An Actual Space Laser Shows How Devastating Sea Level Rise May Be

This story was originally published by Wired and is reproduced here as part of the Climate Desk collaboration. An actual space laser is cruising 300 miles above your head right now. Launched in 2018, NASA's ICESat-2 satellite packs a lidar instrument, the same kind of technology that allows self-driving cars to see in three dimensions by spraying lasers around themselves as they roll down the street and analyzing the light that bounces back. But instead of mapping a road, ICESat-2 measures the elevation of Earth's surface with extreme accuracy. Although this space laser means you no harm, it does portend catastrophe. Today in the journal Nature Communications, scientists describe how they used ICESat-2's new lidar data to map the planet's land that's less than 2 meters above sea level, which makes it vulnerable to the creep of sea level rise.