National Geographic : 2017 Apr
INDIAN OCEAN North Sea East China Sea ATLANTIC OCEAN PACIFIC OCEAN Hong Kong Dubai Istanbul Jakarta Singapore Surabaya Manila Colombo Tianjin Los Angeles Seattle New York Rio de Janeiro Charleston Tangier Dakar Cape Town Valencia Shanghai Rotterdam Perth Sydney Port Elizabeth Suez Canal Panama Canal SOUTH AMERICA AFRICA AFRICA ASIA ANTARCTICA AUSTRALIA EUROPE NORTH AMERICA EQUATOR Sri Lanka MID-ATLANTICRIDGEMarianaTrench Strait of Malacca NGM MAPS. SOURCE: “SPATIAL AND TEMPORAL CHANGES IN CUMULATIVE HUMAN IMPACTS ON THE WORLD’S OCEAN,” BEN S. HALPERN AND OTHERS, NATURE COMMUNICATIONS; UNEP-WCMC, WORLD DATABASE ON PROTECTED AREAS (2016) in the effects of harmful land-based ac- tivities, including pollution. In all, the researchers classified more than 40 per- cent of the ocean as “heavily impacted” by human activity. A booming population is chiefly to blame, says biologist Ben Halpern, head of the team that collected the data. Most of the dark areas are in the Northern Hemisphere, where almost 90 percent of humans live. But population alone doesn’t affect marine life. “A lot of the ocean is getting worse, and climate High Low Major shipping port Areas of perennial ice (not included in study) Human influence GEOGRAPHY UNDERWATER Not all parts of the ocean are the same. High ridges and deep trenches affect where human activities are feasible and what areas may be spared. change in particular is driving a lot of those changes,” says Halpern. Still, the story isn’t all bad. Some seas have seen reduced human impact—in parts of the North Atlantic, for example, where there are more fuel-efficient ships and new regulations. In 2016 countries established more than 40 new sites to create more than 1.4 million additional square miles of protected marine areas, shielding much of it from commercial fishing, energy drilling, and other ac- tivities that might otherwise do harm.