Estimating glacier and snowmelt contributions to stream flow in a Central Andes catchment in Chile using natural tracers

Rodríguez, Maximiliano; Ohlanders, N.; McPhee, James

doi:10.5194/hessd-11-8949-2014

Cited by 6 publications

(6 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Cable et al ., ; Penna et al ., ; Taylor et al ., ) have been able to more directly characterize end‐members by sampling glacier ice, snowmelt through snow lysimeters or groundwater from wells. Limitations in our experimental setup prevented us from achieving this (Rodriguez et al ., ). However, of the three identified sources used in hydrograph separation, two – EAST and SOUTH – were derived after analysing several water samples collected at regular intervals during the water year.…”

Section: Resultsmentioning

confidence: 97%

Estimating runoff from a glacierized catchment using natural tracers in the semi‐arid Andes cordillera

Rodríguez

Ohlanders

Pellicciotti

et al. 2016

Hydrological Processes

View full text Add to dashboard Cite

This paper presents a methodology for hydrograph separation in mountain watersheds, which aims at identifying flow sources among ungauged headwater sub-catchments through a combination of observed streamflow and data on natural tracers including isotope and dissolved solids. Daily summer and bi-daily spring season water samples obtained at the outlet of the Juncal River Basin in the Andes of Central Chile were analysed for all major ions as well as stable water isotopes, O-18 and D. Additionally, various samples from rain, snow, surface streams and exfiltrating subsurface water (springs) were sampled throughout the catchment. A principal component analysis was performed in order to address cross-correlation in the tracer dataset, reduce the dimensionality of the problem and uncover patterns of variability. Potential sources were identified in a two-component U-space that explains 94% of the observed tracer variability at the catchment outlet. Hydrograph separation was performed through an Informative-Bayesian model. Our results indicate that the Juncal Norte Glacier headwater sub-catchment contributed at least 50% of summer flows at the Juncal River Basin outlet during the 2011-2012 water year (a hydrologically dry period in the Region), even though it accounts for only 27% of the basin area. Our study confirms the value of combining solute and isotope information for estimating source contributions in complex hydrologic systems, and provides insights regarding experimental design in high-elevation semi-arid catchments. The findings of this study can be useful for evaluating modelling studies of the hydrological consequences of the rapid decrease in glacier cover observed in this region, by providing insights into the origin of river water in basins with little hydrometeorological information. Copyright (c) 2016 John Wiley & Sons, Ltd

show abstract

Section: Resultsmentioning

confidence: 97%

Estimating runoff from a glacierized catchment using natural tracers in the semi‐arid Andes cordillera

Rodríguez

Ohlanders

Pellicciotti

et al. 2016

Hydrological Processes

View full text Add to dashboard Cite

show abstract

“…In glacier-fed river systems, the principal water sources to bulk run-off derive from ice melt, snowmelt, rainfall and groundwater components. Depending on the objectives of the study and on the environmental setting, hydrograph separation of glacial rivers has been based on assumed endmember isotope mixing between two or three prevailing components (Behrens et al, 1971(Behrens et al, , 1978Fairchild et al, 1999;Mark and Seltzer, 2003;Theakstone, 2003;Yde and Knudsen, 2004;Mark and McKenzie, 2007;Yde et al, 2008;Bhatia et al, 2011;Kong and Pang, 2012;Ohlanders et al, 2013;Blaen et al, 2014;Dahlke et al, 2014;Hindshaw et al, 2014;Meng et al, 2014;Penna et al, 2014;Rodriguez et al, 2014;Zhou et al, 2014). As glacierised catchments vary in size, altitudinal range, hypsometry, degree of glaciation, and thermal and morphological glacier types, isotope hydrograph separation often requires that the primary local controls on run-off generation are identified in order to analyse the variability in isotope time series.…”

Section: Introductionmentioning

confidence: 99%

Stable oxygen isotope variability in two contrasting glacier river catchments in Greenland

Yde

Knudsen

Steffensen

et al. 2016

Hydrol. Earth Syst. Sci.

