Future environmental change is expected to modify the global hydrological cycle, with consequences for the regional distribution of freshwater supplies. Regional precipitation projections, however, differ largely between models, making future water resource projections highly uncertain. Using two representative concentration pathways and nine climate models, we estimate 21st century water resources across Australia, employing both a process-based dynamic vegetation model and a simple hydrological framework commonly used in water resource studies to separate the effects of climate and vegetation on water resources. We show surprisingly robust, pathway-independent regional patterns of change in water resources despite large uncertainties in precipitation projections. Increasing plant water use efficiency (due to the changing atmospheric CO2) and reduced green vegetation cover (due to the changing climate) relieve pressure on water resources for the highly populated, humid coastal regions of eastern Australia. By contrast, in semi-arid regions across Australia, runoff declines are amplified by CO2-induced greening, which leads to increased vegetation water use. These findings highlight the importance of including vegetation dynamics in future water resource projections.
Department of Biological Sciences, Macquarie University, North Ryde, New South Wales 2109, Australia;ARC Centre of Excellence for Climate System Science, University of New South Wales, Kensington, New South Wales 2052, Australia;Department of Biological Sciences, Macquarie University, North Ryde, New South Wales 2109, Australia;Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA;Department of Biological Sciences, Macquarie University, North Ryde, New South Wales 2109, Australia;Centre for Past Climate Change and School of Archaeology, Geography and Environmental Sciences (SAGES), University of Reading, Whiteknights, RG6 6 AH, Reading, UK;Centre for Ecology and Hydrology, Maclean building, Crowmarsh Gifford, Wallingford, Oxfordshire, OX10 8BB, UK;Department of Biological Sciences, Macquarie University, North Ryde, New South Wales 2109, Australia;AXA Chair of Biosphere and Climate Impacts, Department of Life Sciences and Grantham Institute—Climate Change and the Environment, Imperial College, Silwood Park Campus, Ascot SL5 7PY, UK
Recommended Citation:
A M Ukkola,T F Keenan,D I Kelley,et al. Vegetation plays an important role in mediating future water resources[J]. Environmental Research Letters,2016-01-01,11(9)