A class of rain gauge in which the level of the collected rain water is measured by the position of a float resting on the surface of the water.

A reversing thermometer which is encased in a strong glass outer shell that protects it against hydrostatic pressure. Compare to unprotected thermometer.

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

Amount of water, expressed as a depth or as a mass, which would be obtained if all the water vapor in a specified column of the atmosphere were condensed and precipitated.

A standard unit of atmospheric pressure, defined as the pressure exerted by a 760 mm column of mercury at standard gravity (980.665 cm/sec2 ) at O

Solar radiation of selected wavelengths.

An absolute pyhrliometer, developed by C.G. Abbott, in which the radiation-sensing element is a blackened water-calorimeter.

A hygrometer using goldbeater's skin as the sensitive element. Variations of the physical dimensions of the skin caused by its hygroscopic character indicate relative humidity. (Note: Goldbeater's skin is the prepared outside membrane of the large intesti ...

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

A warm, dry wind on the lee side of a mountain range, the warmth and dryness due to adiabatic compression upon descent.

Readily taking up and retaining moisture.

A semiconductor which exhibits rapid and extremely large changes in resistance for relatively small changes in temperature.

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

Either of two colored luminous spots that appear at points 22

The ratio of the existing amount of water vapor in the air at a given temperature to the maximum amount that could exist at that temperature. Usually expressed in percent.

Instrument which measures and records the amount of evaporation over time.

A measure of the degree to which the weather or climate of a region is favorable to the process of evaporation. Usually considered to be the rate of evaporation. under existing atmospheric conditions, from a surface of water which is chemically pure and h ...

A large body of air having similar horizontal temperature and moisture characteristics.

An instrument for taking photographs of an image of the sun in monochromatic light.

A clock-driven device for recording the time of occurrence of an event or the time interval between the occurrence of events.