Climate Near Tipping Point: Immediate Action Needed

June 1, 2007 – Vol.12 No.10

CLIMATE NEAR TIPPING POINT: IMMEDIATE ACTION NEEDED.

In the lead up to this year’s G8 summit, the Bush Administration has laid out new plans for tackling global warming: Have a meeting of the 10 - 15 largest greenhouse gas emitters (including China and India and the US of course); ask them to draw up plans over the following 18 months on how best each nation can cut its own emissions; share greenhouse gas cutting technologies among nations and industry (and ask other nations to do the same); and create a transparent system to measure the efforts to cut emissions.

But, no timetables, no specific caps on emissions.

German Chancellor Angela Merkel, leader of G8 host nation, has called for a cut in global emissions of 50 percent below 1990 levels by 2050 to slow the average rise in temperature to 3.6 F (2 C) for this century.

US House Speaker Nancy Pelosi, fresh back from a climate change fact-finding trip to Greenland, Germany, England, and Belgium said regarding the Presidents plan’s. ”Technology transfers and voluntary emissions targets are not enough to reverse global warming.”

Environmental advocacy group Environmental Defense wants the US Congress to pass, and the President sign, a cap and trade bill.

And respected global business and industry watcher The Economist says in a new special report on climate change, that industry is ready to take on the challenge of global warming and the technology to cut greenhouse gas emissions is already there to do so. Report author Emma Duncan says that business caused the problem of climate change, and business can solve it, but concludes that industry and consumers can’t bear the brunt of the costs. Government has to step in with incentives.

All this sounds like more time squandered in talking and debate.

A new report from NASA Goddard Institute for Space Studies and the Columbia University Earth Institute says that only moderate additional warming of the planet, an additional 1C degree (1.8 F) (half of what Merkel is asking for) is likely to be dangerous. Only moderate additional climate forcing is likely to set in motion disintegration of the West Antarctic ice sheet and Arctic sea ice. Antarctica has already lost more ice to the sea than it has gained back in snowfall.

A tipping point - the moderate increase in average global temperatures - would result in a feedback loop where dark areas, such as the surface of the oceans surrounding the ice caps, absorb additional sunlight due to increase in area due to already ongoing ice melt. The sunlight-warmed waters would accelerate the melting of adjacent ice.

The feedback loop would amplify and continue as more and more previously ice covered ocean absorbed more sunlight instead of reflecting it back into space.

Of particular concern would be a melting of the West Antarctic ice sheet that is now held back from flowing into the ocean by ice shelves. If the shelves go the ice sheets move more rapidly to the ocean, melt, and global sea level rises - noticeably.

Authors of the report think that CO2 levels of 450 parts per million is dangerous, perhaps too high. We’re now at 382 parts per million and rising at about 2 ppm per year.

(Another recent report says that carbon emissions are accelerating, which makes sense because of the economic growth of India and China.)

Even if measures to cut greenhouse gas emissions were decided on today, they’d take years to implement and see results; thus the need for immediate action. The sooner we get started the safer we’ll be.

The research appears in the current issue of Atmospheric Chemistry and Physics.

Visit the NASA Goddard Institute for Space Studies http://www.giss.nasa.gov/ Columbia University Earth Institute http://www.earthinstitute.columbia.edu/ Environmental Defense at http://www.environmentaldefense.org/