BPSGGOS Committee on

Contribution to Earth System Modelling

Chair: Maik Thomas (GFZ, Germany)


The GGOS Committee on “Earth System Modeling” tends to promote the development of physically consistent modular Earth system modeling tools that are simultaneously applicable to all geodetic parameter types (i.e., Earth rotation, gravity field and surface geometry) and observation techniques. Hereby, the committee contributes to:

  • The interpretation of geodetic monitoring data and, thus, to a deeper understanding of processes responsible for the observed variations;
  • The establishment of a link between the geodetic products delivered by GGOS and numerical process models;
  • A consistent combination and integration of observed geodetic parameters derived from various monitoring systems and techniques;
  • The utilization of geodetic products for the interdisciplinary scientific community.

Simulated mass anomalies in a modular system model approach.


The long-term goal is the development of a physically consistent modular numerical Earth system model for homogeneous processing, interpretation and prediction of geodetic parameters with interfaces allowing the introduction of constraints provided by geodetic time series of global surface processes, rotation parameters and gravity variations. This ultimate goal implicates the following objectives:

  • Development of Earth system model components considering interactions and relationships between surface deformation, Earth rotation and gravity field variations as well as interactions and physical fluxes between relevant compartments of the Earth system;
  • Promotion of homogeneous processing of geodetic monitoring data (de-aliasing, reduction) by process modeling to improve analyses of geodetic parameter sets;
  • Contributions to the interpretation of geodetic parameters derived from different observation techniques by developing strategies to separate underlying physical processes;
  • Contributions to the integration of geodetic observations based on different techniques in order to promote validation and consistency tests of various geodetic products.


Current activities focus on:

  • Implementation of interfaces to geodetic monitoring data based on Kalman and particle filter approaches in order to constrain and improve stand-alone model approaches and to prove consistency of various geodetic monitoring products;
  • Implementation and evaluation of various numerical approaches with different complexities for the consideration of self-attraction and loading in ocean general circulation models;
  • Combination of neural network modules with stand-alone models as a basis for further studies on the applicability of artificial intelligence for downscaling purposes.
  • Feasibility studies for the provision of error and uncertainty estimates of model predictions of geodetic parameters (Earth rotation, gravity field, surface deformation) due to imperfect model physics, initialization, and external forcing.

Selected Publications

• Boergens, E., Dobslaw, H., Dill, R., Thomas, M., Dahle, C., Flechtner, F.: Modelling spatial covariances for terrestrial water storage variations verified with synthetic GRACE-FO data. GEM – International Journal on Geomathematics, 11, 24, 2020.
• Dobslaw, H., Bergmann, I., Dill, R., Forootan, E., Klemann, V., Kusche, J., Sasgen, I.: The updated ESA Earth System Model for future gravity mission simulation studies. Journal of Geodesy, 89, 5, p. 505-513, 2015.
• Irrgang, C., Dill, R., Boergens, E., Saynisch-Wagner, J., Thomas, M.: Self-validating deep learning for recovering terrestrial water storage from gravity and altimetry measurements. Geophysical Research Letters, 47, 17, e2020GL089258, 2020.
• Konrad, H., Sasgen, I., Klemann, V., Thoma, M., Grosfeld, K., Martinec, Z.: Sensitivity of Grounding-Line Dynamics to Viscoelastic Deformation of the Solid-Earth in an Idealized Scenario. Polarforschung, 85, 2, p. 89-99, 2016.
• Martinec, Z., Klemann, V., van der Wal, W., Riva, R. E. M., Spada, G., Sun, Y., Melini, D., Kachuck, S. B., Barletta, V., Simon, K., James, T. S., G A.: A benchmark study of numerical implementations of the sea level equation in GIA modelling. Geophysical Journal International, 215, 1, pp. 389-414, 2018.
• Saynisch, J., Bergmann, I., Thomas, M.: Assimilation of GRACE-derived oceanic mass distributions with a global ocean circulation model. Journal of Geodesy, 89, 2, p. 121-139, 2015.

(last update 09.2020)