Climate change to deplete some US water basins, reduce irrigated crop yields.
A new study by MIT climate scientists, economists, and agriculture experts finds that certain hotspots in the country will experience severe reductions in crop yields by 2050, due to climate change’s impact on irrigation.
The most adversely affected region, according to the researchers, will be the Southwest.
Production of cotton, the primary irrigated crop in the Southwest and in southern Arizona in particular, will drop to less than 10 percent of the crop yield under optimal irrigation conditions, the study projects.
“A more integrated world” While many researchers have investigated the effects of climate change on crop yields, Blanc’s study is one of the first to consider how a changing climate may shape the availability and distribution of water basins on which irrigated crops depend.
“Most modeling studies that look at the impact of climate change on crop yield and the fate of agriculture don’t take into account whether the water available for irrigation will change,” Monier says.
They then used a crop model to simulate daily water requirements for various crops, driven by the researchers’ modeled projections of precipitation and temperature, and compared these requirements with the amount of water predicted to be available for irrigation in a particular basin through the year 2050.
“The biggest finding is that it really makes a difference in specific regions, whether you take into account how irrigation availability will change in the future and how that will impact yields,” Monier says.
For example, though climate change will significantly reduce cotton production in the Southwest, the bulk of the country’s cotton production does not occur in this region.
We also want to make clear that climate mitigation is better for U.S. irrigated agriculture than not doing anything.” A climate-changing landscape Under the same business-as-usual scenario, the researchers projected higher yields for irrigated crops such as wheat, soybean, and sorghum.