The draft 2013 Fifth Assessment report of the Intergovernmental Panel on Climate Change makes clear inaction on climate change would be devastating to modern civilization. The report finds that the human fingerprint on climate has grown more obvious, concluding “it is virtually certain” the energy imbalance that causes global warming “is caused by human activities, primarily by the increase in CO2 concentrations. There is very high confidence that natural forcing contributes only a small fraction to this imbalance.”