A photometer which measures the intensity of radiation as a function of the frequency (or wavelength) of the radiation.

Same as photometer.

A box-like structure designed to protect certain meteorological instruments from exposure to direct sunlight, precipitation, and condensation, while at the same time providing adequate ventilation. Instrument shelters are painted white, have louvered side ...

The general term for dry atmospheric suspensoids, including dust, haze, smoke. and sand. Compare to hydrometeor.

Air in motion relative to the surface of the earth. Almost exclusively used to denote the horizontal component.

Ice crystal deposits formed by sublimation (conversion of water vapor directly to ice) when temperature and dew point are below freezing.

A set of rules or conventions used to standardize data transfer between devices.

The cardinal points of the compass, i.e. north, south, east, west.

A pyrheliometer of the thermoelectric type. Radiation is allowed to fall on two concentric silver rings, the outer covered with magnesium oxide and the inner covered with lamp black. A system of thermocouples (thermopile) is used to measure the temperatur ...

An apparatus, used in studying soil temperatures, for measuring the total supply of heat during a given period.

Abbreviation for radio frequency.

The temperature at which all three phases of a substance can exist in equilibrium. This temperature occurs at only one pressure. The triple-point of water is 273.16 K and is the basis of the Kelvin scale.

A unit of heat originally defined as the amount of heat required to raise the temperature of water through one degree centigrade (the gram-calorie or small calorie), but this proved to be insufficiently precise. The 15

A temperature scale based on absolute zero. Same as Kelvin temperature scale.

Same as instrument shelter.

The lowest value of a measured quality at which a sensor responds. Compare to tracking.

An instrument used to measure the amount of dew formed on a given surface.

The rising of cold water from the deeper areas of the ocean to the surface. This phenomena often occurs along the California coast during the spring and summer.

A general term for instruments which sample atmospheric suspensoids by impaction. Same as impactometer.

A wind (or component thereof) directed down the slope of an incline and caused by greater air density near the slope than at the same levels some distance horizontally from the slope. Also called drainage wind and sometimes called katabatic wind.