Evolution and Accuracy of Surface Humidity Reports

摘要: AbstractUntil recently surface humidity was predominantly measured using psychrometers (wet- and dry-bulb thermometers). In some countries, often in conjunction with increased automation, the measurement technique has changed—usually to capacitive sensors. The scale of change instrumentation error characteristics operational instruments have not been well documented. This paper provides an overview these their characteristics, intended be useful for climate forecast users data. It also includes detailed results from comparisons sensors a chilled mirror reference instrument at site United Kingdom under (near) conditions. performed near saturation but underread lower humidities; any large errors tended positive because insufficient water supply wet bulb. New perform they usually drift higher values during d...