BINOVC Breaks in Overcast
Biodegradable Capable of being biodegraded.
Biofuel A gaseous, liquid or solid fuel derived from a biological source, e.g. ethanol, rapeseed oil or fish liver oil.
Biogeochemical Cycle Movements through the Earth system of key chemical constituents essential to life, such as carbon, nitrogen, oxygen, and phosphorus.
Biological oxygen demand (Abbreviation: BOD). The dissolved oxygen required for the respiration of a population of aerobic organisms present in water.
Biomass The aggregate amount of living matter or a specific species within a specific habitat, or the total number of a specific species in a specific habitat.
Biomass energy Energy produced by the conversion of biomass directly to heat or to a liquid or gas that can be converted to energy.
Biosphere The part of the earth and its atmosphere that is inhabited by living organisms.
Biotic Pertaining to life or living organisms.
bipolar see-saw the occurrence of warm temperatures in the Southern Hemisphere while temperatures in the Northern Hemisphere are colder-than-average, or vice versa.
Bitumen Gooey, black, high-sulfur, heavy oil extracted from tar sand and then upgraded to synthetic fuel oil. See tar sand.
Bituminous coal A dense, black, soft coal, often with well-defined bands of bright and dull material.
BKN Broken
BL Abbreviation for Boundary Layer; a layer of air adjacent to a bounding surface.
Black Body A hypothetical object that absorbs all of the radiation that strikes it; also emits radiation at a maximum rate for its given temperature.
Black Carbon Operationally defined species based on measurement of light absorption and chemical reactivity and/or thermal stability; consists of soot, charcoal…
black carbon concentration The concentration of carbon in its very absorbing, elemental, non-organic, non-oxide form (e.g. graphite).
Black Ice Transparent ice formed in rivers and lakes, or on roads and bridges.
Blackbody An ideal substance that absorbs all radiation falling on it, and reflecting nothing.