lar So Interferometer Antenna 1 10 m Baseline Interferometer Antenna 2 Nadir Altimeter 891 km ensured by the on going operation of Jason-2 [7], launched in 2008, and in the near future by Jason-3 planned to be launched at the end of July 2015. The historical NASACNES cooperation on Topex and Jason 1 was enlarged by including two operational agencies in the United States and Europe, NOAA (National Oceanic and Atmospheric Administration) and Eumetsat. The Jason satellites measure the sea-surface height with a 20km footprint and are extremely sensitive to sea-level variations, detecting differences as small as a centimeter. The ability to measure mean sea-level with such a high accuracy is a key asset for monitoring of the impact of climate change y a Arr Main Interf. Left Swath Main Interf. Right Swath Nadir Channels Nadir Altimeter Footprint H-Pol Interometer Swath V-Pol Inteferometer Swath 10-60 km 10-60 km Surface Water Topography Ocean Topography KNC Swath 5-15 km KNC Alt. KNC Swath 5-15 km Intrinsic Resolution From 2.5 m # 70 m to 2.5 m to 10 m Figure 5. SWOT imaging geometry. SSS SM August 2010 38 0.5 80 0.45 37 60 0.4 36 40 0.35 20 0.3 35 10 34 0.25 0.2 -20 0.15 33 -40 32 0.1 -60 0.05 -80 31 -150 -100 -50 0 50 100 150 0 Figure 6. Global map of soil moisture (SM m3 m-3) and ocean salinity (SSS g of salt per 1000 g of water) August 2010 (Ifremer-CATDS-Cesbio). 44 ieee Geoscience and remote sensing magazine june 2015