Green gas effect

Map of man’s influence on the Ocean

By admin ⋅ February 16, 2008 ⋅  Email This Post ⋅  Print This Post ⋅ Post a comment ⋅ 176 views

This comprehesive map is shows the tremendous impact man had on the marine environment, affecting 41% of the world’s ocean, no area remaining completely untouched. Presented Thursday at the annual meeting of the American Association for the Advancement of Science, the map takes into account the impact 17 different activities have on the marine life, ranging from fishing and commercial shipping to pollution and climate change.

Photo credit: Ben Halpern / NCEAS

This global map shows cumulative human impact across 20 ocean ecosystem types. The map is color-coded to show very high impact (red), high impact (dark orange), medium high impact (light orange), medium impact (yellow), low impact (green) and very low impact (blue). 41% of the area has experienced medium high to very high impact, scientists say.

Among the highly impacted pieces of that delicate ecosystem are the coral reefs, continental shelves and the deep ocean. The biggest human impact was seen in the North Sea, the South and East China Seas, the Caribbean and North America’s East Coast. The areas that suffer the least, according to the map were largely near the poles.

“For the first time, we have produced a global map of all of these different activities, laid on top of each other, so that we can get the big picture of all the impacts humans are having,” Ben Halpern, the study’s lead author, told journalists Thursday. According to the team, oxygen levels had fallen to virtually nil, and they reported the “complete absence” of fish from rocky reefs. They said the zone’s degradation seemed to be accelerating.

Here is a more detailed look at four areas on the global map. They show, from left, the Eastern Caribbean; the North Sea; the waters around Japan; and one of the world’s least-affected ocean regions, around northern Australia and the Torres Strait.

The group of scientists mentioned their assessment depended on “expert judgment,” and that the method resulted in “a different picture of ocean condition compared with simply mapping the footprints of human activities or drivers.”

“Unfortunately, as polar ice sheets disappear with warming global climate and human activities spread into these areas, there is a great risk of rapid degradation of these relatively pristine ecosystems,” Carrie Kappel, a scientist at NCEAS, said in a news release.

NCEAS’ Halpern said the news wasn’t all bad.

“Small patches of these low-impact areas exist around the planet,” he said. “Almost every country has some of these in their backyard, providing real opportunities for effective management and conservation in these areas.”
source: MSNBC

Tags: activism, destruction, environment, impact, oceans, planet, save