Ocean Sci. Discuss., 9, 2187-2214, 2012
© Author(s) 2012. This work is distributed
under the Creative Commons Attribution 3.0 License.
Review Status
This discussion paper has been under review for the journal Ocean Science (OS). Please refer to the corresponding final paper in OS.
Evaluation of Release-05 GRACE time-variable gravity coefficients over the Ocean
D. P. Chambers and J. A. Bonin
College of Marine Science, University of South Florida, St. Petersburg, FL, USA

Abstract. The latest release of GRACE gravity field coefficients (Release-05, or RL05) are evaluated for ocean applications. Data have been processed using the current methodology for Release-04 (RL04) coefficients, and have been compared to output from two different ocean models. Results indicate that RL05 data from the three Science Data Centers – the Center for Space Research (CSR), GeoForschungsZentrum (GFZ), and Jet Propulsion Laboratory (JPL) – are more consistent than the previous RL04 data. Moreover, the variance of residuals with the output of an ocean model is 50–60% lower for RL05 data than for RL04 data. A more optimized destriping algorithm is also tested, which improves the results slightly. By comparing the GRACE maps with two different ocean models, we can better estimate the uncertainty in the RL05 maps. We find the standard error to be about 1 cm (equivalent water thickness) in the low- and mid-latitudes, and between 1.5 and 2 cm in the polar and sub-polar oceans, which is comparable to estimated uncertainty for the output from the ocean models.

Citation: Chambers, D. P. and Bonin, J. A.: Evaluation of Release-05 GRACE time-variable gravity coefficients over the Ocean, Ocean Sci. Discuss., 9, 2187-2214, doi:10.5194/osd-9-2187-2012, 2012.
Search OSD
Discussion Paper
    Final Revised Paper