On this issue, Hans Joachim Schellnhuber, director of the Potsdam Institute for Climate Impact Research:
"If China would indeed set an absolute national cap on greenhouse gas emissions, this would mean a boost for finding global solutions to tackle the climate challenge. It is most remarkable that now both China and the US seem to be ready to show renewed leadership. Science keeps on demonstrating that the world is about to reach more and more tipping points in the climate system, such as the recently detected and probably irreversible ice-melt in the western Antarctic, eventually causing substantial sea level rise. So the big question is how stringent China's cap of emissions will be.
For Europe, host of the 2015 climate summit, it might be about time to wake up from its recent climate fatigue. The example it set with its cap-and-trade system (ETS) finally finds followers, so the EU could pioneer further by setting more ambitious climate targets and by immediately reforming the ETS. Research shows that it would make sense to include the transport and heat sectors into the cap-and-trade system. The science is clear that the later we act, the more costly it gets in the economic system, and the more risky in the climate system."
