How climate change may affect farmers and food security in southern Africa depends on a range of crop, climate and economic models, which have been brought together in a new book designed to help policymakers understand and prepare for the coming changes, researchers say.
The book, "Southern African Agriculture and Climate Change", delves into climate challenges facing farmers in Botswana, Lesotho, Malawi, Mozambique, South Africa, Swaziland, Zambia and Zimbabwe.
"Sometimes I think it's helpful for policymakers to see the numbers about the degree to which climate change will impact productivity," said Tim Thomas, a research fellow with the International Food Policy Research Institute, and one of the authors of the book. "It helps them see the mix of population growth, GDP growth and climate change, and how that all melds together."
Three research organizations and scientists from each southern African country worked together to create the book, which they hope is a more useable analysis of available data.
Over the past three years, the researchers looked at crop, climate and economic models to develop a range of different climate change scenarios for each country. They explored how these different scenarios might impact food security, resource management and livelihoods.
TEMPERATURE, RAINFALL CHANGES
Southern Africa is already experiencing rising temperatures, changes in rainfall and more extreme weather events. The region overall is expected to become more food insecure, particularly with a rapidly rising population as well. But the analysis points out important variations between countries.
South Africa, for example, could see higher wheat yields than less temperate parts of the region as temperatures increase; Mozambique could see a rise in maize and sorghum yields, despite declines in much of the region.
Thomas said that more thorough research is needed into how these shifts, both positive and negative, will impact migration between rural areas and cities.
As well, "there are many sensitive environmental areas that might be out of reach now (for agriculture), but with rising temperatures in the future might become very good for crops," Thomas said. "There may be a special need to watch those areas and make sure they stay protected."
As with any analysis of future climate change, there's quite a bit of uncertainty, and many of the crop models and temperature predictions disagree. "That's the thing people don't like, because people like concrete answers," Thomas said.
Policymakers should invest in research that could help develop options for a range of future possibilities, he said. And much more focus should be placed on bringing the fruits of research to farmers, whether that means helping them choose the right seeds or fertiliser, or finding different ways to use crops and conserve water.
"I think in many countries extension services are not reaching a high percentage of farmers," Thomas said. "That really needs to be fortified."
The book is part of a series examining climate change and agriculture in different regions of Africa. A publication focusing on western Africa launched in April and another focusing on eastern Africa will launch in December. The researchers hope their work will fill a gap in climate change analysis, but a main point throughout seems to be that there are few clear answers.
"If you are a policymaker you want to know if it's going to go one way or another, but when you just don't know, then it's a question of what can you do," Thomas said. "Policymakers have to think more in terms of resiliency and flexibility in their policies, rather than solving a specific problem."
Erin Berger is an intern reporting on climate change issues for the Thomson Reuters Foundation.