Abbreviation for radio frequency.

The outer, solid portion of the earth: the crust of the earth.

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

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

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

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

Same as Aeolian.

Overflowing by water of the normal confines of a stream or other body of water, or accumulation of water by drainage over areas which are not normally submerged.

Of or pertaining to rain.

A feeble oscillatory disturbance of the earth's crust, detectable only by very sensitive seismographs. Certain types of microseisms seem to be closely correlated with pressure disturbances. See microbarm.

The change in barometric pressure within a specified period of time (typically 3 hours for meteorological observations).

A hygrometer based upon the diffusion of water vapor through a porous membrane.

A unit of luminous flux. The lumen is equal to the luminous flux radiated into a unit solid angle (steradian) from a small source having a luminous intensity of one candle. An ideal source possessing an intensity of one candle in every direction would rad ...

A hydrometeor consisting of an aggregate of microscopic and more-or-less hygroscopic water droplets suspended in the atmosphere. It reduces visibility to a lesser extent than fog. The relative humidity of mist is often less than 95 percent.

The process by which water in plants is transferred as water vapor to the atmosphere. Also, the amount of water so transferred.

A strong wind characterized by a sudden onset, a duration on the order of minutes, and a rather sudden decrease in speed.

Programmable Read-Only Memory. Read-only memory which can be programmed by the user using a special hardware programmer.

Name sometimes used in place of pyranometer as a generic term.

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

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.