A Note on Temperature and Relative Humidity Corrections for Humidity Sensors

Abstract A widely used relative humidity (RH) sensor in atmospheric science is based upon a capacitive device that outputs voltage as a linear function of RH and then is corrected by an empirically determined polynomial expression, which is only a function of temperature. Based upon results of a dry bias in these measurements and upon a recent physical–mathematical model of how these devices may work, a new correction formula is derived, which is a function of temperature and RH. The new formula reproduces the old one near 40% RH and corrects the dry bias for RH values less than 40%.