About Me

My photo
Independent Professional: Experienced educator and management consultant for engineering educational institutions, researcher, trainer, technical consultant on sustainable technologies, related to cement manufacturing and characterisation, using industrial and agricultural wastes in cement and concrete, durability of concrete and fuel cell power.

Tuesday, November 3, 2009

German climate scientist sounds alarm

Hans Joachim Schellnhuber, director of the Potsdam Institute for Climate Impact Research and chair of the German government’s Advisory Council on Global Change says:

“The window of opportunity to avert the most serious impacts of climate change is closing rapidly,”

The climate system has clearly started to drift away from the familiar domain where historic experiences apply. Outside that domain, the risk of highly nonlinear changes in environmental conditions, jeopardizing the livelihoods of billions of people worldwide, is sharply increasing. The Current atmospheric concentration of carbon dioxide of around 387 parts per million (ppm) is already exceeding the ‘safe’ boundary of 350 ppm recently proposed by researchers in the journal Nature. The concentration is much higher than the preindustrial concentration of around 280 ppm and probably higher than ever within the last millions of years.

The global warming of more than two degrees Celsius (3.6 degrees Fahrenheit) above preindustrial levels is regarded as a “dangerous interference” that should be avoided. The temperature increase of more than two degrees Celsius is likely to push components of the Earth’s climate system past critical thresholds, so that these components may “tip” into qualitatively different modes of operation. The climate scientists regard Arctic sea‐ice and the Greenland Ice Sheet as the most sensitive tipping elements, but others, like the Amazon rain forest, monsoon systems and the El NiƱo phenomenon are candidates for surprising society by exhibiting a nearby tipping point.

To limit the risk of disrupting elemental processes in the Earth system and to stop global warming at 2° C, humans could release no more than 750 gigatonnes of carbon dioxide by burning oil, coal, gas and cutting down forests in between 2010 to 2050. Since large amounts of greenhouse gases have already been emitted by industrialized countries, only a small budget of carbon dioxide is left, pointing to the need for large reductions within the near future. The German government’s Advisory Council on Global Change has proposed to move this global budget to the forefront of considerations in creating a new global climate treaty, which is due to be negotiated at COP 15 of the UN Framework Convention on Climate Change (UNFCCC) in Copenhagen in December.