The First Assessment Report of the Intergovernmental Panel on Climate Change1 (IPCC AR1) in 1990 noted that the greatest single impact of climate change might be on human migration. The report estimated that by 2050, 150 million people could be displaced by climate change related phenomenon like desertification, increasing water scarcity, floods and storm etc.
The Stern Review on the Economics of Climate Change in 2006 and a Christian Aid report in 2007 estimated displacement of respectively 200 million and 250 million people by climate change related phenomena.
These are terrifying numbers, especially when you realize that the reports tend to be fairly conservative about the effects of climate change. More recent IPCC reports have actually pulled back the more dramatic predictions about migration even as they intensify warnings about global warming.
A recent study, “Assessing the Impact of Climate Change on Migration and Conflict” by Clionadh Raleigh, Lisa Jordan and Idean Salehyan, surveyed the available literature on disaster migration. They wanted to develop reasonable projections on future migration patterns in response to the direct and indirect changes due to climate change. They concluded that international migration is likely to be quite limited.
This is a result that contradicts what I thought I knew. It may or may not be correct. If it is, climate change could be less disruptive and fewer people will die trying to find new places to live. One key, according to Raleigh, Jordan and Salehyan, is that developed nations have to put in place adaptation and disaster response sytems that help the poorest and most vunerable populations deal with crises. I hope that they are right, and I hope we act on their advice.