2025-03-19 NASA
＜関連情報＞
- https://www.nasa.gov/missions/swot/next-generation-water-satellite-maps-seafloor-from-space/
- https://www.science.org/doi/10.1126/science.ads4472
SWOTミッションによる深海の海洋テクトニクス Abyssal marine tectonics from the SWOT mission
Yao Yu, David T. Sandwell, and Gerald Dibarboure
Science Published:12 Dec 2024
DOI:https://doi.org/10.1126/science.ads4472
Editor’s summary
Detailed maps of the ocean floor come from ship crossings but can also be obtained using satellite altimetry. Yu et al. used radar altimetry observations from just 1 year of the Surface Water and Ocean Topography mission to develop a high-resolution global seafloor map (see the Perspective by Hwang and Yu). The new satellite observations have a resolution about twice that of the older observations, presenting an opportunity to better understand the geological features of the seafloor. —Brent Grocholski
Abstract
The global ocean covers 71% of Earth’s surface, yet the seafloor is poorly charted compared with land, the Moon, Mars, and Venus. Traditional ocean mapping uses ship-based soundings and nadir satellite radar altimetry—one limited in spatial coverage and the other in spatial resolution. The joint NASA–CNES (Centre National d’Etudes Spatiales) Surface Water and Ocean Topography (SWOT) mission uses phase-coherent, wide-swath radar altimetry to measure ocean surface heights at high precision. We show that 1 year of SWOT data offers more detailed information than 30 years of satellite nadir altimetry in marine gravity, enabling the detection of intricate seafloor structures at 8-kilometer spatial resolution. With the mission still ongoing, SWOT promises critical insights for bathymetric charting, tectonic plate reconstruction, underwater navigation, and deep ocean mixing.
