[{Image src='suenkel-hans-4.jpg' caption='' width='500' alt='Hans Sünkel' class='image_left'}]''__Gravity field determination from space__''\\ \\
[Hans Sünkel|User/Suenkel_Hans], Graz University of Technology, Austria\\ \\
__Abstract:__
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As an integral response to its mass distribution, the structure of the Earth’s gravitational field represents an important source of information about our planet. Its knowledge is therefore an indispensable for a substantial progress in the geosciences in general and in solid Earth physics, geodesy and oceanography in particular.
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For the first time in space geodesy, three dedicated gravity field missions are currently being realized. The three missions are based on different observation concepts and have one element in common: GPS-based high-low
satellite-to-satellite tracking (SST). A second dedicated on-board sensor makes the three missions focus on
different aspects of the Earth´s gravity field: the determination of the static field with utmost precision and resolution by gravity gradiometry (GOCE mission) versus the monitoring of the dynamic field with reduced
resolution (GRACE mission).
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The derived gravity field models, if combined with altimeter data, will allow the precise determination of the
absolute ocean circulation on a global scale, and substantially improve weather forecast and climate research.
Combined with seismic data, the knowledge of the global gravity field will enable a significant advance in the
understanding of the physics of the Earth’s interior and will contribute to a better understanding of processes such as plate tectonics, volcanism, and earthquake phenomena. And finally the knowledge of the global gravity field will provide a global height reference surface at the centimeter level which is of paramount importance for positioning and navigation.