How does climate change affect mesoscale catchments in Switzerland? – a framework for a comprehensive assessment
Within the framework of this study we identify mesoscale catchments in Switzerland that exhibit sensitivity towards a change in climate with a focus on alterations of the water balance and peak flow conditions. For this study, the hydrological modelling system PREVAH is used, which is a semi-distrib...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2010-09-01
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| Series: | Advances in Geosciences |
| Online Access: | http://www.adv-geosci.net/27/111/2010/adgeo-27-111-2010.pdf |
| _version_ | 1818292534550462464 |
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| author | N. Köplin D. Viviroli B. Schädler R. Weingartner |
| author_facet | N. Köplin D. Viviroli B. Schädler R. Weingartner |
| author_sort | N. Köplin |
| collection | DOAJ |
| description | Within the framework of this study we identify mesoscale catchments in
Switzerland that exhibit sensitivity towards a change in climate with a focus
on alterations of the water balance and peak flow conditions. For this study,
the hydrological modelling system PREVAH is used, which is a semi-distributed
and conceptual yet process-oriented model forced with hourly meteorological
input on basis of a spatial resolution of 500×500 m<sup>2</sup>. We
calibrate the model where measured discharge records are available and
transfer the calibrated model parameters to ungauged catchments through
regionalisation, to arrive at a comprehensive set of model parameters for the
entire area of Switzerland. To assess future changes, we apply an extensive
set of 16 Regional Climate Models (RCMs) to the catchments. The RCM data are
downscaled to a dense network of meteorological stations for the period from
2021 to 2050 using the Delta Change Approach. This downscaling method
incorporates a bias correction of the RCM output and provides change rates
and values for precipitation and temperature.
<br><br>
In the present paper we describe the application of a calibration and
regionalisation procedure developed previously for Northern Alpine catchments
to Southern catchments. The necessity to differentiate between a Northern and
a Southern Alpine region, with their distinct climatologic and
physiogeographic features, has proved true as the calibrated parameter sets
show systematic differences between those regions, e.g. for the runoff
forming parameters percolation rate (PERC) or storage time for quick runoff
(KOH). For the Southern Alpine area, we calibrated two thirds of the
available catchments, i.e. 23 out of 36, successfully for standard and flood
conditions according to a combined model score of a linear and logarithmic
Nash-Sutcliffe-Efficiency (NSE, NSE<sub>ln</sub>) and a mean annual volumetric
deviation (VD<sub>a</sub>). The rate of successfully calibrated catchments is
rather small in comparison with the results for the Northern Alpine
catchments, where 140 out of 159 calibrations have been successful, and the
distribution of the Southern catchments is more irregular. However, as the
median NSE and NSE<sub>ln</sub> as well as the range of VD<sub>a</sub> show an
overall good model fit, a successful regionalisation may be expected. Next
steps are the regionalisation of the Southern Alpine model parameters and the
application of climate scenarios to the complete set of catchments,
i.e. about 200 Swiss mesoscale catchments with an average area of
150 km<sup>2</sup>. Thus we can identify process-based relationships between climate
sensitivity and catchment characteristics and provide quantitative
information on future water balance and peak flow conditions of Swiss
mesoscale catchments. |
| first_indexed | 2024-12-13T03:01:29Z |
| format | Article |
| id | doaj.art-74b2fdd0e8154fee970129b67fe96e40 |
| institution | Directory Open Access Journal |
| issn | 1680-7340 1680-7359 |
| language | English |
| last_indexed | 2024-12-13T03:01:29Z |
| publishDate | 2010-09-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Advances in Geosciences |
| spelling | doaj.art-74b2fdd0e8154fee970129b67fe96e402022-12-22T00:01:49ZengCopernicus PublicationsAdvances in Geosciences1680-73401680-73592010-09-012711111910.5194/adgeo-27-111-2010How does climate change affect mesoscale catchments in Switzerland? – a framework for a comprehensive assessmentN. Köplin0D. Viviroli1B. Schädler2R. Weingartner3Institute of Geography, University of Bern, Bern, SwitzerlandInstitute of Geography, University of Bern, Bern, SwitzerlandInstitute of Geography, University of Bern, Bern, SwitzerlandInstitute of Geography, University of Bern, Bern, SwitzerlandWithin the framework of this study we identify mesoscale catchments in Switzerland that exhibit sensitivity towards a change in climate with a focus on alterations of the water balance and peak flow conditions. For this study, the hydrological modelling system PREVAH is used, which is a semi-distributed and conceptual yet process-oriented model forced with hourly meteorological input on basis of a spatial resolution of 500×500 m<sup>2</sup>. We calibrate the model where measured discharge records are available and transfer the calibrated model parameters to ungauged catchments through regionalisation, to arrive at a comprehensive set of model parameters for the entire area of Switzerland. To assess future changes, we apply an extensive set of 16 Regional Climate Models (RCMs) to the catchments. The RCM data are downscaled to a dense network of meteorological stations for the period from 2021 to 2050 using the Delta Change Approach. This downscaling method incorporates a bias correction of the RCM output and provides change rates and values for precipitation and temperature. <br><br> In the present paper we describe the application of a calibration and regionalisation procedure developed previously for Northern Alpine catchments to Southern catchments. The necessity to differentiate between a Northern and a Southern Alpine region, with their distinct climatologic and physiogeographic features, has proved true as the calibrated parameter sets show systematic differences between those regions, e.g. for the runoff forming parameters percolation rate (PERC) or storage time for quick runoff (KOH). For the Southern Alpine area, we calibrated two thirds of the available catchments, i.e. 23 out of 36, successfully for standard and flood conditions according to a combined model score of a linear and logarithmic Nash-Sutcliffe-Efficiency (NSE, NSE<sub>ln</sub>) and a mean annual volumetric deviation (VD<sub>a</sub>). The rate of successfully calibrated catchments is rather small in comparison with the results for the Northern Alpine catchments, where 140 out of 159 calibrations have been successful, and the distribution of the Southern catchments is more irregular. However, as the median NSE and NSE<sub>ln</sub> as well as the range of VD<sub>a</sub> show an overall good model fit, a successful regionalisation may be expected. Next steps are the regionalisation of the Southern Alpine model parameters and the application of climate scenarios to the complete set of catchments, i.e. about 200 Swiss mesoscale catchments with an average area of 150 km<sup>2</sup>. Thus we can identify process-based relationships between climate sensitivity and catchment characteristics and provide quantitative information on future water balance and peak flow conditions of Swiss mesoscale catchments.http://www.adv-geosci.net/27/111/2010/adgeo-27-111-2010.pdf |
| spellingShingle | N. Köplin D. Viviroli B. Schädler R. Weingartner How does climate change affect mesoscale catchments in Switzerland? – a framework for a comprehensive assessment Advances in Geosciences |
| title | How does climate change affect mesoscale catchments in Switzerland? – a framework for a comprehensive assessment |
| title_full | How does climate change affect mesoscale catchments in Switzerland? – a framework for a comprehensive assessment |
| title_fullStr | How does climate change affect mesoscale catchments in Switzerland? – a framework for a comprehensive assessment |
| title_full_unstemmed | How does climate change affect mesoscale catchments in Switzerland? – a framework for a comprehensive assessment |
| title_short | How does climate change affect mesoscale catchments in Switzerland? – a framework for a comprehensive assessment |
| title_sort | how does climate change affect mesoscale catchments in switzerland a framework for a comprehensive assessment |
| url | http://www.adv-geosci.net/27/111/2010/adgeo-27-111-2010.pdf |
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