Surface mass redistribution from joint inversion of GPS site displacements, ocean bottom pressure (OBP) models, and GRACE global gravity models (JIGOG)

GPS 站点位移、海底压力 (OBP) 模型和 GRACE 全球重力模型 (JIGOG) 联合反演的表面质量重新分布

• 批准号: 30060709
• 负责人: Professor Dr.-Ing. Reinhard Dietrich
• 金额: --
• 依托单位: Alfred-Wegener-Institut (AWI) Helmholtz-Zentrum für Polar- und Meeresforschung
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/30060709?language=en
• 关键词: Surface; mass; redistribution; joint; inversion

In a collaborative effort between TUD-DEOS, AWI and GFZ, we aim at developing a strategy for the joint inversion of time series of GPS site displacements, ocean bottom pressure (OBP) data, and standard and non-standard, short-time GRACE gravity models, into mass transfers. Whereas geoid changes are linked to mass redistributions both directly and indirectly, GPS site displacements respond to mass flux indirectly through loading of the Earth.Previous research has indicated that, when combining monthly GRACE solutions with GPS, GPS could significantly contribute to spherical harmonics of global mass redistribution of up to degree 5, including degree 1. GPS sites are sparse for ocean areas and heterogeneous for continental areas. A joint inversion, accounting for error variance-covariance, site distribution and the individual sensitivities of GPS and GRACE in combination with OBP information, will provide more reliable results on all spatial scales than just combining degree-1 from GPS and higher degrees from GRACE. We plan to optimize the inverse methodology developed by Kusche and Schrama (2005a,b), to develop a complementary regional methodology, to incorporate bottom pressure from numerical ocean models, investigate consistency aspects, and validate results. Because relevant mass variations take place at sub-monthly scales GFZ will additionally contribute with nonstandard short-time (7-10 days) GRACE and GRACE/SLR combined gravity field solutions. A major application will be the determination of variations of the total ocean mass. In conjunction with measured oceanic volume variations we will be able to determine thermal expansion and thus global ocean warming with a much higher accuracy than conventional estimates can provide.

在TUD-DEOS，AWI和GFZ之间的合作努力中，我们旨在制定GPS站点位移时间序列的联合反转策略，海洋底部压力（OBP）数据以及标准和非标准，短时的宽限期重力模型，将其转化为大众转移。尽管地质变化与直接和间接的大规模再分配有关，而GPS站点的位置通过负载通过负载来响应质量通量。预览的研究表明，当将每月的宽限期解决方案与GPS结合在一起时，GPS可以显着对全球质量的质量造成的全球质量为5级，包括级别的水平，包括级别的一流。联合反转，即误差方差 - 协方差，场地分布以及GPS和GRACE与OBP信息结合使用的单个敏感性，将为所有空间尺度提供更可靠的结果，而不是仅仅结合GPS的gps和较高的恩典程度。我们计划优化Kusche和Schrama（2005a，b）开发的逆方法，以开发一种互补的区域方法，以纳入数值海洋模型的底压，研究一致性方面并验证结果。因为相关的质量变化是在次月尺度上进行的，GFZ将添加短期（7-10天）的宽限期和宽限期/SLR组合重力场解决方案。主要应用将是确定总海量的变化。结合测得的海洋体积变化，我们将能够确定热膨胀，从而以比常规估计值更高的精度来确定全球海洋变暖。