IP3: High-Resolution Atmospheric-hydrological Background Modelling for GRACE/GRACE-FO – regional refinement and validation (HIRABAM-2)

PIs: Petra Friederichs, Jürgen Kusche (UBN)

Short description

For generating monthly level-2 data from GRACE and GRACE-FO, it is mandatory to remove sub-monthly non-tidal atmospheric and ocean mass variability during level-1 processing. We expect this to be pertinent to future missions (NGGMs). In this project, we focus on improving our understanding of atmospheric mass redistribution and the errors in atmospheric simulations. We investigate sub-monthly variability in the coupled atmospheric-terrestrial hydrological cycle, and we assess the potential of hydrology model simulations to improve the de-aliasing. This project has al-ready generated a consistent global data set of atmospheric-hydrological mass variation with improved spatio-temporal resolution over Europe, and it will continue to serve the RU through validation experiments. Finally, with a view on the current ~20 year data record that NGGMs will be able to extend to climate timescales, we suggest to shift the focus on the possibility of detecting hydrometeorological extremes and their statistics in a warming climate.

Research Objectives

  1. Improve methods for validation
  2. Address systematic and random errors in atmospheric background models, including small-scale processes
  3. Understand how hydro-meteorological extreme events map into L1/2 data
  4. Make recommendations to NGGM and climate community


  • Consistent atmospheric-hydrological simulations: towards coupled model evaluation
  • Observability of extreme hydro-meteorological events: Climate science