Volume 536, 1 December 2015, Pages 12–24
Highlights
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- A cantonal vision of where and when water tensions are likely to occur is provided.
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- Hydro-climatic and socio-economic changes are assessed by the mid-21st century.
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- Water shortage episodes could become more frequent in western Switzerland.
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- The Lake Geneva region should experience severe water stress during summer.
Abstract
Recent
observed hydro-climatic changes in mountainous areas are of concern as
they may directly affect capacity to fulfill water needs. The canton of
Vaud in Western Switzerland is an example of such a region as it has
experienced water shortage episodes during the past decade. Based on an
integrated modeling framework, this study explores how hydro-climatic
conditions and water needs could evolve in mountain environments and
assesses their potential impacts on water stress by the 2060 horizon.
Flows were simulated based on a daily semi-distributed hydrological
model. Future changes were derived from Swiss climate scenarios based on
two regional climate models. Regarding water needs, the authorities of
the canton of Vaud provided a population growth scenario while
irrigation and livestock trends followed a business-as-usual scenario.
Currently, the canton of Vaud experiences moderate water stress from
June to August, except in its Alpine area where no stress is noted. In
the 2060 horizon, water needs could exceed 80% of the rivers' available
resources in low- to mid-altitude environments in mid-summer. This
arises from the combination of drier and warmer climate that leads to
longer and more severe low flows, and increasing urban (+ 40%) and
irrigation (+ 25%) water needs. Highlighting regional differences
supports the development of sustainable development pathways to reduce
water tensions. Based on a quantitative assessment, this study also
calls for broader impact studies including water quality issues.
Graphical abstract
Keywords
- Climate scenarios;
- Anthropogenic changes;
- Water stress;
- Regional overview;
- Mountain environment;
- Western Switzerland
Copyright © 2015 Elsevier B.V. All rights reserved.
