Abstract

The availability of Global Positioning System (GPS) radio signals has introduced a new promising remote sensing technique for the Earth’s atmosphere. GPS based radio occultation exploit GPS signals received onboard a Low Earth Orbiting (LEO) satellite for atmospheric limb sounding. Temperature an... Show moreThe availability of Global Positioning System (GPS) radio signals has introduced a new promising remote sensing technique for the Earth’s atmosphere. GPS based radio occultation exploit GPS signals received onboard a Low Earth Orbiting (LEO) satellite for atmospheric limb sounding. Temperature and water vapour profiles with high accuracy and vertical resolution can be derived from this measurements. The radio occultation experiment onboard the German CHAMP (CHAllenging Minisatellite Payload) satellite provided its first measurements in February 2001. Since that time up to 250 occultation measurements were performed per day. The successful operation demonstrated the immense potential of this technique for the global monitoring of stratospheric temperature, the tropopause region and the global humidity distribution in the troposphere. All of these are important variables of the climate system. In this presentation the GPS radio occultation experiment of CHAMP including the automatic data analysis at GeoForschungsZentrum (GFZ) Potsdam will be introduced Global tropopause parameters and stratospheric temperatures at selected pressure levels, derived from CHAMP measurements will be discussed. Attention is also given to CHAMP’s data product quality. Comparisons between atmospheric profiles with radiosonde data and meteorological analyses from the European Centre for MediumRange Weather Forecast (ECMWF) are presented. Show less