Wind with a speed between 41 and 47 knots (47 and 54 mph); Beaufort scale number 9.

An instrument for measuring the intensity of direct solar radiation at normal incidence. See Angstrom compensation pyrheliometer, Eppley pyrheliometer, Michaelson actinograph. silver- disc pyrheliometer, spectropyrheliometer, waterflow pyrheliometer.

A protective coating applied to circuits.

The ratio of the output of an instrument to the input value, i.e. a rain gauge with a sensitivity of 1 tip per 0.01"

Lacking a relationship to a time base or clock. In asynchronous communications, individual data characters are sent at an arbitrary rate.

A system of designating meteorological observing stations by number. established and administered by the World Meteorological Organization. Under this scheme, specified areas of the word are divided into "blocks" each bearing a two-number designator. Stat ...

Movernent of water through the soil surface into the soil, or the quantity of water entering the soil. Infiltration is equal to the total precipitation less the losses due to interception by vegetation. retention in depressions on the land surface, evapor ...

An increase or amplification. There are two general usages of the term in radar meteorology: (a) antenna gain (or gain factor) is the ratio of the power transmitted along the beam axis to that of an isotropic radiator transmitting the same total power; an ...

in folklore, a name for fire.

The mean difference between the readings of a given instrument and those of a standard instrument.

An anemometer utilizing the principle that the pitch of the aeolian tones generated by air moving past an obstacle is a function of the speed of the air. Largely a curiosity and has been put to no practical application in modem meteorology.

A mercury-in-glass thermometer which records the temperature upon being inverted and retains its reading until being returned to the first position.

A line drawn through geographical points where a given seasonal biological event occurs on the same date.

Operation mode of a communication circuit in which one end can only transmit and the other end can only receive.

The succession of stages through which water passes on the ground and in the atmosphere: evaporation from land or bodies of water, condensation to form clouds, precipitation, accumulation in the soil or in bodies of water, and re-evaporation.

Federal Aviation Administration.

Any quantity, such as force velocity, or acceleration, which has both magnitude and direction at each point in space, as opposed to scalar which has magnitude only. Such a quantity may be represented geometrically by an arrow of length proportional to its ...

Water vapor content of the air. See absolute humidity, dew point, mixing ratio, relative humidity, specific humidity.

Precipitation composed of white or translucent ice crystals, chiefly in complex branched hexagonal forms.

A reversing thermometer which is encased in a strong glass outer shell that protects it against hydrostatic pressure. Compare to unprotected thermometer.