By 2050, a number of U.S. water basins will begin to experience water shortages if there is no action to reduce greenhouse gases, says a team of MIT researchers. The study says several basins, particularly in the Southwest, will see their existing water shortages become “severely accentuated,” says the MIT study, published in the journal Earth’s Future.
The Southwest is projected to receive less rainfall by mid-century, meaning less runoff that can be used for irrigation. Cotton yields would drop to 10 percent of what would be expected with optimal irrigation supplies, says the study. In the Great Basin in the Northwest, water shortages “will lead to large reductions in irrigated forage, such as hay, grasses, and other crops grown to feed livestock.” At the same time, sorghum and soybean crops would benefit from larger water supplies in the southern Plains.
In a release, MIT notes that the basins that will be the most affected generally do not supply the largest areas of irrigated cropland. “It may not matter too much for the total crop production of the United States, but if you’re a farmer in that particular region that’s going to be impacted, that matters to you,” says Erwan Monier, co-author of the study. “What we want to do is provide useful information that either farmers or land investors can use to look into the future and make decisions on where is the right region to expand irrigated agriculture, and where is it more risky.”