Australian Climate Commission on only 16 years left before we exceed the terminal budget (2013): “The budget approach shows that to have a 75% chance of staying within the 2oC limit , we can emit no more than 1,000 billion tonnes of CO2 from 2000 to mid-century. In the first 13 years of this period we have already emitted nearly 400 billion tonnes, about 40% of the total allowable budget (Figure 8). That leaves a budget of just over 500 billion tonnes of CO2 for the next 35-40 years, after which the world economy needs to be completely decarbonised. Worse yet, the rate at which we are spending the budget is still much too high, and is growing. For example, from 2011 to 2012, global CO2 emissions rose by 2.5%. Under a business-as-usual model, with emissions growing at 2.5% per annum, we are on track to have completely used up the allowable global emissions budget within the next 16 years, that is, by 2028.” [1].
[1]. Australian Climate Commission, “The critical decade 2013: a summary of climate change science, risks and responses”, 2013, p7: http://climatecommission.gov.au/wp-content/uploads/The-Critical-Decade-2013-Summary_lowres.pdf .