By Elizabeth Zach, staff writer
By mid-century, climate change effects on irrigation could diminish crop yields around the country. Nowhere else would this be more dramatic, according to a new study, than in the American Southwest.
Climate scientists, economists and agriculture analysts at the Massachusetts Institute of Technology report their findings in the journal Earth Future, and note that less rainfall in the area translates into less runoff into water basins that irrigate fields such as cotton in southern Arizona and maize in Utah. They also observe that in the Pacific Northwest, hay, grasses and other crops grown to feed livestock will be affected.
Although other studies have examined climate change effects on crop yields, this current report is among the first to look at how a changing climate affects water basins’ availability and distribution for irrigated crops. The researchers studied 99 major river basins in the United States, and specifically looked at how greenhouse gas emissions and other pollutants impact freshwater and ocean systems.
“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,” Erwan Monier, one of the principal research scientists said. “We’re looking at a more integrated world, and how all these interactions will drive changes in irrigation.”