Weather: Predictions of doom and disaster

A new report paints a grim picture of the potential consequences of global warming. Islands will be submerged, Europe could suffer water shortages, urban air quality could deteriorate in North America, Africa could starve ... if current computer models are correct.

The Regional Impacts of Climate Change has just been published by Cambridge University Press (pounds 24.95 paperback, pounds 70 hardback) to coincide with the end of the Kyoto conference on global warming. In more than 500 pages of tables and analysis, this report by the Intergovernmental Panel on Climate Change takes us on a tour of the world, continent by continent, examining the present interaction between climate and natural resources, and how things could change if the earth continues to get warmer. And it paints a dismal scenario.

"Based on the range of sensitivities of climate to changes in the atmospheric concentration of greenhouse gases and plausible changes in emissions of greenhouse gases and aerosols," it says, "climate models project that the mean annual global surface temperature will increase by 1-3.5C by 2100, that global mean sea level will rise by 15-95cm, and that changes in the spatial and temporal patterns of precipitation would occur. The average rate of warming probably would be greater than any seen in the past 10,000 years."

Having set the scene for climactic climatic change, the report moves on to discuss the impact on ecosystems, water availability, food production and human health in various areas of the world. In Africa, some models predict less rain and a drop in water level in dams and rivers which "could adversely affect the quality of water by increasing the concentrations of sewage waste and industrial effluents, thereby increasing the potential for the outbreak of diseases".

In Latin America, climate change could lead to a reduction in fish quality and stocks, increasing storms and the inundation of coastal zones and small islands. In Central America, it's floods they have to worry about. In the Middle East, water shortages are expected to be exacerbated, which will lead to increased problems with food production.

In North America: "in some cases, changes in climate will provide adaptive opportunities or could alleviate the pressure of multiple stresses; in other cases climate change could hasten or broaden negative impacts, leading to reduced function or elimination of ecosystems." Europe also has good and bad news: more heat-related deaths in the summer; fewer cold-related deaths in the winter. But summer air pollution will get worse, and "some vector-borne infectious diseases will have the potential to extend their range."

The ambition of the book is "to become the primary source of information on regional aspects of climate change for policymakers, the scientific community, and students", and it certainly contains all the information needed for anyone attempting a serious study of the affect of climate on the environment. There are tables of water resources, energy use, economic conditions, population density, arable land, agricultural land and even the stocks of cattle, sheep, pigs, and everything to camels and goats in every country on earth. (Oddly enough, nobody seems to have counted the number of goats in the UK.)

But are the models to be trusted? Global warming sceptics will find plenty of ammunition in sentences such as this: "Possible local climate effects which are due to unexpected events like a climate-change induced change of flow pattern of marine water streams like the Gulf Stream have not been considered, because such changes cannot be predicted with confidence at present."

If we can't even confidently predict whether the Gulf Stream - which has such a major effect on our climate - is going to change direction, can we really trust the other conclusions?