Thomas Bernauer from the Institute for Environmental Decisions in Zurich. "Our review of existing research demonstrates, however, that there is no consensus in the scientific literature on what the answers to these questions should be."...
"We did find evidence that there is an increased risk of climate change leading to conflict in the poorer, politically unstable countries," said Bernauer. "But even in these cases, there are a lot of factors that lead to conflict and it is difficult to isolate climate change from all the other factors."The conclusions "no consensus on whether X causes Y" or "sometimes X causes Y" are completely different from the conclusion "X does not cause Y." Disappointed by the sloppy logic of the press release, I read the actual article and was further disappointed. The authors are liberal in their sequencing of scientific results when they begin a paragraph by mentioning our 2011 paper, then link it to Marshall's 2009, which they suggest was debunked by Halvard Buhaug's 2010 paper:
Hsiang et al (2011) study the impact of planetary-scale climatic changes on civil conflict and show that the 'probability of new civil conflicts arising throughout the tropics doubles during El Niño years relative to La Niña years.' Similarly, Burke et al (2009) find that temperature increases in Africa between 1981 and 2002 have a significantly positive effect on civil war onset. They report that a 1 °C temperature increase boosts the risk of civil war by 4.5% points during the same year. Buhaug (2010), on the other hand, shows that this result is not robust to alternative model specifications. He also finds that climate variability, measured as inter-annual growth and deviation from annual mean precipitation and temperature, does not predict civil conflict.Now, there are actual issues and debates in the literature that Buhaug, Burke et al., my coauthors and I have discussed and are trying to understand. But this is a very misleading representation of how the various findings fit together. Buhaug's 2010 criticism of Burke et al.'s 2009 paper is a real issue, but it doesn't apply to our 2011 paper. We directly address all of the issues the Buhaug raised, since we were able read them (in 2010) and think about them carefully before we published our paper (in 2011). By structuring the review in this out-of-sequence order, the authors imply that our 2011 results are weakened by 2010 findings that we directly addressed.
The authors are careful not to explicitly state that Buhaug (2010) applies to our 2011 paper, but the misleading implicit suggestion that this is the case is neither logical nor helpful for advancing our scientific understanding.