Designed to make the first-ever global survey of Earth's surface water, the Surface Water and Ocean Topography, or SWOT, satellite will collect detailed measurements of how water bodies on Earth change over time. The satellite will survey at least 90 percent of the globe, studying Earth's lakes, rivers, reservoirs and oceans at least twice every 21 days to improve ocean circulation models, and weather and climate predictions, and aid in freshwater management around the world.

One of 15 missions listed in the 2007 National Research Council Decadal Survey as missions that NASA should implement in the coming decade, SWOT will be jointly developed and managed by NASA, the French Space Agency (CNES), and the Canadian Space Agency.

Scientific Instruments

- Nadir altimeter
- KA-band radar interferometer