Downward scattered and reflected solar radiation, coming from the whole hemisphere with the exception of the solid angle of the sun's disc on a surface perpendicular to the axis of this cone.

The difference between the air temperature and the dew-point. Also called dew-point deficit, dew-point depression.

The level at which ice crystals and snowflakes melt as they descend through the atmosphere.

Same as mercury barometer.

A computed characteristic of a particular river basin, expressed as the time difference between the time-center of mass of rainfall and the time-center of mass of resulting runoff.

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 ...

pattern barometer-Mercurial barometer with a fixed scale and cistern and which therefore requires only one adjustment before each reading.

In meteorology, an area of low pressure; a low or trough.

The direction, with respect to true north, from which the wind is blowing. Distinguish from magnetic wind direction. In all standard upper-air and surface weather observations, it is true wind direction that is reported.

Apparatus consisting of (a) standard radiosonde and radiosonde ground equipment to obtain upper-air data on pressure, temperature, and humidity, and (b) a self-tracking radio direction-finder to provide the elevation and azimuth angles of the radiosonde s ...

A clock-driven instrument mounting which automatically and continuously points in the direction of the sun. It is used with a pyrheliometera,hen continuous direct solar radiation measurements are required.

Instrument for measuring the intensity of radiant energy. Its principle is based on the variation of electrical resistance, with the incoming radiation, of one or both the metallic strips which the instrument comprises.

A clay atmometer consisting of a hollow ceramic sphere through which evaporation occurs. Evaporation is measured by the loss of water from the reservoir which feeds the sphere.

The attenuation of light.

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

The scientific study of the waters of the earth, especially with relation to the effects of precipitation and evaporation upon the occurrence and character of water in streams, lakes, and on or below the land surface. In terms of the hydrologic cycle, the ...

A numbering system using a base number of 16 and including the ten decimal digits (0 to 9) along with six alpha digits (A to F). Thus. a digit is available to represent each of the possible values of a 4-bit binary digit.

A point (or line) on a scale used for reference or comparison purposes. In calibration of meteorological thermometers, for example, the fiducial points are 100

A measure of the amount of "spin" (or rotation) in the atmosphere.

Strong winds concentrated within a narrow band in the atmosphere. The jet stream often "steers" surface features such as front and low pressure systems.