James Hansen, head of the Nasa Goddard Institute for Space Studies in New York, calls for a sharp reduction in C02 limits warning the EU and its international partners that they must urgently rethink targets for cutting carbon dioxide in the atmosphere because of fears they have grossly underestimated the scale of the problem.

Hansen says the EU target of 550 parts per million of C02 – the most stringent in the world – should be slashed to 350ppm. He argues the cut is needed if “humanity wishes to preserve a planet similar to that on which civilisation developed” and that even 450 ppm will translate to a sea rise of 75 metres and at 550ppm, the world would warm by 6C not the 3C as previously estimated. The paper co-authored with eight other climate scientists, is here. The team studied core samples taken from the bottom of the ocean, which allow C02 levels to be tracked millions of years ago and are more accurate that theoretical modeling. They show that when the world began to glaciate at the start of the Ice age about 35 million years ago, the concentration of CO2 in the atmosphere stood at about 450ppm.

Hansen said his findings were not a recipe for despair. The good news, he said, is that reserves of fossil fuels have been exaggerated, so an alternative source of energy will have to be rapidly put in place in any case. Other measure could include a moratorium on coal power stations which would bring the C02 levels to below 400ppm.

via: The Guardian