HR: 16:30h
AN: H14E-03 INVITED    [Abstracts]
TI: Sources of uncertainty in climate change impacts on groundwater recharge
AU: * Holman, I P
EM: i.holman@cranfield.ac.uk
AF: Cranfield Univesity, Department of Natural Resources Cranfield Univesity, Cranfield, Bed MK43 0AL, United Kingdom
AB: This paper assesses the significance of the many sources of uncertainty in future groundwater recharge estimation, based on lessons learnt from an integrated approach to assessing the regional impacts of climate and socio-economic change on groundwater recharge in East Anglia, UK. Many factors affect simulations of future groundwater recharge including changed precipitation and temperature regimes, coastal flooding, urbanization, woodland establishment, and changes in cropping, rotations and management practices. Stochastic modelling of potential recharge showed median annual recharge decreasing under a High emissions future from 75 mm (1961-90) to 56 mm in the 2020s and 45 mm in the 2050s. However, the median values for individual simulations ranged from 46-75 mm (2020s) and 30-71 mm (2050s) highlighting a decreasing but uncertain trend. The impacts of (and uncertainty in) the climate scenarios are generally regionally more important than those of the socio-economic scenarios. However, locally, the impacts of the socio-economic scenarios can be significant, especially where there are large increases in urbanization, agricultural land cover, bioenergy production, or agricultural management practices. For example, management of soil conditions can increase potential groundwater recharge by around 5 %, but poor management can further reduce potential recharge by up to 15 %. The paper will demonstrate that to focus on the direct impacts of climate change is to neglect the potentially important role of policy, societal values and economic processes in shaping the landscape above aquifers. If the likely consequences of future changes of groundwater recharge, resulting from both climate and socio-economic change, are to be assessed, hydrogeologists must increasingly work with researchers from other disciplines, such as socio-economists, agricultural modellers and soil scientists
DE: 0486 Soils/pedology (1865)
DE: 1807 Climate impacts
DE: 1829 Groundwater hydrology
DE: 1875 Vadose zone
SC: Hydrology [H]
MN: 2007 Fall Meeting