Poor countries will suffer massive losses of food production and agricultural land as global warming takes hold but North America will benefit, a United Nations report released at the summit said.
The conclusions – which add a new dimension to the Bush administration's rejection of the Kyoto Protocol to combat climate change – show food production declining sharply in up to 73 countries during the next eight years, even as their population grows.
It says growing wheat will "virtually disappear from Africa", and decline by up to 95 per cent in South-east Asia and up to 75 per cent in the Indian sub-continent. Other crops such as sugar and roots and tubers crops will also decline, though not by so much.
The report – prepared by the International Institute for Systems Analysis in Austria for the United Nations – is based on a series of sophisticated computer models of climate and food production from some of the world's leading institutes in the field.
It says that arid areas will get larger in developing countries worldwide. Growing crops will become much harder in Southern Africa, where another 11 per cent of its total land area "may suffer from severe constraints" on agriculture by the year 2080. Central America and the Caribbean, Australia, Northern Africa, and the Middle East will also lose available land.
Parts of Europe – and particularly Britain, Ireland and Spain – will lose good land because rainfall patterns will change, bringing drier summers. But other parts, such as Scandinavia, will gain when cold northern areas warm up.
Northern America and Russia will also gain land in that way and are expected to be able "substantially" to increase production. By contrast, up to 40 developing countries – which are expected to be home to up to three billion people in 2080 – may lose up to a fifth of their harvests and another 33 would could lose about 5 per cent of it. Among the most seriously affected countries are Sudan, Nigeria, Senegal, Mali, Burkina Faso, Ethiopia, Zimbabwe, Somalia, and Mozambique.
The number of hungry people will increase, says the report, and the world will become even more dependent on the United States for food. At present, US farmers help to feed more than 100 countries who import its grain and the report predicts developing country imports will increase by 25 per cent in the next 80 years.
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