Study reveals uneven land sinking across New Orleans, raising flood-risk concerns
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The study used a remote sensing technique called InSAR (Interferometric Synthetic Aperture Radar), which detects millimeter-scale changes in land surface elevation by comparing satellite radar images taken over time. This allowed the researchers to build the most detailed map yet of vertical land motion in New Orleans-including areas like wetlands that had previously lacked reliable data.
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Wetlands east of the city, long known for their ecological importance, are also sinking rapidly in places. In some spots, the loss of elevation could transform marshes into open water within a decade if trends continue. This has implications not just for wildlife but also for storm protection, as wetlands help buffer storm surges.
New Orleans, much of which lies below sea level, relies on an elaborate system of levees, pumps and drainage canals to keep water out. As sea levels rise and the ground sinks, the margin for error narrows.
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