A particular pattern of snow sampler having an internal diameter of 1.485 inches so that each inch of water in the sample weighs one ounce.

Solar and terrestrial radiation directed downwards (towards the earth's surface); incoming radiation.

A fixed support for mounting maximum and minimum thermometers of the liquid-in-glass type. The support holds the thermometers at the correct operating attitude and also permits their rotation for resetting when desired.

Thermometer used for measuring the lowest temperature attained during a given interval of time, for example, a day.

That portion of the record of a microbarograph between any two (or a specified small number) of successive crossings of the average pressure level (in the same direction). Analogous to microseism.

For a given location, a measure of the long-range effectiveness of precipitation in promoting plant growth. Also called precipitation-evaporation index.

An instrument for measuring the frost point of the atmosphere.

A hygrometer which includes an arrangement for the time recording of atmospheric humidity.

Same as an upper air observation, but commonly used to refer to a single complete radiosonde observation.

Companion to the wet-bulb thermometer in a psychrometer. Used to measure ambient air temperature.

Thermodynamic change of state of a system in which there is transfer of heat across the boundaries of the system. Compare to adiabatic process.

A measure of luminous flux remaining in a light beam after it has passed through a specified distance of the atmosphere.

Thermometer in which the difference in the rates of expansion with temperature of a liquid and its receptacle is used as a measure of the temperature. The liquid used may be ethyl alcohol, toluene, petroleum, or mercury.

Same as Aeolian.

A direct-vision nephoscope constructed in the following manner: A grid-work of bars is mounted horizontally on the end of a vertical column and made free to rotate about the vertical axis. The observer rotates the grid and adjusts his or her position unti ...

A class of rain gauge in which the level of the collected rain water is measured by the position of a float resting on the surface of the water.

A c.g.s. (centimeter-gram-second) unit of mass. Originally defined as the mass of 1 cubic centimeter of water at 4

Force wind-Wind with a speed above 64 knots (73 mph); Beaufort scale numbers 12 through 17.

Same as atmometer.

Wind with a speed between 17 and 21 knots (19 and 24 mph); Beaufort scale number 5.