Only seven months after NASA’s Oceans Melting Greenland (OMG) mission wrapped its last field campaign on the world’s largest island, an OMG crew is back in Greenland to collect more data. With two or three field projects a year since 2016, no wonder OMG has made the most comprehensive measurements yet of how ocean water lapping at the undersides of Greenland’s melting glaciers affects them. All that data has answered a lot of existing questions—and it’s raised plenty of new ones.