Enhanced near-real time gravity field retrieval for NGGM

The main goal of a next generation gravity mission (NGGM) is to improve the observation of mass transport processes primarily through an enhanced sampling with respect to space and time. Thus, high-resolution gravity products can be retrieved over short time periods which are highly valuable for geophysical applications like the monitoring and forecast of extreme climate events such as e.g. floods and droughts.

In this regard, a near-real-time (NRT) processing strategy was proposed in Purkhauser et al. (2020) where the so-called Wiese approach (co-parametrization of short-periodic low-resolution gravity fields and a long-period high-resolution one) was combined with a sliding window averaging. However, in recent studies some drawbacks of the Wiese scheme could be identified and partially rectified by a so-called data-driven multi-step self-de-aliasing approach (DMD).

In this contribution, the original NRT scheme is revised and re-run on the basis of the DMD method within numerical closed-loop simulations. The added value of DMD over the Wiese approach within the NRT processing is quantified and presented, and drawbacks and advantages of either methodology are discussed.