Aeronautical Terms beginning with B

Backing

Shifting of the wind in a counterclockwise direction with respect to either space or time; opposite of veering. Commonly used by meteorologists to refer to a cyclonic shift (counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere).

Backscatter

Pertaining to radar, the energy reflected or scattered by a target; an echo.

Banner cloud (also called cloud banner)

A banner-like cloud streaming off from a mountain peak.

Barograph

A continuous-recording barometer.

Barometer

An instrument for measuring the pressure of the atmosphere; the two principle types are mercurial and aneroid.

Barometric altimeter

Also called a pressure altimeter. An aneroid barometer with a scale graduated in altitude instead of pressure using standard atmospheric pressure-height relationships; shows indicated altitude (not necessarily true altitude); may be set to measure altitude (indicated) from any arbitrarily chosen level.

Barometric pressure

Same as atmospheric pressure—the pressure exerted by the atmosphere as a consequence of gravitational attraction exerted upon the “column” of air lying directly above the point in question.

Barometric tendency

The change of barometric pressure within a specified period of time. In aviation weather observation, routinely determined periodically, usually for a 3-hour period.

Beaufort scale

A scale of wind speeds.

Black blizzard

Same as dust storm—an unusual, frequently severe weather condition characterized by strong winds and dust-filled air over an extensive area.

Blizzard

A severe weather condition characterized by low temperatures and strong winds bearing a great amount of snow, either falling or picked up from the ground.

Blowing dust

A type of lithometeor composed of dust particles picked up locally from the surface and blown about in clouds or sheets.

Blowing sand

A type of lithometeor composed of sand picked up locally from the surface and blown about in clouds or sheets.

Blowing snow

A type of hydrometeor composed of snow picked up from the surface by the wind and carried to a height of 6 feet or more.

Blowing spray

A type of hydrometeor composed of water particles picked up by the wind from the surface of a large body of water.

Bright band

In radar meteorology, a narrow, intense echo on the range-height indicator scope resulting from water-covered ice particles of high reflectivity at the melting level.