Over the last few decades, global warming has hindered the world's food production causing prices to rise, new research reveals.
The study, which NewScientist says is the first "to demonstrate a link between global crop yields and climate change," not only tracks the link between rising temperatures and its effect on food production, but highlights the importance of finding new ways to adapt farming methods to the changing climate.
From The Guardian:
The drop in the productivity of crop plants around the world was not caused by changes in rainfall but was because higher temperatures can cause dehydration, prevent pollination and lead to slowed photosynthesis.
According to David Lobell, a Stanford University scientist and an author of the report, "This is tens of billions of dollars a year in lost productivity because of warming," The Washington Post reports.
To conduct the study, Lobell and his colleagues gathered data dating from 1980 to 2008 for growing regions around the world, including their temperature, rain fall, and crop production. Then, they compared annual yields of four staple crops -- corn, wheat, rice and soy beans -- from every country in the world to what production would have been given precipitation and temperature remained the same since 1980, calculating the predictions with statistical models.
Corn yields were 5.5 percent lower than the predictions showed they would have been if the environmental factors remained constant, and wheat yields were 3.8 percent lower. Wheat production in Russia showed the biggest drop, with yields 15 percent lower than what they could've been. Soy beans and rice were relatively unaffected due to being grown in areas not experiencing as much warming and thriving in higher temperatures, respectively.
"Agriculture as it exists today evolved over 11,000 years of reasonably stable climate, but that climate system is no more," Lester Brown, president of the Earth Policy Institute, told The Guardian.
Not everyone agrees with the findings. Ken Cassman, a professor of systems agronomy at the University of Nebraska, told The Washington Post, "It's not clear how well these analyses are capturing how well farmers can respond, and have been responding, to changing temperatures." Kevin Trenberth of the National Center for Atmospheric Research in Colorado told NewScientist that the results were undermined by using a purely statistical model.
Food prices have reached a record high this year, fueling unrest in regions like North Africa and the Middle East. A recent study presented at 2010's UN climate summit in Cancun predicted that global warming could double grain prices by 2050 and leave millions more malnourished.
This latest research, "Climate Trends and Global Crop Production Since 1980," was published in Thursday's issue of the journal Science.