HALF A DEGREE TO GLOBAL CATASTROPHE

'Confronting Climate-Change: Avoiding the Unmanageable, Managing the Unavoidable', written by an expert panel (SEG) organised by Sigma Xi, the scientific honour society, and sponsored by the United Nations Foundation, is outlined in the May/June issue of Update, the magazine of the New York Academy of Sciences. The report says accumulating evidence suggests that climate-change may not be gradual. Several major tipping-points, such as the collapse West Antarctic ice-shelf, major melting of the Greenland ice-cap, desertification of the Amazon rain-forest, and changes in the frequency of strong El Nino oscillations could cause sudden and catastrophic changes over a few years rather than a few centuries. The authors conclude that allowing the global surface temperature to rise more than 2 to 2.5 degrees Celsius over the next hundred years would sharply increase the risk those catastrophic impacts. Greenhouse gases now in the atmosphere have already committed the planet to a rise of about 1.5 degrees.

We are therefore only 0.5-1.0 degrees away from the risk of swift catastrophe.

To stay within the recommended range, the researchers say greenhouse-gas emissions must stablise at not much more than present levels by 2015 at the latest, then fall to no more than a third of present levels by 2100.

Fat chance!

The sea is rising at about 3mm a year and Antarctic glaciers are surging along, which the IPCC report did not factor in.

For the full Sigma Xi SEG report, click here.