Aliased ocean tide signal in submonthly gravity field products and implications for NGGM/MAGIC

The S2 tidal aliasing is a known issue and demands special attention when working with monthly mass variation data from GRACE and GRACE Follow-On. As the temporal resolution of the gravity field time series improves, the likelihood of tidal aliasing also increases, provided that the amplitude of these signals is significant. The period at which aliasing occurs depends on the specific frequency of the ocean tide component and the sampling characteristics of the satellites. In this contribution, we compute the aliasing periods for a set of less-studied ocean tide constituents for which, to a certain extent, no ocean tide solutions exist. We compute equivalent water height maps for the daily solutions from TU Graz, daily swath mascon solutions over the oceans from CSR, and the 10-day solutions from CNES/GRGS. Subsequently, we conduct a harmonic analysis to uncover aliased ocean tide signals in these alternative submonthly gravity field models, and discuss implications of ocean tide model errors for NGGM/MAGIC.