Climate change may have more of an impact on agriculture than anyone expected. A new study shows that researchers have bene overlooking how two key human responses to climate will impact food production in the future.
In this latest study, the researchers focused on an emerging global breadbasket that as of 2013 supplied 10 percent of the world's soybeans. The Brazilian state of Mato Gross has quickly become an important locale for agriculture. In order to look at this region more closely, the researchers used variations in temperature and precipitation across the state over an 8-year period in order to estimate the sensitivity of the region's agricultural production to climate change.
The researchers found that if the patterns from 2002 to 2008 hold in the future, an increase in average temperature in Mato Grosso of just 1 degree Celsius will lead to a 9 to 13 percent reduction in overall production of soy and corn. This is worrisome given that temperatures are expected to rise by as much as 2 degrees by midcentury under plausible greenhouse gas emissions scenarios.
The study's broader implications stem from the mechanisms behind the changes in agricultural output. Most studies only look at the extent to which climate shocks affect crop yield. In this case, though, the researchers factored in more.
"If you look at yields alone, you're not looking at all of the information because there are economic and social changes going on as well," said Leah VanWey, one of the study's senior authors. "You're not taking into account farmers' reactions to climate shocks."
For example, farmers may reaction to decreasing yields by putting less land area into production because it's simply not profitable. Farmers may also vary the number of crops they plant in a growing season.
In the end, the researchers found that temperature increases of 1 degree Celsius were associated with decreases in total crop area and double cropping. These decreases accounted for 70 percent of the overall loss in production found. Only the remaining 30 percent was attributable to crop yield.
The results suggest that traditional studies may be underestimating the magnitude of the link between climate change and agricultural production. This is especially important to note moving forward.
