气候变化领域集成服务门户(CCPortal): Technical note: An improved discharge sensitivity metric for young water fractions

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DOI	10.5194/hess-24-1101-2020
	Technical note: An improved discharge sensitivity metric for young water fractions
	Gallart F.; Von Freyberg J.; Valiente M.; Kirchner J.W.; Llorens P.; Latron J.
发表日期	2020
ISSN	1027-5606
起始页码	1101
结束页码	1107
卷号	24 期号:3
英文摘要	Recent virtual and experimental investigations have shown that the young water fraction Fyw (i.e. the proportion of catchment outflow younger than circa 2-3 months) increases with discharge in most catchments. The discharge sensitivity of Fyw has been defined as the rate of increase in Fyw with increasing discharge (Q) and has been estimated by the linear regression slope between Fyw and Q, hereafter called DS(Q). The combined use of both metrics, Fyw and DS(Q), provides a promising method for catchment intercomparison studies that seek to understand streamflow generation processes. Here we explore the discharge sensitivity of Fyw in the intensively sampled small Mediterranean research catchment Can Vila. Intensive sampling of high flows at Can Vila allows young water fractions to be estimated for the far upper tail of the flow frequency distribution. These young water fractions converge toward 1 at the highest flows, illustrating a conceptual limitation in the linear regression method for estimating DS(Q) as a metric of discharge sensitivity: Fyw cannot grow with discharge indefinitely, since the fraction of young water in discharge can never be larger than 1. Here we propose to quantify discharge sensitivity by the parameter of an exponential-type equation that expresses how Fyw varies with discharge. The exponential parameter (Sd) approximates DS(Q) at moderate discharges where Fyw is well below 1; however, the exponential equation and its discharge sensitivity metric better capture the non-linear relationship between Fyw and Q and are robust with respect to changes in the range of sampled discharges, allowing comparisons between catchments with strongly contrasting flow regimes. © Author(s) 2020.
语种	英语
scopus关键词	Regression analysis; Runoff; Experimental investigations; Exponential equations; Exponential type; Intensive sampling; Intercomparisons; Linear regression methods; Non-linear relationships; Streamflow generations; Catchments; catchment; discharge; experimental study; Mediterranean environment; outflow; regression analysis; sampling; streamflow
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/159479
作者单位	Gallart, F., Surface Hydrology and Erosion Group, Department of Geosciences, IDAEA, CSIC, Barcelona, Spain; Von Freyberg, J., Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland; Valiente, M., Geodynamics Department, University of the Basque Country, Leioa, Spain; Kirchner, J.W., Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland; Llorens, P., Surface Hydrology and Erosion Group, Department of Geosciences, IDAEA, CSIC, Barcelona, Spain; Latron, J., Surface Hydrology and Erosion Group, Department of Geosciences, IDAEA, CSIC, Barcelona, Spain
推荐引用方式 GB/T 7714	Gallart F.,Von Freyberg J.,Valiente M.,et al. Technical note: An improved discharge sensitivity metric for young water fractions[J],2020,24(3).
APA	Gallart F.,Von Freyberg J.,Valiente M.,Kirchner J.W.,Llorens P.,&Latron J..(2020).Technical note: An improved discharge sensitivity metric for young water fractions.Hydrology and Earth System Sciences,24(3).
MLA	Gallart F.,et al."Technical note: An improved discharge sensitivity metric for young water fractions".Hydrology and Earth System Sciences 24.3(2020).