Dynamic Response of the Fine Wire Psychrometer for Direct Measurement of Water Vapor Flux

Abstract

For the measurement of humidity fluctuation in the atmospheric boundary layer, a wet- and dry-bulb ther-mocouple psychrometer has been used traditionally. However, in the direct measurement of water vapor flux with the eddy correlation method, errors are caused by its slow response to humidity fluctuations. The error in the water vapor flux measurement with psychrometer was studied on the dynamic response equation of wet- and dry-bulb thermometers. A new method of correction is presented for the scorer response of a fine wire psychrometer with variable time constants with fluctuating wind speed.