DOI: 10.5194/hess-23-2983-2019
论文题名: Monitoring snowpack outflow volumes and their isotopic composition to better understand streamflow generation during rain-on-snow events
作者: Rücker A. ; Boss S. ; Kirchner J.W. ; Von Freyberg J.
刊名: Hydrology and Earth System Sciences
ISSN: 1027-5606
出版年: 2019
卷: 23, 期: 7 起始页码: 2983
结束页码: 3005
语种: 英语
Scopus关键词: Catchments
; Floods
; Forestry
; Isotopes
; Lysimeters
; Mixing
; Rain
; Runoff
; Sea level
; Snow melting systems
; Soil surveys
; Stream flow
; Topography
; Alpine catchments
; End member mixing
; Hydrograph separation
; Hydrological models
; Isotopic composition
; Process understanding
; Snow accumulation
; Streamflow generations
; Snow
; catchment
; environmental monitoring
; flood
; hydrological modeling
; isotopic composition
; mountain region
; rainwater
; snowmelt
; snowpack
; streamflow
; volume
英文摘要: Rain-on-snow (ROS) events in mountainous catchments can cause enhanced snowmelt, leading to an increased risk of destructive winter floods. However, due to differences in topography and forest cover, the generation of snowpack outflow volumes and their contribution to streamflow are spatially and temporally variable during ROS events. In order to adequately predict such flood events with hydrological models, an enhanced process understanding of the contribution of rainwater and snowmelt to stream water is needed. In this study, we monitored and sampled snowpack outflow with fully automated snowmelt lysimeter systems installed at three different elevations in a pre-Alpine catchment in central Switzerland. We measured snowpack outflow volumes during the winters of 2017 and 2018, as well as snowpack outflow isotopic compositions in winter 2017. Snowpack outflow volumes were highly variable in time and space, reflecting differences in snow accumulation and melt. In winter 2017, around 815 mm of snowpack outflow occurred at our reference site (grassland 1220 m a.s.l.-metres above sea level), whereas snowpack outflow was 16 % less at the nearby forest site (1185 m a.s.l.), and 62 % greater at another grassland site located 200 m higher (1420 m a.s.l.). A detailed analysis of 10 ROS events showed that the differences in snowpack outflow volumes could be explained mainly by rainfall volumes and initial snow depths. The isotope signals of snowpack outflow were more damped than those of incoming rainwater at all three sites, with the most damped signal at the highest elevation site because its snowpack was the thickest and the residence times of liquid water in its snowpack were the longest, thus enhancing isotopic mixing in the snowpack. The contribution of snowpack outflow to streamflow, estimated with an isotopebased two-component end-member mixing model, differed substantially among the three lysimeter sites (i.e. between 7 ± 4 and 91 ± 21 %). Because the vegetation in our study catchment is a mixture of grassland and forest, with elevations ranging from 1000 to 1500 m a.s.l., our site-specific hydrograph separation estimates can only provide a range of snowpack outflow contributions to discharge from different parts of the study area. Thus, the catchment-average contribution of snowpack outflow to stream discharge is likely to lie between the end-member mixing estimates derived from the three site-specific data sets. This information may be useful for improving hydrological models in snow-dominated catchments. © 2019 Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/163097
Appears in Collections: 气候变化与战略
There are no files associated with this item.
作者单位: Rücker, A., Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf, 8903, Switzerland, Department of Environmental System Science, ETH Zürich, Universitätsstrasse 16, Zurich, 8092, Switzerland; Boss, S., Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf, 8903, Switzerland; Kirchner, J.W., Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf, 8903, Switzerland, Department of Environmental System Science, ETH Zürich, Universitätsstrasse 16, Zurich, 8092, Switzerland; Von Freyberg, J., Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Zürcherstrasse 111, Birmensdorf, 8903, Switzerland, Department of Environmental System Science, ETH Zürich, Universitätsstrasse 16, Zurich, 8092, Switzerland
Recommended Citation:
Rücker A.,Boss S.,Kirchner J.W.,et al. Monitoring snowpack outflow volumes and their isotopic composition to better understand streamflow generation during rain-on-snow events[J]. Hydrology and Earth System Sciences,2019-01-01,23(7)