Authors: Jonathan Winter*, Dartmouth College, Jose R. Lopez, University of Minnesota, Joshua Elliott, University of Chicago, Alex C. Ruane, NASA Goddard Institute for Space Studies, Cheryl Porter, University of Florida, Gerrit Hoogenboom, University of Florida, Martha Anderson, USDA Agricultural Research Service, Christopher Hain, NASA Marshall Space Flight Center
Topics: Agricultural Geography, Water Resources and Hydrology, Climatology and Meteorology
Keywords: Agriculture, Irrigation, Sustainability, Groundwater, United States
Session Type: Virtual Paper
Start / End Time: 8:00 AM / 9:15 AM
Room: Virtual 46
Presentation File: No File Uploaded
Irrigated farms account for 67% of total groundwater extraction in the United States and $118.5 billion of US agricultural production. However, the current rate of groundwater extraction is unsustainable, especially given historical and projected increases in agricultural water demand. Process-based crop models are able to assess the response of agricultural production to reduced water availability. However, irrigated agricultural projections that directly simulate the impacts of water supply on yield are few, and typically have simplistic representations of crop growth and irrigation such as unlimited water supply and fixed seasonal irrigation rules.
Here, we integrate a gridded crop model with satellite observations and water survey data to assess the effects of sustainable groundwater withdrawals on US agricultural production. Using the most optimistic assumptions for groundwater extraction, we find that sustainable groundwater use will decrease US irrigated production of maize, soybean, and winter wheat by 20%, 6%, and 25%, respectively. Using more conservative assumptions of groundwater availability, US irrigated production of maize, soybean, and winter wheat decrease by 45%, 37%, and 36%, respectively. These results demonstrate the vulnerability of US agricultural production to unsustainable groundwater pumping, highlighting the difficulty of expanding or even maintaining food production in the face of climate change, population growth, and shifting dietary demands.