Agricultural problems caused by global warming in the next two decades could be most damaging in southern Africa, India and Pakistan, according to researchers who urge action now to avert a wave of hunger.
Many scientists have predicted that climate change could harm agriculture in many places, fuelling hunger and malnutrition. These researchers examined climate predictions and the types of crops grown in various developing regions to figure out which ones would be hit hardest by 2030.
The researchers said the nations of southern Africa - Angola, Botswana, Lesotho, Malawi, Mozambique, Namibia, South Africa, Swaziland, Zambia and Zimbabwe - could lose about 30 percent of their main crop of corn, also known as maize.
Agricultural losses also could be significant in the South Asia region encompassing India, Pakistan, Nepal and Sri Lanka, with a drop-off of at least 5 percent in many regional staples, including millet, maize and rice, the researchers said.
"We still have time to avoid these impacts, but we don't have much time," David Lobell of the Program on Food Security and the Environment at Stanford University in California, who led the research, said in a telephone interview.
"It's certainly our hope not to scare people, but to show them that there is some basis for focusing efforts and trying to get things done in a relatively speedy time frame," Lobell added.
The researchers projected how global warming would affect agriculture in 12 developing regions worldwide, looking at local climate projections and at the sensitivity of key local crops to warming temperatures and rainfall changes. They determined that average temperatures in most of the regions could rise by 1.8 degrees Fahrenheit (1 degree C) by 2030.