Measuring Atmospheric Stability with GPS

Abstract

Nowcasting of convective systems plays a crucial role in weather forecasting. The strength of convection depends on the (in)stability of the air column. The stability can be detected by radiosonde observations. However, these observations are not frequent (typically 2 times per day) and are expensive to deploy. In this article a method is presented to detect the stability of the atmosphere based on high-frequency global positioning system (GPS) path-delay observations. The convection parameter derived from these observations is the power of the nonisotropic GPS path-delay signal. Comparisons with the convective available potential energy obtained from radiosonde observations show a correlation with the convection parameter obtained from GPS. This result implies that, because of the continuous availability of GPS estimates and the good land coverage, this method of detecting atmospheric stability may be beneficial to forecasters.