A system in which radar techniques are used to determine the range, elevation, and azimuth of a radar target carried a!oft by a radiosonde, so that wind data may be obtained along with the other meteorological data.

A line of equal or constant pressure.

The range through which the input may be varied without initiating a response. Usually expressed as a percentage of full-scale range.

An effect noted primarily in wet snow conditions when snow clings to the sides of a precipitation gauge and gradually accumulates until the gauge orifice is capped with accumulated snow. This effect can be minimized by using large collectors, and wind scr ...

Abbreviation for precipitation effectiveness index.

A warm, dry wind on the lee side of a mountain range, the warmth and dryness due to adiabatic compression upon descent.

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.

Occupational Safety and Health Administration. A regulatory office of the U.S. Department of Labor.

A power supply which achieves its output regulation by means of one or more active power handling devices which are alternately placed in the "off" or "on" states. It is more efficient than linear supplies which vary the conduction of power devices to ach ...

A self-recording thermometer.

The volume of water required to cover one acre to a depth of one foot: 43,560 cubic feet.

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 ...

In a system of moist air, the dimensionless ratio of the mass of water vapor to the total mass of the system.

A graphical aid used in fire weather forecasting to calculate the degree of forest-fire danger (or burning index). Commonly in the form of a circular slide rule, the firedanger meter relates numerical indices of (a) the seasonal stage of foliage, (b) the ...

The process by which one object becomes adhered to another by the binding action of ice.

A modification of the dew cell used in radiosonde equipment.

The condition of the atmosphere when the amount of water vapor present is the maximum possible at the existing temperature.

An atmometer consisting of a porous porcelain or ceramic container connected to a calibrated reservoir filled with distilled water. Evaporation is determined by the depletion of water in the reservoir.

The temperature at which all three phases of a substance can exist in equilibrium. This temperature occurs at only one pressure. The triple-point of water is 273.16 K and is the basis of the Kelvin scale.

A small balloon whose ascent is followed by a theodolite in order to obtain data for the computation of winds aloft.