气候变化领域集成服务门户(CCPortal): Time variability and uncertainty in the fraction of young water in a small headwater catchment

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DOI	10.5194/hess-23-4333-2019
	Time variability and uncertainty in the fraction of young water in a small headwater catchment
	Paul Stockinger M.; Reemt Bogena H.; Lücke A.; Stumpp C.; Vereecken H.
发表日期	2019
ISSN	1027-5606
起始页码	4333
结束页码	4347
卷号	23 期号:10
英文摘要	The time precipitation needs to travel through a catchment to its outlet is an important descriptor of a catchment's susceptibility to pollutant contamination, nutrient loss, and hydrological functioning. The fast component of total water flow can be estimated by the fraction of young water (Fyw), which is the percentage of streamflow younger than 3 months. Fyw is calculated by comparing the amplitudes of sine waves fitted to seasonal precipitation and streamflow tracer signals. This is usually done for the complete tracer time series available, neglecting annual differences in the amplitudes of longer time series. Considering inter-annual amplitude differences, we employed a moving time window of 1 year in weekly time steps over a 4.5-year δ18O tracer time series to calculate 189 Fyw estimates and their uncertainty. They were then tested against the following null hypotheses: (1) at least 90% of Fyw results do not deviate more than ±0.04 (4 %) from the mean of all Fyw results, indicating long-term invariance. Larger deviations would indicate changes in the relative contribution of different flow paths; (2) for any 4-week window, Fyw does not change more than ±0.04, indicating short-term invariance. Larger deviations would indicate a high sensitivity of Fyw to a 1-week to 4-week shift in the start of a 1-year sampling campaign; (3) the Fyw results of 1-year sampling campaigns started in a given calendar month do not change more than ±0.04, indicating seasonal invariance. In our study, all three null hypotheses were rejected. Thus, the Fyw results were timevariable, showed variability in the chosen sampling time, and had no pronounced seasonality. We furthermore found evidence that the 2015 European heat wave and including two winters into a 1-year sampling campaign increased the uncertainty of Fyw. Based on an increase in Fyw uncertainty when the mean adjusted R2 was below 0.2, we recommend further investigations into the dependence of Fyw and its uncertainty to goodness-of-fit measures. Furthermore, while investigated individual meteorological factors did not sufficiently explain variations of Fyw, the runoff coefficient showed a moderate negative correlation of r = -0.50 with Fyw. The results of this study suggest that care must be taken when comparing Fyw of catchments that were based on different calculation periods and that the influence of extreme events and snow must be considered. © 2019 Institute of Electrical and Electronics Engineers Inc.. All rights reserved.
语种	英语
scopus关键词	Catchments; Runoff; Stream flow; Time series; Goodness-of-fit measure; Headwater catchment; Meteorological factors; Negative correlation; Relative contribution; Runoff coefficients; Sampling campaigns; Seasonal precipitations; Uncertainty analysis; catchment; extreme event; headwater; seasonal variation; streamflow; temporal variation; time series; uncertainty analysis; water flow
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/159585
作者单位	Paul Stockinger, M., Agrosphere Institute (IBG-3), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Straße, Jülich, 52425, Germany, Institute for Soil Physics and Rural Water Management, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, Vienna, 1190, Austria; Reemt Bogena, H., Agrosphere Institute (IBG-3), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Straße, Jülich, 52425, Germany; Lücke, A., Agrosphere Institute (IBG-3), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Straße, Jülich, 52425, Germany; Stumpp, C., Institute for Soil Physics and Rural Water Management, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, Vienna, 1190, Austria; Vereecken, H., Agrosphere Institute (IBG-3), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Straße, Jülich, 52425, Germany
推荐引用方式 GB/T 7714	Paul Stockinger M.,Reemt Bogena H.,Lücke A.,et al. Time variability and uncertainty in the fraction of young water in a small headwater catchment[J],2019,23(10).
APA	Paul Stockinger M.,Reemt Bogena H.,Lücke A.,Stumpp C.,&Vereecken H..(2019).Time variability and uncertainty in the fraction of young water in a small headwater catchment.Hydrology and Earth System Sciences,23(10).
MLA	Paul Stockinger M.,et al."Time variability and uncertainty in the fraction of young water in a small headwater catchment".Hydrology and Earth System Sciences 23.10(2019).