The sum of solar and terrestrial radiation.

The difference between the input quantity applied to a measuring instrument and the output quantity indicated by the instrument. The inaccuracy of an instrument is equal to the sum of its instrument error and its uncertainty.

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

See ceilometer.

The temperature registered by a thermometer with its bulb at the level of the tops of the grass blades in short turf.

Wind with a speed between 56 and 63 knots (64 and 72 mph); Beaufort scale number 11.

A modification of the dew cell used in radiosonde equipment.

Negative Vorticity Advection.

A hydrometeor consisting of a visible aggregate of minute water droplets suspended in the atmosphere near the earth's surface. Fog differs from cloud only in that the base of fog is at the earth's surface while clouds are above the surface.

The total area drained by a river and its tributaries. Same as watershed.

A standard unit of atmospheric pressure, defined as the pressure exerted by a 760 mm column of mercury at standard gravity (980.665 cm/sec2 ) at O

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 ...

The elevation of the water surface in a stream as measured by a river gauge with reference to some arbitrarily selected zero datum.

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 ...

An Instrument used to determine dew point.

A protocol similar to RS232 which permits data interchange on multidrop networks of up to 32 nodes using a single twisted pair cable. In order for this protocol to be used, each device on a network must have some level of intelligence in order establish o ...

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.

The size of the area comprising a watershed or river basin. Also called catchment area.

A nephoscope in which the motion of the cloud is observed by its reflection in a mirror.

Same as fogbow.