Swot (Surface Water Ocean Topography) is planned to be launched in 2021 in a joint project including Nasa, Cnes, the Canadian Space Agency and the UK Space Agency. The goal is to join both land hydrology and oceanography communities in a single satellite. The technology for Swot is be a Ka-band Radar INterferometer (KaRIN, 0.86 cm wavelength).

During the 3-years of lifetime mission, the main goals are:

  • Provide sea surface heights (SSH) and terrestrial water heights over a 120 km wide swath with a +/-10 km gap at the nadir track.
  • Over the deep oceans, provide SSH within each swath with a posting every 1 km x 1 km
  • Over land, produce a water mask able to resolve 100 meter wide rivers and lakes of 250x250 m in size, wetlands, or reservoirs. Associated with this mask will be water level elevations with an accuracy of 10 cm and a slope accuracy of 1.7 cm/1 km (when averaging over water area >1 km²).
  • Cover at least 90 percent of the globe. Gaps are not to exceed 10 percent of Earth's surface.
Satellite  Swot
Launch on  16/09/2021
End Date 
Altitude  890 km
Inclination  77.6°
Repetitivity  1 21 days (1 day repeat cycle during CalVal phase)
Agency  Cnes/Nasa/CSA/UKSA