Massentransporte und Massenverteilungen im System Erde  


Rigorous Fusion of Gravity Field into Stationary Ocean Models (RIFUGIO)


IGG-TG BonnWolf-Dieter Schuh

Silvia Becker

AWI BremerhavenMartin Losch

Grit Freiwald


In the project RIFUGIO we combine our so-called complete gravity field models (project In-

tErMod, first period of SPP 1257) with altimetric data for which a full error propagation is

implemented in the processing. Thus we derive estimates of the ocean’s mean dynamic topog-

raphy with a regular covariance matrix. The overall goal of this project is to integrate this

information into stationary ocean models and to assess the effects of this data combination on

improving ocean models. The study focuses on the North Atlantic Ocean bounded by the lati-

tudes 30◦ S and 80(66)◦ N.


We want to falsify the null hypothesis that the combined geoid and altimetric information is not accurate enough to improve ocean models. We test this null hypothesis by combining the newly obtained complete geoid model with altimetry and numerical ocean models with the help of inverse methods. The following questions are addressed:

  • How can geoid and altimetry information be combined with ocean models (ocean model error vs. geoid model error vs. altimetry error)?
  • Are the geoid covariances representative in the space domain and well calibrated?
  • Are ocean and geoid models consistent within their error estimates?
  • Does the additional geodetic information contribute to the ocean circulation estimate?
  • Does the inclusion of complete gravity field models reduce the estimated variances of selected target components in the ocean model (e.g., oceanic heat and volume transports)?


Becker, S., Schuh, W.-D., Losch, M., and Freiwald, G. (2.-6.5.2010). Estimating the mean dynamic sea topography by combinig so-called complete gravity field models and altimetry. Poster. EGU General Assembly 2010, Vienna.


Freiwald, G., Losch, M., Schuh, W.-D., and Becker, S. (2.-6.5.2010). Can we use current geoid models for improving ocean state estimation?. Poster. EGU General Assembly 2010, Vienna.