New modeling released by the United Nations today paints a very disturbing picture – the emission cuts pledges made by the 60 countries who signed the Copenhagen Accord will not be enough to keep the average global temperature rise low enough to avoid devastating climate change. The simple explanation is in order to stay in the safe zone, scientists say temperatures need to be limited to a rise of no more than 2 degrees Celsius (3.6 F) above pre-industrial times. Unfortunately, the new study shows that even if every country that promised to cut their greenhouse emissions does so at the levels agreed to (and who knows if that will even happen?), the total amount of emissions produced would still be gigatonnes over what scientists view as tolerable.
To break it down even further, the United Nations Environment Programme (UNEP) says that annual greenhouse gas emissions should not be more than between 40 and 48.3 gigatonnes of CO2-equivalent in 2020 and should peak between 2015 and 2021. The report, which was based on modeling by nine research centres, also said that if we stay inside that range and slash global emissions by between 48 and 72 percent between 2020 and 2050, Earth will have a or 50-50 chance of staying within the 2 degree limit.
However, the report went on to say that based on the vows made in the Copenhagen Accord, “the expected emissions for 2020 range between 48.8 to 51.2 gigatonnes of CO2-equivalent, based on whether high or low pledges will be fulfilled.” If you compare the numbers, it’s easy to see that the promised cuts will still result in emissions that are 0.5 and 8.8 gigatonnes over what scientists see as the cap.