LONDON: Climate change will raise average crop productivity until 2020, after which it will decline by 5-10% by 2050, North African agriculture will be the worst affected, according to Colombian research.
The researchers looked into how 50 key crops will perform around the world under increasing temperatures over the next 40 years in a study carried out by the International Centre for Tropical Agriculture (CIAT) in Colombia.
The results come ahead of a formal announcement in early December of the launch of The Climate Change, Agriculture and Food Security program, a 10-year research initiative by Consultative Group on International Agricultural Research (CGIAR) to address the effects of climate change on food security.
Northern Hemisphere: gains until 2020
CIAT researchers calculated the 'climatic potential to produce food' for 50 of the world's most important crops. This is the hypothetical best-case scenario in which crops can be shifted to more suitable zones to avoid the worst, or exploit the best, climate impacts.
They concluded that most of the short-term gains until 2020 will be seen in the Northern Hemisphere. Andy Jarvis, a research fellow at CIAT, said that rice yields on the Indo-Gangetic plains will increase by around 2%, even up to 2050. But wheat will experience productivity losses of up to 10%.
In West Africa, important crops such as wheat, potato, sorghum and soya will lose out, while more robust crops such as white yam, sugar cane and plantain will benefit from the higher temperatures.
North Africa: 80% crops losing productivity
In East Africa, similar patterns will be seen, with beans — known as the protein of the poor — predicted to experience yield losses of 3-5%. North Africa will experience the worst effects, with 80% of its crops losing productivity to 2050 and beyond.
"There is no single region where all crops are losing productivity," said Jarvis, "but people are depending on very specific crops for their food security, and in many cases the crop they're growing today is going to lose out in the future.
"Local cultures may need to change their practices by growing different crops from what they grow today. That is obviously quite an upheaval for those communities, and it's something that we need to work towards and try to avoid if possible," he said.
Changing planting times cause havoc
Even in areas where significant increases in crop yields are seen, there will be other knock-on effects, he added.
For example, farmers on the Indo-Gangetic plain are already experiencing lower wheat yields because of increased temperatures. Changing wheat planting times means changing rice planting times — as the two are grown in cycles — which causes problems with irrigation.
The new program aims to reduce poverty in targeted regions by 10%, and reduce the number of rural malnourished poor by a quarter, by 2020. It also hopes to put agriculture on the post-2012 international climate-change agenda.
This news story was originally published on SciDev.net
