Living Planet

Parameter Choice Strategies for Multiscale GOCE Modeling

Martin Gutting⁽¹⁾, Martin Fengler⁽¹⁾ , Willi Freeden⁽¹⁾ , and Sergei Pereverzev⁽²⁾

⁽¹⁾ Geomathematics Group Kaiserslautern, K-Tech, P.O. Box 3049, 67653 Kaiserslautern, Germany
⁽²⁾ K-Tech, P.O. Box 3049, 67653 Kaiserslautern, Germany

Abstract

The determination of the Earth's gravitational field from GOCE measurements is a exponentially ill-posed problem which requires adequate methods of regularization. Multiscale Tikhonov regularization, i.e. Tikhonov scaling functions and wavelets, has been suggested as a means for the solution of the SGG-Problem e.g. by Freeden (1999). It has already been successfully applied for CHAMP modeling by M. Fengler, W. Freeden and J. Kusche (2003). However, the main question in Tikhonov regularization is the choice of a suitable regularization parameter. Our intention is to present some different numerical tests for known methods for the choice of this parameter (such as L-curves, generalized cross validation) to simulated GOCE data. Moreover, we introduce techniques that have not yet been applied in GOCE modeling: quasi-optimality criterion and GOCE specific strategies from Freeden, Pereverzev (2000). All these different approaches are compared within a multiscale concept that allows not only global, but also local modeling of GOCE data.

Keywords: ESA European Space Agency - Agence spatiale europeenne, observation de la terre, earth observation, satellite remote sensing, teledetection, geophysique, altimetrie, radar, chimique atmospherique, geophysics, altimetry, radar, atmospheric chemistry

GOCE04