Spatio-temporal impact of climate change on the groundwater system

J Dams,P Willems,T Van Daele,E Salvadore,O Batelaan,V Ntegeka

doi:10.5194/hess-16-1517-2012

Abstract

Abstract. Given the importance of groundwater for food production and drinking water supply, but also for the survival of groundwater dependent terrestrial ecosystems (GWDTEs) it is essential to assess the impact of climate change on this freshwater resource. In this paper we study with high temporal and spatial resolution the impact of 28 climate change scenarios on the groundwater system of a lowland catchment in Belgium. Our results show for the scenario period 2070–2101 compared with the reference period 1960–1991, a change in annual groundwater recharge between −20% and +7%. On average annual groundwater recharge decreases 7%. In most scenarios the recharge increases during winter but decreases during summer. The altered recharge patterns cause the groundwater level to decrease significantly from September to January. On average the groundwater level decreases about 7 cm with a standard deviation between the scenarios of 5 cm. Groundwater levels in interfluves and upstream areas are more sensitive to climate change than groundwater levels in the river valley. Groundwater discharge to GWDTEs is expected to decrease during late summer and autumn as much as 10%, though the discharge remains at reference-period level during winter and early spring. As GWDTEs are strongly influenced by temporal dynamics of the groundwater system, close monitoring of groundwater and implementation of adaptive management measures are required to prevent ecological loss.

Highlights

There is little doubt that the ongoing climate change will significantly influence the hydrological cycle worldwide (Kundzewicz et al, 2008; Maxwell and Kollet, 2008)
This paper discusses how climate changes alter the spatiotemporal dynamics of the groundwater system
Most GCMs predict that global warming is likely to amplify drought events over Europe

Summary

Introduction

There is little doubt that the ongoing climate change will significantly influence the hydrological cycle worldwide (Kundzewicz et al, 2008; Maxwell and Kollet, 2008). Current observations show that already at this moment climate changes are influencing hydrological processes in certain areas (Rosenzweig et al, 2007; Kundzewicz and Doll, 2009). As the IPCC predicts that global atmospheric concentrations of greenhouse gases will continue to rise, it is expected that climate change will continue in the future (Solomon et al, 2007). There is an increasing awareness to protect the groundwater resources and to assess the impact of future land-use and climate changes (Solomon et al, 2007; Green et al, 2011)

Results

Discussion

Conclusion