Regional variations in potential groundwater recharge from spring barley crop fields in the UK under projected climate change

This study assessed the variations in the impacts of climate change on potential groundwater recharge from barley crop fields in fourteen UK administrative regions. Future climate data, based on the high, medium and low emissions scenarios (or HES, MES, and LES, respectively), were obtained from the UK Climate Projections 2009 (UKCP09) using the weather generator embedded therein. These were used, together with soil, field and calibrated data of the barley genotype Westminster, to simulate potential groundwater recharge in barley crop fields for the 2030s, 2040s, and 2050s. The results show significant variations in potential groundwater recharge for the regions and the emissions scenarios but not the time slices. There was no interaction effect between time and emissions scenarios. For all emissions scenarios, time slices and regions, the largest reduction and increase in potential groundwater recharge over baseline values were 38% and 41%, respectively. East Midlands had the largest reductions for all time slices and emissions scenarios while Southwest Scotland, Northwest Scotland, Northern Ireland and Wales had the largest increase in potential recharge over baseline values. Generally, reductions were prevalent in the south and the eastern regions of England. Reductions were also highest under HES and lowest under the LES. In the 2030, the largest reductions were 37 mm (HES), 29 mm (MES), and 16 mm (LES). In the 2050 the largest reductions were 31 mm (HES), 27 mm (MES), and 19 mm (LES). It is concluded that the regional variations in potential recharge in arable crop fields during the spring-summer season can be a useful input in adaptation planning that integrates agriculture and water resources management in response to flood and drought risks, and water-food security needs.