Higher temperatures and more variable rainfall associated with climate change will produce agricultural “winners and losers”, threatening a 20 percent rise in worldwide malnutrition and increasing the need to move food supplies around the globe, leading agricultural scientists said on Wednesday.
Northern countries will likely enjoy boosts in production through 2020 as a result of global warming, while southern regions including East and West Africa and India’s breadbasket will suffer declines, particularly in rain-fed crops, said Andy Jarvis, an agriculture policy expert at the International Centre for Tropical Agriculture, based in Cali, Colombia.
After an average increase through 2020, the global “potential to produce food” could decline by 5 to 10 percent by 2050, Jarvis said.
“The food security challenge facing us as humans is large,” Gerald Nelson, a senior research fellow with the International Food Policy Research Institute in Washington, told a press briefing announcing a $200 million research programme that will seek answers to the growing food security threat.
In particular, between 2050 and 2080, if greenhouse gas emissions are not reduced, “it becomes an almost impossible challenge to deal with the climate change and food security threats facing us”, Nelson said.
These trends will add to the burden of distributing food supplies around the world, with an increasing share of production occurring in regions far from where it is needed, Jarvis said.
The collaboration, which brings together agricultural experts from the Consultative Group on International Agricultural Research (CGIAR) and climate scientists at the Earth System Science Partnership (ESSP), aims to help the world’s poorest farmers maintain agricultural production in the face of climate pressures, reduce poverty by 10 percent by 2050 in “hot spot” regions in Africa and India, and cut the number of malnourished people in those areas by a quarter.
Another objective is to curb emissions associated with agriculture, which produces between 20 percent and 33 percent of global carbon emissions, depending on whether the conversion of forests to farmland is included.
“(The project’s) success will be measured in outcomes, not in scholarly articles,” said Bruce Campbell, CGIAR’s director of the initiative.
ADAPTING CROPS AND ANIMALS
The programme will use an Australian climate model to look at how rising temperatures and rainfall changes will affect 50 major crops worldwide, including some developing world staples such as sorghum, millet and sweet potato as well as wheat, rice and maize.
Early work shows that West Africa, for instance, could see declines in soybean, wheat, potato and sorghum production, but some gains – at least initially – in crops like sugarcane and sweet potato.
In India’s Indo-Gangetic Plain – a major rice and wheat breadbasket that feeds 600 million people – higher temperatures in March, when heads of wheat fill out, are already slashing harvests, Jarvis said. Farmers in the area, who grow both crops, are attempting to ease the problem by bringing the wheat planting season forward. But that shift threatens to interfere with the rice season, which is timed to monsoon rains.
Climate models suggest rain-fed wheat worldwide will see accelerating declines in production – of 2.2 percent by 2020, 4 percent by 2050 and 18.6 percent by 2080 – unless climate change is curbed or effective adaptive measures are put in place, the scientists said.
If crop varieties more tolerant of drought, floods and pests cannot be successfully developed, some societies may need to to switch their staples to maintain food production, although “obviously that’s quite an upheaval for those communities”, Jarvis said.
In other areas, herders may have to swap their sheep and cattle for more drought-tolerant goats and camels, said Philip Thornton, a Nairobi-based senior scientist with the International Livestock Research Institute.
But grazing animals on pastures sown with particular grass species rather than on wild pastureland should allow farmers and herders to curb the methane gas their livestock produce – a big contributor to greenhouse gas levels – and as much as triple milk and meat production, he said.
Scientists working on the new Climate Change, Agriculture and Food Security (CCAFS) initiative said they hope to see a higher profile for agriculture at the upcoming U.N. climate talks in Cancun. Right now, “agriculture is hardly part of the current global policies” for dealing with climate change, said project director Campbell.