Particle on which the freezing of water occurs.

The total of all deviations of a transducer's output from a specified straight line in a constant environment.

Growth of a cloud or precipitation particle by the collision and union of a frozen particle with a super-cooled water drop.

See approximate absolute temperature scale, Celsius temperature scale, centigrade temperature scale, Fahrenheit temperature scale, Kelvin temperature scale, Rankine temperature scale, Reaumur temperature scale,

A line drawn through geographical points where a given seasonal biological event occurs on the same date.

Radiation with wavelengths greater than 4 microns. (In meteorology, same as infrared radiation.)

The portion of the strearnflow during any month or year derived from precipitation in previous months or years.

One of the radiation laws which states that the wavelength of maximum radiation intensity for a black body is inversely proportional to the absolute temperature of the radiating black body.

Operation mode of a communication circuit in which each end can transmit and receive, but not simultaneously.

A metallic element of atomic weight 200.6 1, unique (for metals) in that it remains liquid under all but very extreme temperatures.

A term used to describe a sensor (or sensors), the associated transducer(s), and the data readout or recording device.

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

A type of cloud height indicator which uses a searchlight to project vertically a narrow beam of light onto the cloud base. The height of the cloud is determined using a clinometer, located at a known distance from the ceiling light, to measure the angle ...

A refraction phenomenon similar to a parahelion, but occurring generally at a distance of 120

A wind scale adapted by the U.S. Forest Service for use in the forested areas of the northern Rocky Mountains (NRM). It is an adaptation of the Beaufort wind scale. The difference between these two scales lies in the specification of the visual effects of ...

An instrument which measures the intensity of radiation by determining the amount of chemical change( or fluorescence produced by that radiation.

Abbreviation for the pressure, temperature, and humidity data obtained by a radiosonde observation.

A instrument designed to study small fluctuations of some quantity. The microbarograph is an example of a recording pressure variometer.

A hygrometer in which the sensitive element is a strand or strands of human hair, the length of which is a function of the relative humidity of the air.

Same as aneroid barometer. Holostelic means wholly made of solids, while aneroid means devoid of liquid.