The results were published in the journal Science and presented on Thursday to the American Association for the Advancement of Science annual meeting. Previous studies of human impacts have focused on a single activity or isolated ecosystem, and rarely on a global scale.
Scientists found that almost no areas have been left pristine and that more than 40% of the world’s oceans have been heavily affected. Human impact is most severe in the North Sea, the South and East China Seas, the Caribbean, the Mediterranean, the Red Sea, the Gulf, the Bering Sea, along the eastern coast of North America and in much of the western Pacific.
Research team leader Ben Halpern, of the University of California, Santa Barbara, said that when summed up by the study, human impact "looks much worse than I imagine most people expected".