By Christina Wright
A new study suggests that we need to look back in time in order to plan accordingly for the future in agriculture and crop production. This study, Climate Trends and Global Crop Production Since 1980, was completed by David Lobell and Justin Costa-Roberts, professors at Stanford University, and Wolfram Schlenker, a professor at Columbia University. It looks at the effects of climate change on global crop production from 1980 to 2008 and finds that climate change and global warming are decreasing crop yields and making the global population more vulnerable to food insecurity. As the world’s population crests 7 billion people, this study shows how increases in temperatures and changes in precipitation have affected crop yields over the past 28 years so we may plan accordingly for the future.
Authors of this recent report say that higher temperatures have increased the price of many crops, including maize. (Photo credit: Cornell University)
The authors looked at the effects of changes in temperature and precipitation in several parts of the world, including the United States and Russia. In their findings the authors determined that a one-degree Celsius rise in temperature could lower crop yields by up to 10 percent, “except in high-latitude countries, where rice in particular gains from warming.” As for precipitation, the authors found that rainfall will “increase crop yields for nearly all crops, up to a point at which further rainfall becomes harmful.”
According to Lobell, who is also a contributing author of State of the World 2011: Innovations that Nourish the Planet, Costa-Roberts, and Schlenker, “global maize production would be roughly 6 percent higher and wheat production would be 4 percent higher if agriculture had not been exposed to climate trends since 1980.” But over the past 28 years, wheat yields in China, France, India, and Russia have all decreased. In recent years, wheat yields in Russia have been down by more than 10 percent. As crop yields have decreased, food prices have increased. The authors estimate that the effects of warmer temperatures on crop yields have increased the global market prices for maize and wheat by roughly 20 percent.
The new study aims to address and answer questions such as, “how have changes already influenced agriculture activities?” and “will agriculture be impacted mainly by rising temperatures, or will changes in precipitation be the main concern?” Their conclusions not only provide insight to climate and agricultural trends in the past 30 years, but they are also relevant for policymakers deciding on how new laws will impact climate change and agricultural production in the future.
What do you think of this new study? Tell us in the comments!
Christina Wright is a research intern with the Nourishing the Planet project.