General name for an instrument which measures the earth's magnetic field intensity.

In folklore, a name for wind.

Name given to the unit of pressure in the International System of Units (SI). Equal to 1 newton/meter2 or 0.01 millibar.

A series of Nansen-bottle water samples and associated temperature observations resulting from one release of a messenger.

A radiosonde whose carrier wave is modulated by audio-frequency signals whose frequency is controlled by the sensing elements of the instrument.

Electromagnetic radiation of shorter wavelength than visible radiation but longer than x-rays, between 0.02 and 0.4 micron (200 and 4000 angstrom).

See standard atmosphere.

A thermometer consisting of a clock mechanism the speed of which is a function of temperature.

Same as radiation pattern. Anticyclone-An area of high atmospheric pressure which has a closed circulation that is anticyclonic (clockwise in northern hemisphere and counterclockwise in southern hemisphere).

A system of physical units based on the use of the centimeter, gram. and the second as elementary quantities of length. mass. and time.

See radiosonde commutator.

An inert gas. A colorless, monatomic element which is found to occur in dry air to the extent of only 0.000524 percent by volume. Helium is very light, having a molecular weight of only 4.003 and specific gravity referred to air of 0.138. Because helium i ...

The total area drained by a river and its tributaries. Same as river basin.

The interval between the lower and upper measuring limits of an instrument, i.e. a thermometer with a range of -35 to 50

An old nautical term for mercury barometer.

The array of indicating marks and figure in relation to which the position of an index is observed, i.e. a scale plate on a recorder.

Conditions to which a device is subjected, not including the variable measured by the device. See normal operating conditions, reference operating conditions.

Same as instrument shelter.

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

The record of an aneroid barograph.