Challenges in Deriving Trends from GRACE
The following contribution addresses some of the problems involved with the determination of long-term gravity field variations from GRACE satellite observations. First of all the choice of the time span plays a very important role, especially since it generally is a hard task to derive secular trends from only a few years of satellite data. Another issue, when one is interested in a single trend phenomenon, is the reduction of all other geophysical effects causing long-term gravity field variations. This paper uses the example of trends in continental hydrological water masses for the case of the High Plains aquifer to demonstrate some of the challenges implicated by trend analysis from GRACE.
KeywordsGravity Field Geoid Height Glacial Isostatic Adjustment Spherical Harmonic Coefficient Pole Tide
The authors would like to thank Volker Klemann from the GFZ for providing the GIA model. The support by the DFG (Deutsche Forschungsgemeinschaft) within the frame of the special priority program SPP1257 “Mass transport and mass distribution in the Earth system” is gratefully acknowledged.
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