Coordination Funds

点击翻译按钮获取中文摘要

Satellite gravimetry provides the only opportunity to quantify mass redistribution in the Earth system on a global scale. The 20 years of monthly GRACE and GRACE-FO gravity field models revealed groundbreaking insights into a wide range of various geodynamic processes and climate related science. For the very first time hydrologists can quantify large scale loss of ground water, glaciologists can determine the melting of the Greenland and Antarctica ice sheets and oceanographers are able to close the mass and heat budget of the ocean, just to name a few.Nevertheless, GRACE and GRACE-FO do not fulfill the science and user needs yet which have been summarized in 2014 by a multi-disciplinary expert panel established under the auspices of the International Union of Geodesy and Geophysics (IUGG). As a consequence, the geoscientific community is in need to continuously improve the accuracy, spatial and temporal resolution and long-term consistency of time-variable gravity field models and corresponding mass transport products.Therefore, Research Group has concurrently worked in phase one towards improving and better understanding of applied sensor data, background models and processing strategies. This resulted in already significantly improved gravity field models for three test years.The new works in phase two will connect here. NEROGRAV is again structured along six Individual Projects which have been designed to efficiently reach four specific objectives of the Research Group. Three of them are unchanged the improvement and error quantification of geophysical background models, the improvement of spatio-temporal parameterization, and the validation against independent data. Here, the results of phase one are applied to the entire time series and questions arising from previous work will be answered. The fourth objective includes recommendations for planning of future gravity field missions and has been expanded to include geophysical applications of mass transport time series.NEROGRAV bundled the specific expertise of key research groups from Germany in the field of satellite gravimetry at universities and non-university research institutions. All groups have a long-term heritage of expertise in geodetic data acquisition and modeling and will additionally contribute their unique complementary expertise from various neighboring disciplines such as oceanography, hydrology, solid Earth, geophysics and atmospheric and climate sciences. Therefore, it is expected that the second funding phase will not only create significantly improved GRACE/GRACE-FO gravity field models over two decades, but also enable geophysical applications based on this long-term series such as quantifying North Atlantic deep water transports as indicator for variations in the Atlantic Meridional Overturning Circulation (AMOC), assessment of hydrometeorological extreme events or identification of climatic signatures in variations of the terrestrial water storage.