Atmospheric De-Aliasing Revisited
In temporal gravity variations, the variations in the atmospheric mass distribution are one of the most prominent signals next to tides. Since they superimpose the desired signals in the case of the current satellite gravity missions GRACE and GOCE, they are considered noise and removed using models. Therefore, errors in these models directly propagate to the results of the missions and may lead to misinterpretations.
Considering this background we revisit the forward modelling of atmospheric mass variations in order to derive an optimal strategy for the de-aliasing for the GOCE mission. Starting from basic principles, the parametrization and especially the radial discretization are investigated using operational data from ECMWF. The impact of model updates is discussed in a case study. Finally, a comparison with data from NCEP is used to assess the uncertainty of the mass variations derived from atmospheric models.
KeywordsAtmospheric gravity forward modelling GOCE de-aliasing
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