DOI: 10.5194/hess-19-1225-2015
Scopus记录号: 2-s2.0-84929312819
论文题名: Attribution of high resolution streamflow trends in Western Austria - An approach based on climate and discharge station data
作者: Kormann C ; , Francke T ; , Renner M ; , Bronstert A
刊名: Hydrology and Earth System Sciences
ISSN: 10275606
出版年: 2015
卷: 19, 期: 3 起始页码: 1225
结束页码: 1245
语种: 英语
Scopus关键词: Runoff
; Snow
; Watersheds
; High resolution
; Hydrological condition
; Melting glaciers
; Rising temperatures
; Snow accumulation
; Spatial patterns
; Statistical modeling
; Streamflow changes
; Stream flow
; alpine environment
; altitude
; discharge
; flow pattern
; freezing
; hydrological modeling
; spatial variation
; streamflow
; Austria
英文摘要: The results of streamflow trend studies are often characterized by mostly insignificant trends and inexplicable spatial patterns. In our study region, Western Austria, this applies especially for trends of annually averaged runoff. However, analysing the altitudinal aspect, we found that there is a trend gradient from higher-altitude to lower-altitude stations, i.e. a pattern of mostly positive annual trends at higher stations and negative ones at lower stations. At mid-altitudes, the trends are mostly insignificant. Here we hypothesize that the streamflow trends are caused by the following two main processes: on the one hand, melting glaciers produce excess runoff at higher-altitude watersheds. On the other hand, rising temperatures potentially alter hydrological conditions in terms of less snowfall, higher infiltration, enhanced evapotranspiration, etc., which in turn results in decreasing streamflow trends at lower-altitude watersheds. However, these patterns are masked at mid-altitudes because the resulting positive and negative trends balance each other. To support these hypotheses, we attempted to attribute the detected trends to specific causes. For this purpose, we analysed trends of filtered daily streamflow data, as the causes for these changes might be restricted to a smaller temporal scale than the annual one. This allowed for the explicit determination of the exact days of year (DOYs) when certain streamflow trends emerge, which were then linked with the corresponding DOYs of the trends and characteristic dates of other observed variables, e.g. the average DOY when temperature crosses the freezing point in spring. Based on these analyses, an empirical statistical model was derived that was able to simulate daily streamflow trends sufficiently well. Analyses of subdaily streamflow changes provided additional insights. Finally, the present study supports many modelling approaches in the literature which found out that the main drivers of alpine streamflow changes are increased glacial melt, earlier snowmelt and lower snow accumulation in wintertime. © Author(s) 2015. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/78580
Appears in Collections: 气候变化事实与影响
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作者单位: Institute of Earth and Environmental Science, University of Potsdam, Potsdam, Germany; Biospheric Theory and Modeling, Max Planck Institute for Biogeochemistry, Jena, Germany
Recommended Citation:
Kormann C,, Francke T,, Renner M,et al. Attribution of high resolution streamflow trends in Western Austria - An approach based on climate and discharge station data[J]. Hydrology and Earth System Sciences,2015-01-01,19(3)