Data-driven multi-step self-de-aliasing approach for GRACE and GRACE-FO data processing

SUMMARY Temporal aliasing errors resulting from the undersampling of non-tidal atmospheric as well oceanic mass variations constitute largest limitation towards retrieval monthly gravity solutions based on GRACE and GRACE-FO satellite missions. Their mitigation is thus a primary goal current research. Unfortunately, two-step co-parametrization approach proposed for application in Bender-type scenario Wiese et al. yields no added value single pair. A detailed study this parametrization strategy carried out it shown that reason flawed central assumption method, signals different spatial wavelengths can be perfectly captured separated with respect to their temporal extent. Based finding, we derive multi-step self-de-aliasing (DMD) which aims rectify shortcoming method specifically single-pair case while retaining its independence background-model-based de-aliasing atmosphere ocean (AO) signal components. The functionality novel validated within set numerical closed-loop simulations real data processing. simulation results show DMD may improve performance high-degree spectrum by more than one order magnitude if retrieve full AOHIS (i.e. atmosphere, ocean, hydrology, ice, solid earth) signal, at least factor 5 priori AO applied. Simultaneously, degrade low degrees, but also demonstrated issue mitigated introducing constraint into processing scheme. are widely confirmed obtained applying GRACE/GRACE-FO test years 2007, 2014 2019. applicability further retrieval. It double-pair-based equivalent method.