The Transition of High-Accuracy Satellite Altimetry from Research to Operational Agencies, or Continuity of the Jason Climate Record of Global Sea Level

Initiated by NASA and CNES (the French Space Agency) with the launch of the TOPEX/Poseidon high-accuracy satellite altimeter mission in 1992, the climate record of global sea level has been maintained by the successive NASA/CNES Jason-1 and Jason-2 missions. This climate record has demonstrated that global mean sea level is rising at a rate of ~3 mm/year, a rate approximately twice that estimated by the global tide gauge network during the previous century. Beginning with Jason-2, NASA and CNES - as a first step to the transition of high-accuracy altimetry from the research to operational agencies - invited NOAA and its European counterpart, EUMETSAT, to share in assuming the responsibility for the ground system, both the operation of the satellite and routine data processing. Then, beginning with new starts both in the U.S. and Europe for Jason-3 in FY2010 - 23 years after the new start for TOPEX/Poseidon and three satellites later - NOAA and EUMETSAT assumed responsibility for continuing the this climate record when they secured funding for Jason-3. To be launched in late 2013, Jason-3 is planned to overlap with Jason-2 during the last six months of the five-year design life of Jason-2, which in turn overlapped similarly with Jason-1, and it with TOPEX/Poseidon. Jason-3 is characterized as a clone of Jason-2, which is a clone of Jason-1. Beyond Jason-3, given that there will be no more Poseidon buses available, initial planning is underway for a Jason-CS (Continuing Series) that is proposed to utilize ESA's Cryosat bus. Jason-CS will constitute a two- or three-satellite series, and the first is being planned to overlap with the last year of the five-year design life for Jason-3. For the first satellite of the Jason-CS series, NOAA and EUMETSAT will be joined by ESA.