"What, this Death Star? It's for climate change."
Deadliestfiction“What, this Death Star? It’s for climate change.”

The United States and 140 other countries have signed or otherwise associated with the Copenhagen Accord, in which it is agreed that the nations of the world should “hold the increase in global temperature below 2°C, and take action to meet this objective consistent with science and on the basis of equity.” For there to be a chance — even just a 50/50 chance — of limiting temperature rise to 2°C, global greenhouse gas emissions must peak by 2020 (earlier for the developed world) and fall by 9 or 10 percent a year every year thereafter.

Nothing like that has ever been done. Not even close. No major energy transition has ever moved that quickly. Carbon emissions have never fallen that fast, not even during the economic collapse brought on by the demise of the USSR. Getting to change of that scale and speed is not a matter of nudging along a natural economic shift, as clean energy cost curves come down and fossil fuels get more expensive. That scale and speed seem to demand something like wartime mobilization.