Grusson, Youen
- Department of Soil and Environment, Swedish University of Agricultural Sciences
- Laval University
- University of Toulouse
Abstract
Climate change is suspected to impact water circulation within the hydrological cycle at catchment scale. A SWAT model approach to assess the evolution of the many hydrological components of the Garonne catchment (Southern France) is deployed in this study. Performance over the calibration period (2000-2010) are satisfactory, with Nash-Sutcliffe ranging from 0.55 to 0.94 or R-2 from 0.86 to 0.98. Similar performance values are obtained in validation (1962-2000). Water cycle is first analyzed based on past observed climatic data (1962-2010) to understand its variations and geographical spread. Comparison is then conducted against the different trends obtained from a climate ensemble over 2010-2050. Results show a strong impact on green water, such as a reduction of the soil water content (SWC) and a substantial increase in evapotranspiration (ET) in winter. In summer, however, some part of the watershed faces lower ET fluxes because of a lack of SWC to answer the evapotranspiratory demand, highlighting possible future deficits of green water stocks. Blue water fluxes are found significantly decreasing during summer, when in winter, discharge in the higher part of the watershed is found increasing because of a lower snow stock associated to an increase of liquid precipitation, benefiting surface runoff.
Keywords
water cycle; climate change; SWAT modelling; coevolution of water resources; blue and green water
Published in
Water
2018, volume: 10, number: 12, article number: 1870
Publisher: MDPI
SLU Authors
Global goals (SDG)
SDG6 Clean water and sanitation
UKÄ Subject classification
Climate Science
Oceanography, Hydrology, Water Resources
Publication identifier
- DOI: https://doi.org/10.3390/w10121870
Permanent link to this page (URI)
https://res.slu.se/id/publ/98217