A widespread farming catastrophe could hit Africa if global temperatures rose by four degrees Celsius or more, according to a study that calls for urgent planning for a much warmer future and investment in technology to avert disaster. In most of southern Africa the growing season could shrink by as much as a fifth, according to scientists at the International Livestock Research Institute (ILRI) in Kenya, who carried out simulation studies based on existing climate change models.
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According to the models, the growing season may increase modestly in eastern Africa. But cropping seasons are likely to decline more quickly everywhere in the region except central Africa. uch of southern Africa's rain-fed agriculture could fail every other season by the 2090s, says the study.
"It is not difficult to envisage a situation where the adaptive capacity and resilience of hundreds of millions of people in Sub-Saharan Africa could simply be overwhelmed by events." Simply making crops more drought-tolerant or flood-resistant is just tinkering about the edges, said Seré. "The changes which will be required in the farming system are quite drastic, pushing farmers beyond the limits of their knowledge and experience. They will be overwhelmed by extreme climate events," he told SciDev.Net.
"We are talking about farmers abandoning cropping and migrating out of those regions. But where are farmers who cannot cope with this level of stress in the system to go? Where is the alternative livelihood for 60 per cent of the continent where farming is still a very key part of coping with food security? You cannot escape the fact that for decades many people are going to be in the rural sector. It is a moral imperative to give those people a livelihood. We need to understand and find much smarter ways to get knowledge out there. Extension services in Africa have largely collapsed in many countries".
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http://www.scidev.net/en/news/four-degree-rise-would-scupper-african-farming-.html