Comparing gps radio occultation observations with radiosonde measurements in the Australian region

GPS Radio Occultation (RO) is a robust space-based Earth observation technique, with the demonstrated potential for atmospheric profiling and meteorological applications. The GPS RO technique uses GPS receivers onboard Low Earth Orbit (LEO) satellites to measure the received radio signals from GPS satellites to obtain atmospheric profiles such as temperature, pressure, water vapour and electron concentration in the ionosphere using complicated atmospheric retrieval processes. The Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) was launched in April 2006. GPS RO data from this constellation of six LEO micro-satellites provides an observational data type for operational meteorology, providing significant information on the thermodynamic state of the atmosphere with the potential to improve atmospheric analyses and prognoses. Thus it is important to know and understand how COSMIC RO measurements compare to conventional atmospheric and meteorological sounding devices. In this study the COSMIC GPS RO temperature and pressure profiles are compared to those measured from radiosondes (Vaisala RS-92) in the Australian region.