Map of World's Oceans -The Human Impact

Only about 4% of the world's oceans remain undamaged by human activity, according to the first detailed global map of human impacts on the seas created by an international team of 20 scientists in the US, Canada and UK who built a complex model to handle large amounts of information on 17 different human threats.

A study in Science journal says climate change, fishing, pollution and other human factors have exacted a heavy toll on almost half of the marine waters.The only relatively pristine areas are remote ice-bound regions near the poles, which face threats as ice sheets melt.

"I think the big surprise from all of this was seeing what the complete coverage of human impacts was," said Dr Mark Spalding, The Nature Conservancy lead scientist, Dr Benjamin Halpern, of the National Center for Ecological Analysis and Synthesis in Santa Barbara.

"In the past, many studies have shown the impact of individual activities," he said. "But here for the first time we have produced a global map of all of these different activities layered on top of each other so that we can get this big picture of the overall impact that humans are having rather than just single impacts."

Co-author Dr Mark Spalding told BBC News that the map was the first attempt to describe and quantify the combined threats facing the world's oceans from human factors, ranging from commercial shipping to over-fishing.

"There's an element of wake-up call when you get maps like this," he said. "Human threats are all pervasive across the world's oceans.

"The map is an impetus for action." He said the two biggest drivers in destroying marine habitats were climate change and over-fishing.

"Out on the high seas, climate change and fishing were far and away the strongest influences," he explained. "The least impacted areas are the polar regions but they are not untouched."

The findings of the study were presented at the annual meeting of the American Association for Advancement of Science (AAAS) in Boston, US.

Posted by Casey Kazan.

Source:

http://news.bbc.co.uk/2/hi/science/nature/7241428.stm

Comments

[martin weiss]

This map lacks evidence of the hundreds of thousands of tons of radioactive waste dumped in the oceans by the US, Britain, France and the Soviet Union.