The United Nations Intergovernmental Panel on Climate Change (IPCC) has given its starkest warning of the likely impact of climate change. The IPCC’sMarch 31 report, the most comprehensive yet, states that the evidence of global warming is now overwhelming, and warns that all countries and all social classes of people will be affected by changes which are likely to be “severe, pervasive and irreversible.” All animal species face an increased risk of extinction, and vegetation patterns are likely to change substantially, with low-latitude species appearing in higher latitudes and lower latitudes becoming more arid, even if rainfall patterns there are becoming less predictable. If temperatures rise to 2 ˚ C or more above 20th century levels, yields of major food crops will probably fall; the likely yield increase in colder climates as those grow warmer may not offset declining yields elsewhere. Water resources, already under stress in Asia, are likely to come under even greater stress, and ocean acidification — caused by the absorption of rising levels of atmospheric carbon dioxide — is likely to compound the problems. The poor in all countries are likely to suffer more than the rich, but all humanity may well be unable to adapt to temperature rises of above 2 degrees.
While the report is not apocalyptic in tone, and specifies the level of confidence with which it states its main findings, one major question arising thence is whether we can adapt to survive, or whether far more drastic measures are required. This is especially important in South Asia, where almost one and a half billion people live. Spreading aridity, or increasingly severe individual events like storms or droughts, not to mention the disappearance of land as sea levels rise, could well lead to large-scale migration, which in turn could cause resource-driven conflict not between countries but between rural and urban populations or between crop farmers and animal farmers. Existing inequalities are likely to worsen, which will make it harder for people to climb out of poverty. Yet, on the evidence the report has received only the briefest of responses, for example from United States Secretary of State John Kerry, and from the environment ministers of various European Union countries; moreover, the very possibility that gradual adaptation may not avert climate catastrophe appears not to figure, particularly in regions which would be the worst affected, such as South Asia. That countries — states — are the only bodies even remotely capable of action on the scale required hardly needs saying, but the regions at greatest risk have some of the world’s most dysfunctional states. We cannot say we have not been warned.