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Climate change projections for the Midwest U.S. indicate a future with increased growing season dryness that will adversely impact crop production sustainability. Systems that capture water for later subirrigation use have potential as a climate adaptation strategy to mitigate this increased crop water stress. Three such systems were operated in northwest Ohio from 1996 to 2008, and they exhibited substantial crop yield benefits, especially in dry growing seasons, but also to a lesser extent in near normal or wet growing seasons. The goal of this research was to estimate the increase in crop yield benefits of water capture and subirrigation systems that can be expected under projcted 2041–2070 climate conditions in northwest Ohio. Historical subirrigated field crop yield differences with fields having free drainage only, relative to growing season dryness/wetness, were used to determine future northwest Ohio subirrigated field crop yield increases, based on the modeled climate for 2041–2070. Climate records for 2041–2070 were projected using three bias corrected model combinations, CRCM+CGCM3, RCM3+GFDL, and MM5I+HadCM3. Growing season dryness/wetness was classified based on the difference between rainfall and the crop adjusted potential evapotranspiration using the 1984–2013 climate record at the three system locations. Projected 2041–2070 growing season precipitation varied substantially between the three model combinations; however, all three indicated increased growing season dryness due to rising temperature and solar radiation. The overall subirrigated field corn yield increase rose to an estimated 27.5%–30.0% in 2041–2070 from 20.5% in 1996–2008, while the subirrigated field soybean yield increase improved from 12.2% in 1996–2008 to 19.8%–21.5% for 2041–2070. Consequently, as growing season drought becomes more frequent, the crop yield benefits with water capture and subirrigation systems will improve, and these systems therefore provide a viable climate adaptation strategy for agricultural production.

Nebraska is situated at the intersection of the northern and southern Great Plains, exhibiting a dramatic longitudinal gradient for precipitation and humidity, and benefiting from groundwater resources. The continental climate is highly variable temporally both for temperature and precipitation. Our assessment of long-term meteorological observations shows that over the last century the annual average temperature in Nebraska has warmed approximately 0.6°C, which is similar to the increase in the global average temperature over the same time period. Furthermore, we found minimum temperatures have warmed more than maximum temperatures, and winter and spring show the strongest warming. We found no significant long-term trend in annual precipitation, but seasonal variations exist, namely with wetter springs and falls, and drier winters and summers. The number of days having temperature extremes (both hot and cold) has decreased over time. We found an overall increase in growing season length.

Agriculture in the Great Lakes region has benefited from precipitation patterns that are fairly regular throughout the year. The beneficial climate, coupled with soils that generally have high water holding abilities, has allowed agriculture in the region to become highly productive and a substantial contributor to the region’s economy. However, predicted shifts in temperature and precipitation patterns towards warmer and wetter winter and spring months, a greater frequency of intense storms throughout the year, and more severe and longer droughts in the summer suggest the potential for decreased crop yields in the future unless ways are found to provide additional water to crops during growing season drought, while also being able to quickly remove excess soil water when conditions are wet.