气候变化领域集成服务门户(CCPortal): Multi-scale temporal variability in meltwater contributions in a tropical glacierized watershed

CCPortal

DOI	10.5194/hess-23-405-2019
	Multi-scale temporal variability in meltwater contributions in a tropical glacierized watershed
	Saberi L.; McLaughlin R.T.; Crystal Ng G.-H.; La Frenierre J.; Wickert A.D.; Baraer M.; Zhi W.; Li L.; Mark B.G.
发表日期	2019
ISSN	1027-5606
起始页码	405
结束页码	425
卷号	23 期号:1
英文摘要	Climate models predict amplified warming at high elevations in low latitudes, making tropical glacierized regions some of the most vulnerable hydrological systems in the world. Observations reveal decreasing streamflow due to retreating glaciers in the Andes, which hold 99% of all tropical glaciers. However, the timescales over which meltwater contributes to streamflow and the pathways it takes-surface and subsurface-remain uncertain, hindering our ability to predict how shrinking glaciers will impact water resources. Two major contributors to this uncertainty are the sparsity of hydrologic measurements in tropical glacierized watersheds and the complication of hydrograph separation where there is year-round glacier melt. We address these challenges using a multi-method approach that employs repeat hydrochemical mixing model analysis, hydroclimatic time series analysis, and integrated watershed modeling. Each of these approaches interrogates distinct timescale relationships among meltwater, groundwater, and stream discharge. Our results challenge the commonly held conceptual model that glaciers buffer discharge variability. Instead, in a subhumid watershed on Volcán Chimborazo, Ecuador, glacier melt drives nearly all the variability in discharge (Pearson correlation coefficient of 0.89 in simulations), with glaciers contributing a broad range of 20%-60% or wider of discharge, mostly (86%) through surface runoff on hourly timescales, but also through infiltration that increases annual groundwater contributions by nearly 20%. We further found that rainfall may enhance glacier melt contributions to discharge at timescales that complement glacier melt production, possibly explaining why minimum discharge occurred at the study site during warm but dry El Niño conditions, which typically heighten melt in the Andes. Our findings caution against extrapolations from isolated measurements: stream discharge and glacier melt contributions in tropical glacierized systems can change substantially at hourly to interannual timescales, due to climatic variability and surface to subsurface flow processes. © 2019 Author(s).
语种	英语
scopus关键词	Climate models; Correlation methods; Groundwater; Stream flow; Time series analysis; Uncertainty analysis; Water resources; Watersheds; Climatic variability; Hydrograph separation; Hydrologic measurements; Hydrological system; Multi-method approach; Pearson correlation coefficients; Temporal variability; Watershed modeling; Tropics; climate variation; El Nino; glacier; groundwater; hydrological modeling; meltwater; rainfall; runoff; streamflow; subsurface flow; temporal variation; watershed; Andes; Chimborazo; Ecuador; Ecuador
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/159784
作者单位	Saberi, L., Department of Earth Sciences, University of Minnesota, Twin Cities, Minneapolis, MN 55455, United States; McLaughlin, R.T., Department of Earth Sciences, University of Minnesota, Twin Cities, Minneapolis, MN 55455, United States; Crystal Ng, G.-H., Department of Earth Sciences, University of Minnesota, Twin Cities, Minneapolis, MN 55455, United States, Saint Anthony Falls Laboratory, University of Minnesota, Twin Cities, Minneapolis, MN 55414, United States; La Frenierre, J., Department of Geography, Gustavus Adolphus College, St. Peter, MN 56082, United States; Wickert, A.D., Department of Earth Sciences, University of Minnesota, Twin Cities, Minneapolis, MN 55455, United States, Saint Anthony Falls Laboratory, University of Minnesota, Twin Cities, Minneapolis, MN 55414, United States; Baraer, M., Construction Engineering École de Technologie Supérieure, Université du Québec, Montreal, H3C 1K3, Canada; Zhi, W., Department of Civil and Environmental Engineering, Pennsylvania State Unive...
推荐引用方式 GB/T 7714	Saberi L.,McLaughlin R.T.,Crystal Ng G.-H.,et al. Multi-scale temporal variability in meltwater contributions in a tropical glacierized watershed[J],2019,23(1).
APA	Saberi L..,McLaughlin R.T..,Crystal Ng G.-H..,La Frenierre J..,Wickert A.D..,...&Mark B.G..(2019).Multi-scale temporal variability in meltwater contributions in a tropical glacierized watershed.Hydrology and Earth System Sciences,23(1).
MLA	Saberi L.,et al."Multi-scale temporal variability in meltwater contributions in a tropical glacierized watershed".Hydrology and Earth System Sciences 23.1(2019).