气候变化领域集成服务门户(CCPortal): Pacific climate reflected in Waipuna Cave drip water hydrochemistry

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DOI	10.5194/hess-24-3361-2020
	Pacific climate reflected in Waipuna Cave drip water hydrochemistry
	Nava-Fernandez C.; Hartland A.; Gázquez F.; Kwiecien O.; Marwan N.; Fox B.; Hellstrom J.; Pearson A.; Ward B.; French A.; Hodell D.A.; Immenhauser A.; Breitenbach S.F.M.
发表日期	2020
ISSN	1027-5606
起始页码	3361
结束页码	3380
卷号	24 期号:6
英文摘要	Cave microclimate and geochemical monitoring is vitally important for correct interpretations of proxy time series from speleothems with regard to past climatic and environmental dynamics. We present results of a comprehensive cave-monitoring programme in Waipuna Cave in the North Island of New Zealand, a region that is strongly influenced by the Southern Westerlies and the El Niño-Southern Oscillation (ENSO). This study aims to characterise the response of the Waipuna Cave hydrological system to atmospheric circulation dynamics in the southwestern Pacific region in order to assure the quality of ongoing palaeo-environmental reconstructions from this cave. Drip water from 10 drip sites was collected at roughly monthly intervals for a period of ca. 3 years for isotopic (d18O, dD, d-excess parameter, d17O, and 17Oexcess) and elemental (Mg=Ca and Sr=Ca) analysis. The monitoring included spot measurements of drip rates and cave air CO2 concentration. Cave air temperature and drip rates were also continuously recorded by automatic loggers. These datasets were compared to surface air temperature, rainfall, and potential evaporation from nearby meteorological stations to test the degree of signal transfer and expression of surface environmental conditions in Waipuna Cave hydrochemistry. Based on the drip response dynamics to rainfall and other characteristics, we identified three types of discharge associated with hydrological routing in Waipuna Cave: (i) type 1-diffuse flow, (ii) type 2-fracture flow, and (iii) type 3-combined flow. Drip water isotopes do not reflect seasonal variability but show higher values during severe drought. Drip water d18O values are characterised by small variability and reflect the mean isotopic signature of precipitation, testifying to rapid and thorough homogenisation in the epikarst. Mg=Ca and Sr=Ca ratios in drip waters are predominantly controlled by prior calcite precipitation (PCP). Prior calcite precipitation is strongest during austral summer (December-February), reflecting drier conditions and a lack of effec tive infiltration, and is weakest during the wet austral winter (July-September). The Sr=Ca ratio is particularly sensitive to ENSO conditions due to the interplay of congruent or incongruent host rock dissolution, which manifests itself in lower Sr=Ca in above-average warmer and wetter (La Niña-like) conditions. Our microclimatic observations at Waipuna Cave provide a valuable baseline for the rigorous interpretation of speleothem proxy records aiming at reconstructing the past expression of Pacific climate modes. © 2020 Author(s).
语种	英语
scopus关键词	Atmospheric pressure; Atmospheric temperature; Calcite; Climatology; Dynamics; Hydrochemistry; Isotopes; Rain; Atmospheric circulation; Environmental conditions; Environmental dynamics; Environmental reconstruction; Geochemical monitoring; Meteorological station; Prior calcite precipitations; Surface air temperatures; Caves; atmospheric circulation; cave; El Nino-Southern Oscillation; hydrochemistry; paleoclimate; paleoenvironment; reconstruction; speleothem; westerly; Pacific Ocean; Pacific Ocean (Southwest)
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/159362
作者单位	Nava-Fernandez, C., Department for Sediment-and Isotope Geology, Institute for Geology, Mineralogy and Geophysics, Ruhr-Universität Bochum, Universitätsstr. 150, Bochum, 44801, Germany; Hartland, A., Environmental Research Institute, School of Science, Faculty of Science and Engineering, University of Waikato, Hamilton, Waikato, New Zealand; Gázquez, F., Department of Biology and Geology, Universidad de Almería, Almería, 04120, Spain; Kwiecien, O., Department for Sediment-and Isotope Geology, Institute for Geology, Mineralogy and Geophysics, Ruhr-Universität Bochum, Universitätsstr. 150, Bochum, 44801, Germany, Department of Geography and Environmental Sciences, Northumbria University, Newcastle upon Tyne, NE1-8ST, United Kingdom; Marwan, N., Potsdam Institute for Climate Impact Research (PIK), Member of the Leibniz Association, Potsdam, Germany, Institute of Geosciences, University of Potsdam, Potsdam, Germany; Fox, B., Environmental Research Institute, School of Science, Faculty of Science and Engineeri...
推荐引用方式 GB/T 7714	Nava-Fernandez C.,Hartland A.,Gázquez F.,et al. Pacific climate reflected in Waipuna Cave drip water hydrochemistry[J],2020,24(6).
APA	Nava-Fernandez C..,Hartland A..,Gázquez F..,Kwiecien O..,Marwan N..,...&Breitenbach S.F.M..(2020).Pacific climate reflected in Waipuna Cave drip water hydrochemistry.Hydrology and Earth System Sciences,24(6).
MLA	Nava-Fernandez C.,et al."Pacific climate reflected in Waipuna Cave drip water hydrochemistry".Hydrology and Earth System Sciences 24.6(2020).