Originally posted at Skeptical Science
From 1989 to 2002, several large US companies, including the oil companies Exxon and the US subsidiaries of Shell and BP, sponsored a lobbying organisation called the Global ClimateCoalition (GCC), to counter the strengthening consensus that human carbon dioxide emissions posed a serious threat to the Earth’s climate. As has been documented by Hoggan and Littlemore and Oreskes and Conway, the GCC and its fellow travellers took a leaf out of the tobacco industry’s playbook and attempted to counter the message of peer-reviewed science by deliberately sowing doubt through emphasizing uncertainties and unknowns. The climatescientist Benjamin Santer accused the GCC of deliberately suppressing scientific information that supported the IPCC consensus.
Originally posted at Skeptical Science and reposted at Climate Progress.
A recent modelling experiment shows that climate change feedbacks from thawing permafrost are likely to increase global temperatures by one-quarter to a full degree Celsius by the end of this century. This extra warming will be in addition to the increase in temperature caused directly by emissions from fossil fuels. Even in the unlikely event that we were to stop all emissions in the near future, this permafrost climate feedback would likely continue as a self-sustaining process, cancelling out any future natural draw-down in atmospheric carbon dioxide levels by the oceans or vegetation. Avoiding dangerous climate change by reducing fossil-fuel emissions becomes more difficult once permafrost emissions are properly considered.