Coordination Funds

卫星重力测量提供了在全球范围内量化地球系统质量再分布的唯一机会。20年来的GRACE和GRACE-FO重力场模型展示了对各种地球动力学过程和气候相关科学的开创性见解。第一次，水文学家可以量化地下水的大规模损失，冰川学家可以确定格陵兰和南极洲冰盖的融化，海洋学家能够关闭海洋的质量和热量收支，仅举几个例子。然而，Grace和Grace-FO还没有满足科学和用户需求，这些需求已经在2014年由国际大地测量和地球物理联合会(IUGG)建立的多学科专家小组总结出来。因此，地球科学界需要不断提高时变重力场模型和相应质量传输产品的精度、空间和时间分辨率以及长期一致性。因此，研究组同时在第一阶段努力改进和更好地理解应用的传感器数据、背景模型和处理策略。这导致了三个测试年的重力场模型已经有了显著的改进。第二阶段的新工作将在这里连接。NEROGRAV再次按照六个单独的项目进行构建，这些项目旨在有效地实现研究小组的四个具体目标。其中三个不变的是地球物理背景模型的改进和误差量化、时空参数化的改进和独立数据的验证。在这里，第一阶段的结果被应用于整个时间序列，并将回答以前工作中出现的问题。第四个目标包括对未来重力场飞行任务的规划建议，并已扩大到包括质量运输时间序列的地球物理应用。NEROGRAV汇集了德国大学和非大学研究机构在卫星重力测量领域的关键研究小组的具体专门知识。所有小组都在大地测量数据获取和建模方面拥有长期的专门知识传统，并将从海洋学、水文学、固体地球、地球物理学以及大气和气候科学等不同邻近学科提供独特的补充专门知识。因此，预计第二个供资阶段不仅将在未来20年内创建显著改进的GRACE/GRACE-FO重力场模型，而且还将使基于这一长期系列的地球物理应用成为可能，例如量化北大西洋深水输送作为大西洋子午线翻转环流变化的指标、评估水文气象极端事件或确定陆地水储量变化中的气候特征。

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.