Researchers have already shown that on land and in the sea, plants and animals are shifting their ranges in response to rising global temperatures. Trees that thrive in warmer climates, for example, are spreading into areas where frigid winters once made survival impossible. And species that need cooler weather are retreating from areas that have become too warm.
For the fishing industry, such shifts are beginning to have practical consequences. In some cases, boats must travel farther to fishing grounds, driving up costs. Processing facilities have had to move, causing job losses in some communities. Valuable stocks have also shifted to waters controlled by other countries, sparking conflicts over who has the right to lucrative catches.
Species shift northward under both scenarios, but the shifts were greater with the 4°C rise. Along the Atlantic coast, for instance, the center of many species’ ranges shifted some 600 kilometers north, with tropical species moving into previously temperate waters and northern species abandoning the southern parts of their ranges. On the Pacific coast, some species shifted north by more than 1500 kilometers.