Global gravity field models and their use in earth system research

The launch of dedicated gravity satellite missions such as CHAMP, GRACE and GOCE has revolutionized our knowledge of the Earth’s gravity field. Since the gravity field reflects mass distribution and mass transport through the complex system Earth, a precise knowledge of the global gravity field and its temporal variations is important for many areas of Earth system research, such as solid Earth geophysics, oceanography, hydrology, glaciology, atmospheric and climate research. In this paper the progress of global gravity field modelling based on satellite data is reviewed, with special emphasis on first results of the ESA mission GOCE, where the new observation type of satellite gradiometry enables to derive high-resolution static gravity field models. Additionally, first combined satellite-only gravity field models based on GRACE and GOCE, making benefit of the individual strengths of these two missions, are addressed, and the application of these gradually improving gravity field models in several fields of geoscientific research is discussed.