Parallelization and High Performance Computation for Accelerated CHAMP and GRACE Data Analysis

The work package WP210 “parallelization and high performance computing” of the Geotechnologien II project was aimed at improving the overall performance of the Earth Parameter and Orbit System (EPOS) software package used in gravity field processing at the Helmholtz Centre Potsdam GFZ German Research Center for Geosciences, and to interconnect various tasks in an optimal way. The two aspects of this optimization are, on the one hand, to minimize processing time, and, on the other, to solve for as many parameters as possible. In this chapter, we will focus our attention to three important sub-problems. First we show how processing can be simplified and, therefore, accelerated via a more convenient treatment of sender and receiver clock parameters, as they emerge in GPS processing. Secondly, an improved block-parallel algorithm for the computation of normal equations from observation equations, as they occur in gravity field adjustment, is presented. Thirdly, we show how it is possible to combine the existing software into a processing chain that admits the treatment of satellite arcs of arbitrary length in a consistent manner.