Estimating Mean Sea Level Change from the TOPEX and Jason Altimeter Missions

TLDR

The Jason‑2 satellite altimeter mission, launched in June 2008, extended a precision sea‑level record that began with TOPEX/Poseidon in 1992 and continued with Jason‑1 in 2001. The authors combined data from TOPEX/Poseidon, Jason‑1, and Jason‑2, calibrating the record by comparing overlapping measurements during the tandem period and against independent tide gauge data to produce a seamless global mean sea‑level time series from 1993 onward. The assembled record shows an average sea‑level rise of 3.4 ± 0.4 mm yr⁻¹ from 1993 to 2009, with significant interannual variability driven by ENSO, including a reduced rise during the recent La Niña event.

Abstract

The Jason-2 satellite altimeter mission was launched in June 2008, extending the record of precision sea level measurements that was initiated with the launch of TOPEX/Poseidon in 1992 and continued with the launch of Jason-1 in December 2001. We have used the measurements from these three missions to construct a seamless record of global mean sea level change from 1993 to the present. We present the results of our calibration activities, including data comparisons during the "tandem period" of the missions, during which we solve for biases between the missions, as well as comparisons to independent tide gauge sea level measurements. When the entire record is assembled, the average rate of sea level rise from 1993–2009 is 3.4 ± 0.4 mm/year. There is considerable interannual variation due to ENSO-related processes, which include the period of lower sea level rise over the last three years of the time series during the recent La Nina event.