A unit of energy equal to 101 ergs or to 0.2389 calories.

Difference between the temperatures of the dry-bulb and the wet-bulb thermometers of a psychrometer.

A measure of the intrinsic luminous intensity emitted by a source in a given direction. Luminance is a measure only of light. The comparable term for electromagnetic radiation in general is radiance.

An automatic, recording cloud height indicator.

The statement that the viscosity of air is independent of the density of air.

Same as balloon cover.

Graduated fixed stake used in regions of abundant snowfall to facilitate the measurement of snow depth.

A magnetometer of the electromagnetic type which is used to measure the horizontal intensity of the earth's magnetic field.

A mercury barometer in which the lower mercury surface is larger in area than the upper surface. The basic construction of a cistern barometer is as follows: A glass tube one meter in length, sealed at one end is filled with mercury, and then inverted. Th ...

In folklore, a name for rain.

Instrument for measuring the mean intensity of glo global solar radiation (direct and diffuse) near the earth's surface in a specified time interval.

American Standard Code for Information Interchange. A standard code used to represent data using 8 bits (7 data bits and I parity bit) per character.

Frequency Shift Keying. A form of frequency modulation of a data signal performed by a modem for transmission over dedicated wire or phone lines.

A recording anemometer.

Apparatus using the combined simultaneous action of a bimetallic thermometer and a hair hygrometer to move a needle in front of a divided scale. fts construction permits dew point variations to be indicated approximately.

Wind with a speed between 22 and 27 knots (25 and 31 mph); Beaufort scale number 6.

Same as instrument shelter.

The lowest value of a measured quality at which a sensor responds. Compare to tracking.

Hygrometer in which the dew (frost) point is determined by observing the temperature of an artificially cooled surface at the moment at which dew (frost) first appears on it.

To free something from the binding action of ice by warming it to a temperature above the melting point of ice. Also, a warm spell when ice and snow melt.