Seasonally adjusted
Oct 1st 2009
From The Economist print edition
Global warming will make it harder to feed the world in 2050
SINCE time immemorial, farmers have planted their crops according to the seasons. “That is what my forefathers have been doing,” says Mohammad Ilisasuddin in Shibganj, in northern Bangladesh, but now “the weather does not seem right for what we have done traditionally.” Seasonal planting is “useless”, agrees Florence Madamu, a smallholder in Bulirehe, in western Uganda. “The sun is prolonged until the end of September and whenever it rains, it rains so heavily it destroys all our crops.” Oxfam, a British charity, has compiled a litany of laments by poor farmers. John Magrath, a researcher, says they all say similar things: “moderate, temperate seasons are shrinking…rainy seasons are shorter and more violent…making it more difficult to grow crops [and] difficult for them to know when best to plant.”
As the earth warms up, many have feared that farmers will pay a high price. But working out who will pay, how, and where is tricky. Higher temperatures might turn arid shrub lands into deserts while improving the growing season in colder steppes. Global warming could produce more evaporation from plants, and more rain, which would benefit some places, while hurting others. In theory extra carbon dioxide in the atmosphere should help plants grow faster, though whether this actually happens may also depend on the amount of nitrogen in the soil.
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