Global warming and food -- or the lack thereof

The Globe and Mail's Martin Mittlestaedt on why some experts think food supply might be among the first major casualties of global warming.

An excerpt:

That's the view of a small but influential group of agricultural experts who are increasingly worried that global warming will trigger food shortages long before it causes better known but more distant threats, such as rising sea levels that flood coastal cities.

The scale of agriculture's vulnerability to global warming was highlighted late last year when the Consultative Group on International Agricultural Research (CGIAR), an umbrella organization representing 15 of the world's top crop research centres, issued an astounding estimate of the impact of climate change on a single crop, wheat, in one of the world's major breadbaskets.

Researchers using computer models to simulate the weather patterns likely to exist around 2050 found that the best wheat-growing land in the wide arc of fertile farmland stretching from Pakistan through Northern India and Nepal to Bangladesh would be decimated. Much of the area would become too hot and dry for the crop, placing the food supply of 200 million people at risk.

"The impacts on agriculture in developing countries, and particularly on countries that depend on rain-fed agriculture, are likely to be devastating," says Dr. Louis Verchot, principal ecologist at the World Agroforestry Centre in Nairobi, Kenya.

Wheat, the source of one-fifth of the world's food, isn't the only crop that could be clobbered by climate change. Cereals and corn production in Africa are at risk, as is the rice crop in much of India and Southeast Asia, according to Dr. Verchot.

In a cruel twist of fate, most of the hunger resulting from global warming is likely to be felt by those who haven't caused the problem: the people in developing countries. At the same time, it may be a boon to agriculture in richer northern countries more responsible for the greenhouse gas emissions driving climate instability.

"With climate change, the agricultural areas in Canada, Russia and Europe will expand, while the areas suited for agriculture in the tropics will decline," Dr. Verchot says. "Basically, the situation is that those who are well off now will be better off in the future, and those who are in problems will have greater problems."