Since 2004 GFZ has been contributing to the Helmholtz research programme Atmosphere and Climate (ATMO) of the research field Earth and Environment, in close cooperation with the Karlsruhe Institute of Technology and the Forschungszentrum Jülich. Main objective of ATMO is to gain a better understanding of the role of the atmosphere in the climate system. For this purpose it examines key atmospheric processes by means of sophisticated measurements of atmospheric parameters, laboratory investigations, and numeric modeling.
The main focus of GFZ research in ATMO is the development and application of innovative atmospheric remote sensing techniques, which are based on the use of signals from the Global Navigation Satellite Systems (GNSS), as GPS, Galileo, GLONASS, Beidou or QZSS. For this purpose GFZ operates regional and global ground networks of GNSS stations and also dedicated GNSS receivers aboard Low-Earth-Orbiting (LEO) satellites (GRACE, TerraSAR-X, TanDEM-X, GNSS Radio Occultation). Atmospheric parameters, as water vapor or temperature can be derived from these measurements with high accuracy. One of the major advantages of the GNSS sounding techniques compared to other methods is the independency of cloudiness. The GNSS atmospheric data are operationally processed at GFZ and are used by the leading international weather centers to improve regional and global forecasts and are the base for climatological investigations.
The long-term and also very successful work of GFZ in this field is one of the reasons for the current acceptance of the GNSS based atmosphere sounding techniques as an established remote sensing technique with numerous scientific and operational applications. The most prominent example for this is the operational use of GNSS water vapor data at Germany and of globally distributed vertical temperature and water vapor profiles to improve global and regional weather forecasts.
Figure: Overview on GNSS based atmosphere-sounding techniques (click to open)