气候变化领域集成服务门户(CCPortal): Monitoring snowpack outflow volumes and their isotopic composition to better understand streamflow generation during rain-on-snow events

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DOI	10.5194/hess-23-2983-2019
	Monitoring snowpack outflow volumes and their isotopic composition to better understand streamflow generation during rain-on-snow events
	Rücker A.; Boss S.; Kirchner J.W.; Von Freyberg J.
发表日期	2019
ISSN	1027-5606
起始页码	2983
结束页码	3005
卷号	23 期号:7
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).
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
来源期刊	Hydrology and Earth System Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/159814
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
推荐引用方式 GB/T 7714	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],2019,23(7).
APA	Rücker A.,Boss S.,Kirchner J.W.,&Von Freyberg J..(2019).Monitoring snowpack outflow volumes and their isotopic composition to better understand streamflow generation during rain-on-snow events.Hydrology and Earth System Sciences,23(7).
MLA	Rücker A.,et al."Monitoring snowpack outflow volumes and their isotopic composition to better understand streamflow generation during rain-on-snow events".Hydrology and Earth System Sciences 23.7(2019).