What Targets Should We Adopt? (page 30)

Germany’s Potsdam Institute has found that if we are to keep the rise in temperature below 2C, we can only burn 190 billion tonnes (Gt) of carbon between now and 2050, on top of the 500 billion tonnes we have already burnt. At the current rate of 8.5 Gt a year, we will hit the absolute limit in 22 years. Since we can’t stop suddenly, the world’s nations will need to organize and ration the decline, signing onto a 4-5% annual decrease in their carbon emissions.

The Climate Interactive Scoreboard - an open-source world for climate simulations where you can try out various scenarios. www.climateinteractive.org