Off the southwest tip of Iceland, you’ll find what’s often called a “marginal” body of water. This part of the Atlantic, the Irminger Sea, is one of the stormiest places in the northern hemisphere. On Google Maps it gets three stars: “very windy,” says one review. It’s also where something rather strange is happening. As the rest of the planet has warmed since the 20th century—less in the tropics, more near the poles—temperatures in this patch of ocean have hardly budged. In some years they’ve even cooled. If you get a thrill from spooky maps, check out one that compares the average temperatures