NASA CNES SWOT: Surface Water and Ocean Mission Proceeds

SWOT will be able to measure the ocean's surface with 10 times the resolution of current technologies. 

This will allow scientists to study small-scale features that are key components of how heat and carbon are exchanged between the ocean and atmosphere.

NASA and the French space agency Centre National d'Etudes Spatiales (CNES) have agreed to jointly build, launch and operate a spacecraft to conduct the first-ever global survey of Earth's surface water and to map ocean surface height with unprecedented detail.

SWOT spacecraft concept: current design

NASA Administrator Charles Bolden and CNES President Jean-Yves Le Gall signed an agreement Friday at NASA Headquarters in Washington to move from feasibility studies to implementation of the Surface Water and Ocean Topography (SWOT) mission.

The two agencies began initial joint studies on the mission in 2009 and plan to complete preliminary design activities in 2016, with launch planned in 2020.

SWOT integrated measurement approach

"With this mission, NASA builds on a legacy of Earth science research and our strong relationship with CNES to develop new ways to observe and understand our changing climate and water resources," said NASA Administrator Charles Bolden.

"The knowledge we'll gain from SWOT will help decision makers better analyze, anticipate and act to influence events that will affect us and future generations."

SWOT is one of the NASA missions recommended in the National Research Council's 2007 decadal survey of Earth science priorities.

The satellite will survey 90 percent of the globe, studying Earth's lakes, rivers, reservoirs and ocean to aid in freshwater management around the world and improve ocean circulation models and weather and climate predictions.

This new agreement covers the entire life cycle of the mission, from spacecraft design and construction through launch, science operations and eventual decommissioning.

SWOT Flight system configurations

NASA will provide the SWOT payload module, the Ka-band Radar Interferometer (KaRIn) instrument, the Microwave Radiometer (MR) with its antenna, a laser retroreflector array (LRA), a GPS receiver payload, ground support and launch services.

NB: KaRIn is an updated version of Interferometric Synthetic Aperture Radar (InSAR) technique

SWOT measurement concept

CNES will provide the SWOT spacecraft bus, the KaRIn instrument's Radio Frequency Unit (RFU), the dual frequency Ku/C-band Nadir Altimeter, the Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) receiver package, satellite command and control, and data processing infrastructure.

For more information on the SWOT mission check out the NASA Presentation here (pdf) and the Science Requirements doc (pdf)