Augustin Lagarde
What’s at stake: France will chair and host the 21st Conference of the Parties to the United Nations Framework Convention on Climate Change (COP21) at the end of the year. While the scientific community has reached a consensus that climate-warming trends are very likely due to human activities, the discussion about how to address is mired in huge political disagreements.
John Cook et al. examined 11 944 abstracts of peer-reviewed scientific literature published between 1991–2011 on the topics ‘global climate change’ or ‘global warming’. Among abstracts expressing a position on anthropogenic global warming, 97.1% endorsed the consensus position that humans are causing global warming – a rare level of agreement in the world of science!However, there is controversy about the validity of this result. Richard Tol pointed out that the paper did not meet basic academic standards, although the authors answered this criticism. The debate, more about academic rigor than about the fact that there is a consensus, is still ongoing (see here, here and Figure 1). In fact, Tol wrote:“There is no doubt in my mind that the literature on climate change overwhelmingly supports the hypothesis that climate change is caused by humans. I have very little reason to doubt that the consensus is indeed correct.”
Let us return to the political discussion. In 2009 the COP15 in Copenhagen did not result in a consensus. Parties did not adopt a successor of the Kyoto Protocol. Instead the Doha Conference (Qatar) in 2012 established a second commitment period of the Kyoto Protocol (2013-2020), which concerned only a number of industrialised countries. In December in Paris, the expected outcome is a new international agreement on climate change, applicable to all, to keep global warming below 2°C.
