Farmers fed up with climate change-induced heat waves, droughts and flooding may one day get to reap rewards of a unique U.S. government experiment that aims to understand how crops will adapt to even harsher conditions.
In a field in Maricopa, Arizona, about 35 miles south of Phoenix, a group of researchers at the (USDA) are simulating high temperatures anticipated to occur in 2050, using infrared heaters suspended above wheat plants.
The results of these experiments, they say, might tamp down future food crises by helping growers and ranchers manage their crops and livestock as temperatures change.
For many, relief can't come too soon, as climate-related impacts are already affecting food supplies. The spring wheat crop in North Dakota, for instance, is being threatened by potential heavy rain and flooding, and last summer's drought and heat wave in Russia damaged crops that contributed to higher global wheat prices.
"No one knows how changing conditions will affect yields in the decades ahead, and we're trying to give growers an idea about what they might expect," said Bruce Kimball, a retired soil scientist with the , a project of the USDA's Agriculture Research Service (ARS).
Kimball developed the T-FACE, or temperature free-air controlled enhancement, apparatus that raises the temperature of experiment crops in open fields.
The device is being shared with scientists working on cropland in Australia, China and Mexico and on native range lands in Colorado.
The were published on February 24 in the journal Global Change Biology. Kimball and the other ARS scientists say their preliminary results closely resemble what they had expected after examining the computer model predictions of global warming effects on food crops.
'A Little Global Warming' Has 'Dramatic Effect'
Kimball, together with ARS plant physiologists Gerald Wall and Jeffrey Whit, and Michael Ottman, an agronomist from the University of Arizona, used six 1,000-watt infrared heaters suspended above the plants in a hexagonal pattern, which allowed them to boost the temperature of crops in open fields.
Typically, Arizona wheat is planted in mid-winter and harvested in late May. Temperatures can range from below freezing in winter to above 100 degrees Fahrenheit in May, Kimball told SolveClimate News.
As part of the experiment, the team planted wheat every six weeks in separate plots between March 2007 and May 2009. The researchers applied heat to six of the 15 plantings so that the temperatures rose by 2.7 degrees Fahrenheit in the daytime and five to six degrees Fahrenheit at night.
Not surprisingly, the warmer temperatures helped the wheat grow faster, allowing the crop to be harvested one week earlier than normal, Kimball said. Also expected was that wheat planted six months earlier, in spring rather than mid-winter, suffered.
There was at least one surprise, however, the scientists noted.
Wheat planted three months earlier in September grew for a longer period of time — enough to allow the crop to remain undamaged when frost began to dust the fields around the last week of December.
"The heaters actually saved the wheat that was planted early," Kimball said. "So you can say a little bit of global warming can really have a dramatic effect on wheat yields," Kimball said.
The findings imply that wheat grown in warm-weather climates resembling the Maricopa region might be able to survive a seven-month growing season, instead of the typical five-month season, Kimball said.
T-FACE Experiments Pricey but 'Must Be Done'
David Lobell, an assistant professor of environmental earth system science at Stanford University, said that employing T-FACE in the field is unique and very expensive, "but it must be done if you are going to find out how to adapt."