“Unlocking the Future: 5 Insights on SWOT Analysis and Global Water Challenges”

The global Surface Water and Ocean Topography mission will deliver high-resolution information regarding the salt and freshwater on Earth’s surface.

On December 12, NASA will send the Surface Water and Ocean Topography (SWOT) satellite into Earth’s orbit from Vandenberg Space Force Base in California aboard a Falcon 9 rocket. The initiative is a joint enterprise between NASA and the French space agency Centre National d’Études Spatiales (CNES), with support from the Canadian Space Agency (CSA) and the UK Space Agency, focused on examining water across more than 90% of the planet’s surface.

This satellite will assess the elevation of water in Earth’s freshwater sources and oceans, supplying valuable insights regarding the ocean’s impact on climate change; how a warming planet affects lakes, rivers, and reservoirs; and how communities can enhance their preparation for disasters like floods.

Below are five ways in which SWOT will transform our understanding of water on Earth:

Water is crucial for sustaining life on our planet. Additionally, it serves a vital function in storing and transferring much of the excess heat and carbon trapped within the Earth’s atmosphere due to greenhouse gas emissions. It also affects our weather and climate. SWOT will assist scientists in monitoring Earth’s water budget – where water resides currently, where it originates, and where it is headed in the future. Understanding how water resources are evolving, the implications of those changes on local ecosystems, and how the ocean responds to and impacts climate change is essential.

The spacecraft’s scientific instruments will observe the world’s freshwater bodies and oceans with unprecedented precision. SWOT will gather information on oceanic features smaller than 60 miles (100 kilometers) across, aiding in the enhancement of researchers’ comprehension of the ocean’s function in climate change. Earth’s oceans have absorbed more than 90% of the additional heat trapped in the atmosphere due to human-driven greenhouse gas emissions. Scientists believe that transient ocean features, such as fronts and eddies, capture much of that heat – along with the extra carbon responsible for it.

By delivering a high-resolution perspective of freshwater bodies, SWOT will contribute to creating a much more comprehensive representation of Earth’s water budget. Numerous major rivers continue to pose a challenge for researchers, who are unable to equip them with monitoring devices for various reasons, including difficult accessibility. The spacecraft’s instruments will monitor virtually all rivers exceeding 330 feet (100 meters) in width, viewing them in three dimensions for the first time. Similarly, where ground and satellite technologies currently yield information about only a few thousand of the world’s largest lakes, SWOT will amplify that number to over one million lakes larger than 15 acres (62,500 square meters).

An essential aspect of forecasting our future climate is determining when the ocean will reduce its absorption of excess heat trapped in the atmosphere and begin releasing it back into the atmosphere, which could expedite global warming. SWOT will provide vital information concerning this global ocean-atmosphere heat interchange, allowing scientists to assess and advance climate predictions. Furthermore, the satellite will assist in bridging gaps in researchers’ understanding of sea level changes along coastlines, offering insights that can subsequently be used to refine computer models for sea level rise estimates and coastal flood forecasts.

Climate change is also accelerating Earth’s water cycle, resulting in more erratic precipitation patterns, including intense downpours and severe droughts. Consequently, some communities across the globe will experience flooding while others endure droughts. SWOT data will be utilized to monitor drought conditions in lakes and enhance flood predictions for rivers, supplying crucial information to water management agencies, disaster preparedness organizations, academic institutions, civil engineers, and others requiring water tracking in their regions.

With its groundbreaking technology and commitment to involving a diverse array of individuals who plan to utilize the mission’s data, SWOT is pioneering a course for future Earth-observing initiatives. Measurements from SWOT – along with the tools to support researchers in analyzing the data – will be available free of charge and accessible. This will facilitate research and application efforts by a wide range of users, including those who may not typically have access to such knowledge.

This ambitious mission is feasible due to a decades-long collaboration between NASA and CNES that began in the 1980s with the goal of monitoring Earth’s ocean. This partnership pioneered the implementation of a satellite-based instrument known as an altimeter to investigate sea levels, initiated with the launch of the TOPEX/Poseidon satellite in 1992. The NASA-CNES alliance has remained uninterrupted for three decades and has expanded to include collaboration with other agencies, such as the CSA and the UK Space Agency for SWOT, as well as ESA (European Space Agency), the European Organisation for the Exploitation of Meteorological Satellites, and the European Commission for the Sentinel-6 Michael Freilich satellite, which was launched in November 2020.

SWOT is collaboratively being developed by NASA and CNES, with contributions from the CSA and the UK Space Agency. JPL, managed for NASA by Caltech in Pasadena, California, heads the U.S. segment of the project. For the flight system payload, NASA supplies the Ka-band Radar Interferometer (KaRIn) instrument, a GPS scientific receiver, a laser retroreflector, a two-beam microwave radiometer, and NASA instrument operations. CNES contributes the Doppler Orbitography and Radioposition Integrated by Satellite (DORIS) system, the dual frequency Poseidon altimeter (developed by Thales Alenia Space), the KaRIn radio-frequency subsystem (in collaboration with Thales Alenia Space and with support from the UK Space Agency), as well as the satellite platform and ground control segment. CSA supplies the KaRIn high-power transmitter assembly. NASA is responsible for the launch vehicle and associated launch services.

For additional details regarding SWOT, please visit:

Jane J. Lee / Andrew Wang
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-0307 / 626-379-6874
jane.j.lee@jpl.nasa.gov / andrew.wang@jpl.nasa.gov

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