Climate change is without question the single most important issue the world faces over the next hundred years. The most recent scientific data have led to the conclusion that the globally averaged net effect of human activities since 1750 has been one of warming and that continued greenhouse gas emissions at or above current rates would cause this process to continue to the severe detriment of our environment. This unequivocal link between climate change and human activity requires an urgent, world-wide shift towards a low carbon economy and coordinated policies and measures to manage this...