TOPEX/POSEIDON and Jason – 25 years of high precision ocean altimetry

With the Jason high precision ocean altimetry mission continuing to be a success story in space, it is worth remembering that yesterday marked the 25th anniversary of its origin: The launch of TOPEX/POSEIDON.

Friday, 11 August 2017

News - 20170811-topex/poseidon

As the NASA/CNES Topex-Poseidon satellite ascended into orbit in 1992 it ushered in a new era of oceanography with the first highly accurate, global measurements of sea levels. That mission and its three successors, all named Jason, have continuously mapped global ocean currents and tides; opened our eyes to the global reach of El Niño and other climate events; created a quarter-century-long, extraordinarily precise record of global and regional sea level rise; and enabled improved forecasts of extreme weather events such as hurricanes, floods and droughts.

The successor for TOPEX/Poseidon, Jason-1, developed by NASA and CNES was launched in December 2001. Topex-Poseidon was eventually decommissioned in 2005 after 13 years in orbit. Jason-1 survived almost 12 years, until July 2013. Nine-year-old Jason-2 and Jason-3 (launched in January 2016) are still in operation.

EUMETSAT and High Precision Ocean Altimetry

EUMETSAT joined the Jason mission with Jason-2 when operations moved from the research agencies NASA and CNES to the U.S. National Oceanic and Atmospheric Administration (NOAA) and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT).

In October 2016, Jason-3 (launched in January 2016) took over the baton from Jason-2.

Jason-3 is the result of an international partnership between EUMETSAT, the French Space Agency (CNES), the US National Oceanic and Atmospheric Administration (NOAA), the US National Aeronautics and Space Administration (NASA), and the European Union, which funds European contributions to Jason-3 operations as part of the European Commission's Copernicus Programme.

Within Copernicus, Jason-3 is the reference mission for cross-calibrating Copernicus Sentinel-3 observations of sea surface height and the precursor to the future cooperative Sentinel-6/Jason-CS mission also implemented in partnership between Europe and the United States.

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