Time short to protect Africa's food supply from climate change: study

By Megan Rowling

BARCELONA, March 7 (Thomson Reuters Foundation) - Without action to help farmers adjust to changing climate conditions, it will become impossible to grow some staple food crops in parts of sub-Saharan Africa, with maize, beans and bananas most at risk, researchers said on Monday.

In a study of how global warming will affect nine crops that make up half the region's food production, scientists found that up to 30 percent of areas growing maize and bananas, and up to 60 percent of those producing beans could become unviable by the end of the century.

Women sort beans as they prepare a meal at Kasese District Uganda.REUTERS/James Akena

Six of the nine crops - cassava, groundnut, pearl millet, finger millet, sorghum and yam - are projected to remain stable under moderate and extreme climate change scenarios.

"This study tells where, and crucially when, interventions need to be made to stop climate change destroying vital food supplies in Africa," said Julian Ramirez-Villegas, the study's lead author who works with the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS).

"We know what needs to be done, and for the first time, we now have deadlines for taking action," he added in a statement.

For example, the study warns that around 40 percent of maize-growing areas will require "transformation", which could mean changing the type of crop grown, or in extreme cases even abandoning crop farming.

Sorghum and millet, which have higher tolerance to drought and heat, could replace maize in most places under threat.

But for 0.5 percent of maize-growing areas - equal to 0.8 million hectares in South Africa that now produce 2.7 million tonnes - there is no viable crop substitution, the study said.

In a few places, the need to adapt to climate change is already urgent, the researchers said. Those include pockets in highly climate-exposed areas of the Sahel in Guinea, Gambia, Senegal, Burkina Faso and Niger.

Banana-growing regions of West Africa, including areas in Ghana and Benin, will need to act within the next decade, as the land is expected to become unsuitable for bananas by 2025.

And maize-growing areas of Namibia, Botswana, Zimbabwe and Tanzania also have less than 10 years left to change tack under the most extreme climate change scenarios, the study added.

"If we don't do anything now, farmers are no longer going to be able to grow certain crops in certain sites," Ramirez-Villegas told the Thomson Reuters Foundation from Colombia.

"But we know there are several adaptation options ... with which farmers should be able to carry on growing these crops for a longer period of time than we project."

Read the full story at Building Resilience and Adaptation to Climate Extremes and Disasters (BRACED).