A reassessment of global and regional mean sea level trends from TOPEX and Jason-1 altimetry based on revised reference frame and orbits

Abstract

Mean sea level trends from TOPEX and Jason-1 altimeter data are recomputed using unified geophysical modeling and the new ITRF2005 terrestrial reference frame for the entire altimetric time series, with consistent orbits based on satellite laser ranging (SLR) and DORIS tracking data. We obtain a global rate of 3.36 ± 0.41 mm/yr over the 14 year period from 1993 to 2007. The regional sea level trends computed with the new reference frame show significant north/south hemispherical offsets of ±1.5 mm/yr relative to trends based on the previous 1995-era frame. Regional sea level trend comparisons for the time periods of 1993-1999 and 1999-2005 reveal strong basin-scale polarities and pronounced inter-decadal variability, with a relative increase in the global mean sea level trend of 1.5 ± 0.7 mm/yr in the latter seven years. Copyright 2007 by the American Geophysical Union.