Acquisition of Aircraft-Based GPS Instrumentation for Atmospheric Remote Sensing Research

High resolution observations over data-sparse oceanic regions are critical if the trend towards higher resolution global numerical weather prediction (NWP) models is to be converted into tangible improvements in weather forecasting success. GPS radio occultation sounding of the atmosphere from airborne platforms has the potential to fill this unique niche in the global meteorological observing system. GPS radio occultation sensing of the atmosphere involves sub-horizontal line-of-sight measurements made at normal cruising altitudes as transmitting GPS satellites set or rise behind the horizon. A single 8 hour transatlantic flight could provide more than 22 vertical profiles of water vapor. The large number of humidity profiles, the frequent sampling, and the high vertical resolution in the range from the surface to 200 mbar are exactly the type of observations that are sorely needed, for example, as input for forecasting severe European storm systems that develop over the Atlantic Ocean, or for forecasting hurricanes developing over oceans off the coast of the U.S.