SWOT

SWOT, Surface Water and Ocean Topography, launched 16 December 2022, a NASA-CNES mission with Canadian and UK partners that maps water-surface height in two dimensions. Its KaRIn instrument is a Ka-band radar interferometer near 35.75 GHz with two antennas 10 m apart, measuring sea surface height across two 50 km swaths, 120 km total, at kilometer-scale resolution. That wide swath resolves submesoscale eddies and fronts the narrow nadir altimeters miss, and inland it inventories rivers and lakes. A nadir Jason-class altimeter fills the gap between swaths. SWOT extends altimetry from along-track profiles to true maps of the sea surface.