David Lobell of the Stanford University's Programme on Food Security and the Environment says the world community should focus its efforts where climate threats are likely to make the greatest impacts.
Investments aimed at improving agricultural adaptation to climate change inevitably favor some crops and regions over others. An analysis of climate risks for crops in 12 food-insecure regions was conducted to identify adaptation priorities, based on statistical crop models and climate projections for 2030 from 20 general circulation models. Results indicate South Asia and Southern Africa as two regions that, without sufficient adaptation measures, will likely suffer negative impacts on several crops that are important to large food-insecure human populations. We also find that uncertainties vary widely by crop, and therefore priorities will depend on the risk attitudes of investment institutions.
A man holds a cob of maize as fields and crops were flooded after the Volta Blanc river overflowed due to heavy rain in 2007 in northern Ghana. Climate change will cause severe crop losses in Africa and Asia within the next 20 years unless farming practices are changed, a study released Thursday has found.
An already hungry Southern Africa could face a 30-percent decline in maize production in the next two decades. Production of other staples like millet and rice are projected to fall by at least 10 percent, the analysis found. "Rainfall and temperatures in the region are changing quite fast," Lobell said. Maize requires a great deal of water and rich soils -- or lots of fertiliser -- so it is not the best crop for regions that will get drier. Drought-resistant sorghum might be a better choice for farmers to plant from now on, Lobell suggested. In other areas, crops could be planted earlier than normal to avoid heat-related losses in summer.
"Innovations in policy are needed -- not in technology," said Geoff Tansey, a food policy researcher, writer and editor of a number of books on food policy, including the forthcoming "The Future Control of Food".
With climate change, the best strategy for agriculture is diversity not monocultures, says Tansey, who has worked in many parts of Africa. And by diversity he means not only diversity of crops but of information and knowledge, approaches to farming and diversity of income.
Much of the current agricultural research has been privatised and produces only products that can be patented and sold. There has been a major shift in the past two decades away from public research in agriculture, he warns. The most effective improvements needed to adapt to climate change could be as simple as finding ways for farmers to share their knowledge with each other or by increasing organic matter in soils with manures and crop residues.
Around the world, soils are in decline, largely because of the focus on increasing crop yields. Agriculture depends on using solar energy from the sun to recycle nutrients from the soils into crops that we eat. However, if the nutrients removed from the soils are not replaced, soils become depleted. Recent research has found that chemical fertilisers do not replace these nutrients but rather mask declining soil quality.
See report in Science Magazine 01/02/2008
Prioritizing Climate Change Adaptation Needs for Food Security in 2030
David B. Lobell, Marshall B. Burke, Claudia Tebaldi, Michael D. Mastrandrea, Walter P. Falcon, Rosamond L. Naylor
IPS News 01/02/08 CLIMATE CHANGE: Africa, South Asia Could Face Famines
International Herald Tribune
AFP 08/02/2008 Converting land for biofuel worsens global warming: study