An atmospheric sounding instrument which is supported by a captive balloon and used to obtain temperature and humidity data from the ground level to a height of a few thousand feet. The data is telemetered to the ground through a wire cable.

Wind with a speed between 28 and 33 knots (32 and 38 mph); Beaufort scale number 7.

See radiation shield.

Frozen or partly frozen rain.

General term for any device that measures precipitation: principally a rain gauge or snow gauge.

Pertaining to the action or effect of the wind. Derived from the name of the Greek god of the winds, Aeolus.

Wind with a speed between 4 and 6 knots (4 and 7 mph), Beaufort scale number 2.

Root Mean Square. This notation is used frequently with error analysis. In that context, it is the square root of the arithmetic mean of the squares of the deviations of the individual calibration points from the theoretical or ideal response.

A form of psychrometer with wet-bulb and dry-bulb thermometers mounted on opposite sides of a specialty designed graph of the psychrometric tables. It is so arranged that the intersections of two curves determined by the wet-bulb and dry-bulb readings -yi ...

A liquid-in-glass thermometer which uses an organic substance such as alcohol as the thermometer liquid. This type of thermometer has a low freezing point and a high coefficient of expansion. It is less accurate, however, than a mercury thermometer.

Wind with a speed between 34 and 40 knots (39 and 46 mph); Beaufort scale number 8.

A type of disk hardness-gauge, especially useful in relatively soft snow. See disk hardness gauge.

A metallic element of atomic weight 200.6 1, unique (for metals) in that it remains liquid under all but very extreme temperatures.

Same as aneroid barometer. Holostelic means wholly made of solids, while aneroid means devoid of liquid.

A unit that represents one degree of deviation from a reference point in the mean daily outdoor temperature (usually 65

Solar and terrestrial radiation directed upward (away From the earth's surface); outgoing radiation.

The ratios, to the mean wind speed, of the average magnitudes of the component fluctuations of the wind along three mutually perpendicular axes.

A colorless and odorless gaseous element. The lightest and apparently the most abundant chemical element in the universe. However, it is found only in trace quantities in the observable portion of our atmosphere, only about 0.00005 percent by volume of dr ...

The boundary between the troposphere and stratosphere, usually characterized by an abrupt change in lapse rate. Its height varies from 10 to 20 km. Regions above the tropopause have greater atmospheric stability than regions below.

An atmospheric phenomenon, other than clouds, which obscures a portion of the sky from the point of observation. Also called obscuration.