Large-scale mass redistribution in the oceans, 1993-2001

A recent study of satellite laser ranging measurements by Cox and Chao [2002] indicates that large-scale mass redistribution has caused a rapid change in Earth\textquoterights dynamic oblateness (J2) since 1998. Using satellite altimeter observations and two runs of an ocean general circulation models (OGCM), we examine mass variations in the oceans and their estimated effect on J2. Combined altimeter and OGCM results indicate variations similar to the J2 changes in 1998, and predict considerably larger oceanic effects on the J2 anomaly than purely OGCM estimates, suggesting that the oceans should not be ruled out by any means as a significant source of this interesting geodetic anomaly, until they have been studied further.