Term: psychrometric hygrometer
https://doi.org/10.1351/goldbook.P04939

Definition:
Instrument by which the relative humidity of the atmosphere may be determined. It is generally composed of two temperature sensors, one of which measures the temperature of the air; the other sensor is moistened with water and senses the cooling due to evaporation of water. The temperature difference between the two sensors is a function of relative humidity; sometimes referred to as a 'wet-and-dry bulb' thermometer.

Related Terms:
1) relative humidity (http://doi.org/10.1351/goldbook.R05267).
2) evaporation (http://doi.org/10.1351/goldbook.E02227).

Source: PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2196 (https://doi.org/10.1351/pac199062112167)

Citation: 'psychrometric hygrometer' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.P04939

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