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By Brian Bienkowski, The Daily Climate
Climate change, and its impacts on extreme weather and temperature swings, is projected to reduce global production of corn, wheat, rice and soybeans by 23 percent in the 2050s, according to a new analysis.
Corn fields.
Credit: Andrew Seaman/flickr
The study, which examined price and production of those four major crops from 1961 to 2013, also warns that by the 2030s output could be cut by 9 percent.
The findings come as researchers and world leaders continue to warn that food security will become an increasingly difficult problem to tackle in the face of rising temperatures and weather extremes, combining with increasing populations, and volatile food prices.
The negative impacts of climate change to farming were pretty much across the board in the new analysis. There were small production gains projected for Russia, Turkey and Ukraine in the 2030s, but by the 2050s, the models “are negative and more pronounced for all countries,” the researchers wrote in the study published this month in the journal Economics of Disasters and Climate Change.
Lead author, Mekbib Haile, a senior researcher at the Center for Development Research, University of Bonn, said that an increase in average temperatures during the growing season isn’t projected to have much impact on the staple crops. But this is only true until that increase hits a certain “tipping point”, he said, which is about 89 degree Fahrenheit for these crops.
“Rising temperature at the two extremes — minimum temperature in the case of rice and maximum temperature in the case of corn — are detrimental to production of these crops,” he said.
In addition to temperature, extreme weather — including droughts and excessive rainfall — was predicted to slow production.
Haile’s study is one of two major studies this month reporting big impacts to major crops in the future. Just this week UC Davis researchers released a study in the Environmental Research Letters journal reporting that by the end of the century climate change is likely to cause France’s winter wheat yields to decrease 21 percent, winter barley yields to decrease by 17 percent and spring barley to decrease by about to 33 percent.
The reports are concerning as wheat and rice are two of the top calorie sources in the world, and decreases in such staple crops could add to the current total of 795 million people suffering from hunger and more than 2 billion people with nutrient deficiencies.
And there will be more mouths to feed as the world population is projected to grow by more than 2 billion, reaching about 9.7 billion people, by 2050.
Haile said some farming changes — such as improved irrigation or genetically modified crops, or more sustainable practices like increased organic production or tilling less — could help offset some climate-induced losses.
Agricultural crop production more than tripled between 1960 and 2015, according to the Food and Agriculture Organization of the United Nations’ new report on the future of food and agriculture.
But farms will have to produce about 50 percent more food in 2050, and in some areas such as Sub-Saharan Africa, output will have to more than double to meet increased demand from growing populations.
“Despite overall improvements in agricultural efficiency, yield increases are slowing due to climate change and so maintaining the historic pace of production increases may be difficult,” according to the FAO report.
Reprinted with permission from The Daily Climate.
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