Editorial on Tipping Elements online-hit of PNAS
PNAS Cover image. Images: glacier courtesy of Ulrich Heim (Luebeck, Germany), methane bubbles courtesy of Alfred Wegener Institute, dust cloud courtesy of NASA, and Amazon rainforest courtesy of Greenpeace
In the paper, which introduces the journal’s Special Feature, Schellnhuber examines elements of the Earth system whose state could be altered by anthropogenic forces. Further, he outlines nine studies published by international experts concerned with the stability of tipping elements, such as the Indian monsoon, the Amazon rainforest and continental ice sheets. On account of persistent scientific uncertainties and the risks associated with tipping processes, Schellnhuber concludes that tipping elements pose one of the toughest challenges for contemporary science.
