Climate change caused dramatic changes in Antarctica 14 million years ago
mongabay.com
August 25, 2006


Climate change 14 million years ago produced catastrophic drainage of subglacial lakes in Antarctica causing dramatic changes in the continent's landscape according to new research.



In the July issue of the journal Geology, Scientists from Syracuse University and Boston University report that the rapid draining of subglacial lakes caused flooding that formed a 50-kilometer maze of canyons in Antarctica's southern Victoria Land. The research is significant because it suggests what the future could hold should global temperatures continue to climb.

Six hundred meters wide and 250 deep, the Labyrinth is a maze of canyons in Antarctica's southern Victoria Land. Its origin has remained a mystery for years. Photo by David R. Marchant.



The researchers say that the release of an "enormous, forceful volume" of freshwater, like that which occurred millions of years ago, could impact the stability of the East Antarctic ice sheet and disrupt the Southern Ocean circulation, contributing to regional and global climatic changes. The effects could "alter the delicate balance of the Earth's ecosystems" they warn.

"There is no doubt that global climate change has occurred throughout Earth's history," said Suzanne Baldwin, Syracuse University earth sciences professor and director of the Syracuse University Noble Gas Isotope Research Laboratory. "But the current warming trend that we are experiencing is human-induced. We need to act now to reduce greenhouse gas emissions. Global leadership is desperately needed to attack the problem of global warming."

"There are plenty of steps we can take to reduce greenhouse gas emissions," Baldwin added. "The public needs to take the opportunity to educate itself concerning what can be done to reduce them. Seeing the movie ‘An Inconvenient Truth' will give people a better appreciation of the potential problems we will face if we simply decide to do nothing and if the current attitude of ‘business as usual' prevails."

Other scientists have warned that global warming could cause glacial meltwater to raise global sea levels by more than 20 feet by the end of the century, inundating island nation and flooding the world's densely populated coastal areas.

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This article is based on a news release from Syracuse University.






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mongabay.com (August 25, 2006).

Climate change caused dramatic changes in Antarctica 14 million years ago.

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