Climate change could increase the risk of a major slowdown in crop production over the next 20 years.
Researchers from Stanford University and the National Center for Atmospheric Research (NCAR) suggest the odds of a reduction in corn and wheat production is 20 times higher than it would be without global warming, although the chances are still slim. The study was published in this month's edition of Environmental Research Letters.
"I'm often asked whether climate change will threaten food supply, as if it's a simple yes or no answer," Stanford professor David Lobell said. "The truth is that over a 10- or 20-year period, it depends largely on how fast the Earth warms, and we can't predict the pace of warming very precisely. So the best we can do is try to determine the odds."
The researchers used computer models on global warming and data on weather and crops to calculate the chances that climate change would have a negative effect of 10 percent on wheat and corn crops in the near future. The team found the chance of natural climate shifts affecting crop production was only about one in 200, but that number jumped from one in 10 for corn and one in 20 for wheat when global warming was taken into account.
The U.N. Food and Agriculture Organization predicted global production of major crops will increase by 13 percent through the year 2030, but demand for these goods is also rapidly rising. The team looked at how climate change will affect the ability of these crops to satisfy the world's needs for food and biofuels.
"Although further study may prove otherwise we do not anticipate adaptation being fast enough to significantly alter the near-term risks estimated in this paper," the researchers wrote.
"We can't predict whether a major slowdown in crop growth will actually happen, and the odds are still fairly low," said NCAR scientist Claudia Tebaldi, a co-author of the study. "But climate change has increased the odds to the point that organizations concerned with food security or global stability need to be aware of this risk."
