Accelerometer Parameterization and the Quality of Gravity Recovery and Climate Experiment Solutions

In preparation for the Center for Space Research Release 6 of Gravity Recovery and Climate Experiment (GRACE) data, 32 accelerometer parameterization schemes are analyzed, which combine skew-symmetric, symmetric, and full-scale matrices with four different bias parameterizations inspired on those used on Release 5. After three selection stages, it has been determined that the daily full-scale matrix parameterization combined with the daily bias and linear drift improved the quality of the degree 60 GRACE spherical harmonic solutions by reducing the amplitude of north-south elongated artifacts by nearly 1 mm geoid height in some months. The improvements are largest during the period of 2002-2005 and after 2011. From 2007 to 2010, this parameterization scheme slightly degrades the GRACE solutions (limited under 0.1 mm geoid height increase in the intensities of north-south artifacts), but it has been demonstrated that this effect is limited to small areas and is barely visually noticeable. As a result of the proposed parameterization scheme, throughout the complete GRACE data period, the discrepancy of the C-2,C-0 coefficient relative to satellite laser ranging data has been reduced by a factor of 2.