IP4: Near-real time, Long-term, LRI and SLR combination aspects (NELOS)

PIs: Natalia Panafidina (GFZ), Thomas Gruber (TUM) 

Short description

In the second phase of IP4 (now: NELOS) we focus on issues that are related to further optimization of the space-time parameterization, such as daily / near-real time (NRT), but also long-term parameterization, taking the results of phase 1 regarding stochastic modelling and treatment of background models into account. Special emphasis is also given to observations periods with bad data coverage or quality, in order to provide eventually an optimum long time series for climate research studies. Following the successful strategy applied in phase 1, we will first assess newly developed methods in a synthetic simulation environment, and will then apply the identified optimum approach to real data. Finally, we will investigate also new applications that are only enabled by the great performance of the GRACE-FO inter-satellite laser ranging, and combination aspects with SLR (Satellite Laser Ranging) in static and time-variable gravity field modelling. 

Research Objectives

  1. Derive daily/NRT gravity field models 
  2. Find optimal parametrization for “bad months” & develop co-parametrization methods for trend signals
  3. Derive a consistent 20+ years GRACE/-FO time series
  4. Investigate impact of LRI data for medium to high frequencies of the static gravity field


  • Method developments for daily/NRT and trend signal estimation
  • Consistent & improved monthly 20+ years time series 
  • Improved static combined gravity field model (e.g. in Polar areas)