A report recently published by leading experts from the US National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine, states in no uncertain terms that abrupt climate changes are not only possible but likely in the future, potentially with large impacts on ecosystems and societies. The committee that prepared the report notes that there is no need to be fatalistic; human and natural systems have survived many abrupt changes in the past, and will continue to do so. Nonetheless, future dislocations can be minimized by taking steps to face the potential for abrupt climate change.

Drawing on the historical record, the scientists note that perturbations of climate in some regions have been spectacularly large: some had temperature increases of up to 16 degrees C and doubling of precipitation within decades, or even single years. There is no reason to believe that abrupt climate changes will not occur again. The Committee recommends additional research to improve the fundamental knowledge base and improve modelling relating to abrupt climate change. In addition, they urge increased efforts to identify “no-regrets” measures to reduce vulnerabilities and increase adaptive capacity at little or no cost. No-regrets measures may include low-cost steps to: slow climate change; improve climate forecasting; slow biodiversity loss; improve water, land, and air quality; and develop institutions that are more robust to major disruptions.

In a section headed Final thoughts, the Committee notes that “the United States and other wealthy nations are likely to cope with the effects of abrupt climate change more easily than poorer countries. This does not mean that developed countries can remain isolated from the rest of the world, however. With growing globalization, adverse impacts—although likely to vary from region to region because exposure and sensitivity will vary—are likely to spill across national boundaries, through human and biotic migration, economic shocks, and political aftershocks. Thus, even though this report focuses primarily on the United States, the issues are global and it will be important to give attention to the issues faced by poorer countries that are likely to be especially vulnerable to the social and economic
impacts of abrupt climate change.”

The 167 extensively referenced report, Abrupt Climate Change: Inevitable Surprises, is available at http://www.nap.edu/catalog.php?record_id=10136