A UK-backed mission involving the University of Bristol, which will observe huge swathes of ocean and surface water in unprecedented detail, has launched into space. The international Surface Water and Ocean Topography (SWOT) satellite took off from Vandenberg in California on 16 December. SWOT will use a revolutionary radar instrument, named KaRIn, to survey at least 90% of the Earth’s surface, measuring and monitoring changes in the ocean, lakes, reservoirs, rivers and wetlands, to produce data that will help improve our understanding of climate change, as well as predict and mitigate flood risks around the world.