By 2020, the report warns, up to 250 million Africans may be left short of water, ...

Grim outlook for poor countries in climate report | David Adam, Peter Walker and Alison Benjamin | Guardian Unlimited | Tuesday September 18 2007
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Professor Martin Parry, a climate scientist with the Met Office, said destructive changes in temperature, rainfall and agriculture were now forecast to occur several decades earlier than thought.
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The report – which had its executive summary released earlier this year – says hundreds of millions of people in developing nations will face natural disasters, water shortages and hunger due to the effects of climate change.
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Today's report concludes that while the impact of a warmer globe will have mixed effects – for example, it notes that crop yields could increase in northern Europe – the overall impact will be deeply negative, particularly in Africa, in the so-called "mega-deltas" of south and east Asia, and on small islands and in polar regions.

By 2020, the report warns, up to 250 million Africans may be left short of water, while access to sufficient food is "projected to be severely compromised by climate variability and change". ...