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

Difference between the temperatures of the dry-bulb and the wet-bulb thermometers of a psychrometer.

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

See standard atmosphere.

See radiosonde commutator.

In folklore, a name for wind.

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

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.

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

The record of an aneroid barograph.

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

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

Same as instrument shelter.

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.

See feed.

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 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 statement that the viscosity of air is independent of the density of air.