In a first, a space mission led by NASA and France tracked Earth’s rivers swelling and shrinking from month to month over the course of a year and found significantly less of a swing than previous model-based estimates. A record drought in the Amazon likely influenced the tally made by the Surface Water and Ocean Topography (SWOT) satellite. The findings also reveal new details about the underwater topography of the world’s river channels.
Launched in 2022, SWOT is a collaboration between NASA and the French space agency CNES (Centre National d’Études Spatiales). It’s the first satellite capable of surveying not only the ocean, but also nearly all the world’s lakes and rivers with ultraprecision. While SWOT does not measure the absolute volume of rivers, it can track their width, surface height and slope changing over time.
