Water condensed onto objects at or near the ground, due to the fact that their temperatures have fallen below the dew point temperature of the surrounding air, but not below freezing.

A cover which fits over a large inflated balloon to facilitate handling in high or gusty winds.

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.

An instrument which measures the instantaneous rate at which rain is falling on a given surface. Also called a rate-of-rainfall gauge.

A fabric cone attached to a metal ring and used to indicate wind direction. often at airfields.

A photometer that measures the received intensity of a distance tight source.

Same as fogbow.

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.

An instrument for measuring the relative speed of a fluid. It consists of a concentric pipe arrangement in which the inner pipe is open at one end and the outer pipe is perforated and closed at both ends. Each pipe is connected to a manometer. The unit is ...

The correction applied to an instrument to account for the effect of temperature upon its response characteristics.

Apparatus from which the nature and time of precipitation may be determined.

Balance of the water resources of a region, comparing precipitation and inflow with outflow, evaporation, and accumulation.

A systematic summary of the terms (inflow, outflow, and storage) of the storage equation as applied to the computation of soil-moisture changes, ground-water changes, etc. An evaluation of the hydrologic balance of an area. Also called basin accounting, w ...

A type of anemometer in which the rotation of an element serves to measure the wind. Rotation anemometers are divided into two classes; those in which the axis of rotation is horizontal, such as the windmill anemometer, and those in which the axis of rota ...

A photometric unit of illuminance or illumination equal to one lumen per square centimeter.

General term for an instrument used to make direct measurements of visual range or measurements of the physical characteristics of the atmosphere which determine the visible range.

The frequency of a carrier wave.

Same as constant-level balloon.

The boundary between the troposphere and stratosphere, usually characterized by an abrupt change in lapse rate. Its height varies from 10 to 20 km. Regions above the tropopause have greater atmospheric stability than regions below.

A set of electrical conductors, often on a backplane, that carry data and power signals among the various components of a computer.