The OSTM/Jason-2 Mission

Abstract

The Ocean Surface Topography Mission/Jason-2 (OSTM/Jason-2) satellite altimetry mission was successfully launched on June 20, 2008, as a cooperative mission between CNES, EUMETSAT, NASA, and NOAA. OSTM/Jason-2 will continue to precisely measure the surface topography of the oceans and continental surface waters, following on the same orbit as its predecessors, TOPEX/Poseidon and Jason-1. To maintain the high-accuracy measurements, the mission carries a dual-frequency altimeter, a three-frequency microwave radiometer, and three precise positioning systems. The objectives of the mission are both operational and scientific. The mission will provide near-real time high-precision altimetric measurements for integration into ocean forecasting models and other products. The mission will also extend the precise surface topography time series started by TOPEX/Poseidon in 1992 over two decades in order to study long-term ocean variations such as mean sea level variations and interannual and decadal oscillations. The measurement system has been adapted to provide quality data nearer to the coasts, and over lakes and rivers. This paper provides an overview of the OSTM/Jason-2 mission in terms of the system design and a brief introduction to the science objectives.

Keywords:

• Satellite altimetry
• sea level
• operational oceanography

Acknowledgments

This article is dedicated to Yves Menard, who as CNES Project Scientist did so much to advance the Jason series of altimeters. Yves should have been the main author of this paper, and he is profoundly missed by all of us. The success of this mission is due to the enthusiastic and efficient participation of all engineers, scientists, program managers, and experts who have been involved in this project. In particular, we benefited greatly from the long-term cooperation set up between the Ocean Surface Topography Science Team, partly funded by CNES and NASA, and the project teams within the four agencies CNES, NASA, EUMETSAT, and NOAA. Finally we thank the reviewers for their useful comments and suggestions.