NASA satellites document 'river tsunamis' pushing miles inland

: NASA's Jet Propulsion Laboratory, in collaboration with Virginia Tech researchers, has used satellite data to document 'river tsunamis,' also known as flow waves, in U.S. rivers. Three significant waves were identified: a 9.1-foot wave traveling in Montana’s Yellowstone River, a 30-foot wave in Texas's Colorado River, and a 20-foot wave in Georgia’s Ocmulgee River, with swathes ranging from 100 to 250 miles. The Satellite, called Surface Water and Ocean Topography (SWOT), uses microwaves to precisely measure the Earth's water surface height, providing critical insights for flood safety and environmental analysis. The method marks a significant advancement, promising better flood preparedness through enhanced real-time observation capability.

In a groundbreaking development, NASA's Surface Water and Ocean Topography (SWOT) satellite has captured large-scale flood waves—dubbed "river tsunamis"—traveling significant distances inland along U.S. rivers. These waves, ranging from 47 to 166 miles in length, were observed in states like Montana, Texas, and Georgia. Unlike ocean tsunamis driven by seismic activity, these riverine surges are primarily caused by extreme rainfall events or sudden releases from ice jams .

The SWOT mission, a collaboration between NASA and France's CNES, employs advanced radar interferometry to measure the height and extent of surface waters globally. This technology enables scientists to monitor dynamic changes in rivers, lakes, and reservoirs with unprecedented precision. By capturing the elevation profiles of these flood waves, researchers can better understand their formation, propagation, and potential impact on surrounding communities .

These river tsunamis pose significant hazards, especially in regions lacking robust flood control infrastructures like levees and floodgates. The ability to detect and analyze such events from space offers a valuable tool for hydrologists and emergency planners. It facilitates early warning systems and informs the design of mitigation strategies to protect vulnerable populations and infrastructure .

The observations also highlight the broader implications of climate variability and change. As extreme weather events become more frequent, understanding the behavior of inland flood waves becomes crucial. The data provided by SWOT contributes to a growing body of knowledge that can inform climate resilience efforts and water resource management practices .

In summary, the detection of these extensive riverine flood waves underscores the transformative potential of satellite technology in hydrological studies. By providing detailed, real-time data on inland water dynamics, missions like SWOT are essential in enhancing our preparedness for natural disasters and adapting to a changing climate .

Sources: NASA, Gizmodo