气候变化领域集成服务门户(CCPortal): Continuous; near-real-time observations of water stable isotope ratios during rainfall and throughfall events

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DOI	10.5194/hess-23-3007-2019
	Continuous; near-real-time observations of water stable isotope ratios during rainfall and throughfall events
	Herbstritt B.; Gralher B.; Weiler M.
发表日期	2019
ISSN	1027-5606
起始页码	3007
结束页码	3019
卷号	23 期号:7
英文摘要	The water isotopic composition of throughfall is affected by complex diffusive exchange with ambient water vapour, evaporative enrichment of heavy isotopes, and mixing processes in the tree canopy. All interception processes occur simultaneously in space and time, generating a complex pattern of throughfall depth and water isotopic composition. This pattern ultimately cascades through the entire hydrologic system and is therefore crucial for isotope studies in catchment hydrology, where recharge areas are often forested, while reference meteorological stations are generally in the open. For the quasi real-time observation of the water isotopic composition (d18O and d2H) of both gross precipitation and throughfall, we developed an approach combining a membrane contactor (Membrana) with a laser-based Cavity Ring-Down Spectrometer (CRDS, Picarro), obtaining isotope readings every 2 s. A setup with two CRDS instruments in parallel analysing gross precipitation and throughfall simultaneously was used for the continuous observation of the temporal effect of interception processes on the stable isotopes of water. All devices were kept small to minimize dead volume with time lags of only 4 min for water from the rainfall collectors to the isotope analysers to increase the temporal resolution of isotope observations. Complementarily, meteorological variables were recorded at high temporal resolution at the same location. The achieved evolution from discrete liquid or event-based bulk samples to continuous measurements allows for direct comparison of water stable isotope data with common meteorological measurements. Future improvements of the spatial representativeness will make our approach an even more powerful tool towards detailed insight into the dynamic processes contributing to interception during rainfall events. © 2019 Author(s).
语种	英语
scopus关键词	Catchments; Light measurement; Rain; Continuous measurements; Continuous observation; High temporal resolution; Meteorological measurements; Meteorological station; Meteorological variables; Stable isotopes of water; Water stable isotopes; Isotopes; catchment; instrumentation; interception; isotopic composition; isotopic ratio; observational method; rainfall; real time; spectrometer; stable isotope; throughfall
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/159644
作者单位	Herbstritt, B., Hydrology, Faculty of Environment and Natural Resources, Albert Ludwig University, Freiburg, 79098, Germany; Gralher, B., Hydrology, Faculty of Environment and Natural Resources, Albert Ludwig University, Freiburg, 79098, Germany; Weiler, M., Hydrology, Faculty of Environment and Natural Resources, Albert Ludwig University, Freiburg, 79098, Germany
推荐引用方式 GB/T 7714	Herbstritt B.,Gralher B.,Weiler M.. Continuous; near-real-time observations of water stable isotope ratios during rainfall and throughfall events[J],2019,23(7).
APA	Herbstritt B.,Gralher B.,&Weiler M..(2019).Continuous; near-real-time observations of water stable isotope ratios during rainfall and throughfall events.Hydrology and Earth System Sciences,23(7).
MLA	Herbstritt B.,et al."Continuous; near-real-time observations of water stable isotope ratios during rainfall and throughfall events".Hydrology and Earth System Sciences 23.7(2019).