A photoelectric spectrophotometer which is used in the determination of the ozone content of the atmosphere.

Same as atmometer.

A thermometer with a muslin-covered bulb which is moistened. used to measure wet-bulb temperature.

A special type of radar target, usually a comer reflector, tied beneath a free balloon and designed to be an efficient reflector of radio energy.

Precipitation composed of white or translucent ice crystals, chiefly in complex branched hexagonal forms.

A unit of power equal to one joule per second or 10' ergs per second.

The upper surface of a column of liquid.

A rainbow seen in the spray of the ocean. It is optically the same phenomenon as the ordinary rainbow.

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

An instrument for the measurement of both solar and terrestrial radiation.

An instrument for measuring the extinction coefficient in water.

See calorie.

One of several constant-pressure levels in the atmosphere for which a complete evaluation of data derived from upper air observations is required.

The visibility along an identified runway, determined from a specified point on the runway with the observer facing in the same direction as a pilot using the runway. Compare to runway visible range.

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

A type of climatic diagram whose coordinates are some form of temperature vs. a form of humidity or precipitation.

For a given locality and month, an empirical expression devised for the purpose of classifying climates numerically on the basis of precipitation and evaporation.

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

In general, the transformation of data from a "raw" form to some useable form. In meteorology, this often refers to the conversion of the observed value of an element to the value which it would theoretically have at some selected or standard level. The m ...

An instrument which automatically determines the size distribution of raindrops.