Worst Case Carbon Dioxide Emissions Increases Continue — Hitting 40 Billion Tons Per Year in 2013 | (Global carbon emissions continued along a worst-case track during 2013. Note that estimated temperature increases are for this century only. For context, it took 12,000 years for the world to warm 5 degrees Celsius at the end of the last ice age. Image source: Global Carbon Project.)
On the current track, global CO2 emissions will double in about 30 years. This pace of emissions increase is along the worst-case path projected by the UN’s IPCC. One that will hit 8.5 watts per meter squared of additional warming at the top of the Earth’s atmosphere and greater than 1,000 ppm CO2 equivalent greenhouse gas heat forcing by the end of this century.
Such a massive increase from human sources does not include amplifying feedback emissions from global methane or CO2 stores such as those now apparently destabilizing in the Arctic. Such emissions could add an additional 20 to 30 percent or greater heat forcing on top of the human forcing, according to scientific estimates, by the end of this century.
The massive blow would be more than enough to trigger a hothouse extinction event — one that could well rival or exceed the Permian (also known as ‘the great dying’) in its ferocity due to the very rapid pace of the human heat accumulation. |