Updating the ESA Earth System Model for Future Gravity Mission Simulation Studies: ESA ESM 3.0

The ESA Earth System Model (ESA ESM; Dobslaw et al., 2015) is widely applied as a source model in end-to-end simulation studies for future gravity missions but has been also utilised to study novel gravity observing concepts on the ground. The model provides a synthetic time-variable global gravity field that includes realistic mass variations in the atmosphere, oceans, terrestrial water storage, continental ice sheets and the solid Earth for a variety of spatial and temporal frequencies. With the continuous development of the next gravity missions such as GRACE-C and NGGM / MAGIC, the ESM should provide a wide range of signals at spatial scales which might not have been reliably observed by currently active missions.

In this contribution, we present the first steps towards version 3.0 of the ESA ESM. The projected changes include an update of the atmosphere and ocean components, a small ensemble of co- and post-seismic earthquake signals, an updated GIA model, and additional mass balance signals from previously not considered Arctic glaciers. Extreme hydrometeorological events as well as climate-driven and anthropogenic impacts on continental water storage will be represented through an update of the hydrological component. Additionally, the ESM will separately include ocean bottom pressure variations along the western slope of the Atlantic, representing variations in the meridional overturning circulation. ESA ESM 3.0 will be available with 6 hourly resolution from January 2007 until December 2020. It will be also augmented with synthetic error time-series to facilitate stochastical modelling of residual background model errors.

Dobslaw, H., Bergmann-Wolf, I., Dill, R., Forootan, E., Klemann, V., Kusche, J., & Sasgen, I. (2015). The updated ESA Earth System Model for future gravity mission simulation studies. Journal of Geodesy, 89(5), 505–513. https://doi.org/10.1007/s00190-014-0787-8