View full text Add to dashboard Cite

Abstract. Analysis of stable oxygen isotope (δ18O) characteristics is a useful tool to investigate water provenance in glacier river systems. In order to attain knowledge on the diversity of δ18O variations in Greenlandic rivers, we examined two contrasting glacierised catchments disconnected from the Greenland Ice Sheet (GrIS). At the Mittivakkat Gletscher river, a small river draining a local temperate glacier in southeast Greenland, diurnal oscillations in δ18O occurred with a 3 h time lag to the diurnal oscillations in run-off. The mean annual δ18O was −14.68 ± 0.18 ‰ during the peak flow period. A hydrograph separation analysis revealed that the ice melt component constituted 82 ± 5 % of the total run-off and dominated the observed variations during peak flow in August 2004. The snowmelt component peaked between 10:00 and 13:00 local time, reflecting the long travel time and an inefficient distributed subglacial drainage network in the upper part of the glacier. At the Kuannersuit Glacier river on the island Qeqertarsuaq in west Greenland, the δ18O characteristics were examined after the major 1995–1998 glacier surge event. The mean annual δ18O was −19.47 ± 0.55 ‰. Despite large spatial variations in the δ18O values of glacier ice on the newly formed glacier tongue, there were no diurnal oscillations in the bulk meltwater emanating from the glacier in the post-surge years. This is likely a consequence of a tortuous subglacial drainage system consisting of linked cavities, which formed during the surge event. Overall, a comparison of the δ18O compositions from glacial river water in Greenland shows distinct differences between water draining local glaciers and ice caps (between −23.0 and −13.7 ‰) and the GrIS (between −29.9 and −23.2 ‰). This study demonstrates that water isotope analyses can be used to obtain important information on water sources and the subglacial drainage system structure that is highly desired for understanding glacier hydrology.

show abstract

“…This finding is common in hydrograph separation studies, where pre-existing water tends to dominate streamflow peaks during storm events (Buttle, 1994), and it is especially common in hydrograph separations performed in permeable catchments (Muñoz-Villers and McDonnell, 2012). An exception to this, however, are snowmelt-dominated and glaciated catchments, which tend to exhibit larger precipitation volumes contributing to streamflow in the form of snow or glacier melt (Cable et al, 2011;Rodriguez et al, 2014;Dahlke et al, 2014). Thus, it appears from our results that the permeable geology of the Diguillín promotes snowmelt recharge rather than direct input of snowmelt to streamflow, despite a major amount of precipitation falling as snow in the uplands.…”

Section: Precipitationmentioning

confidence: 55%

Bayesian hydrograph separation in a minimally gauged alpine volcanic watershed in central Chile

Markovich

Dahlke

Arumí

et al. 2019

Journal of Hydrology

View full text Add to dashboard Cite

This study examines the question of how much information one can extract from a tracer-based hydrograph separation in a remote and minimally gaged alpine catchment in Chile. We combine PCA-based endmember mixing analysis to identify the sources of flow contribution to the Diguillín River with a hierarchical Bayesian mixing model to integrate spatial and temporal variability in endmember concentration and quantify the source contributions to streamflow over time. The PCA-analysis shows that precipitation isotopes do not vary by elevation (e.g. snow and rainfall had identical signatures) but vary significantly by season, and that a third endmember is necessary to bound streamflow variability at the basin outlet, which was not captured by our field sampling. One of the main advantages of Bayesian methods is the quasi-machine learning capabilities, where we treated the third endmember as a parameter from which the mixing model could both estimate proportional contributions as well as posterior estimates for the tracer concentrations. The two tracer, three endmember hydrograph separation revealed groundwater to be the largest and precipitation (rain and snow) to be the smallest contributor, on average, to streamflow with the third unknown endmember contributing around 40% of streamflow during the Winter wet season. We hypothesize that interflow is occurring as the third endmember in the Alto Diguillín subwatershed, based on inferred tracer values and the presence of alluvium atop impermeable bedrock along certain reaches. More work is necessary to observe and sample these flowpaths, which was not possible during this study. The results of this work have implications for water resource management, since groundwater sustains the majority of streamflow in the Diguillín, and climate change will impact the timing and quantity of baseflow and interflow. Overall, we demonstrate the utility of combining PCA with Bayesian statistical modeling and inference to extract maximum information from a limited field dataset in a remote alpine catchment. The findings of this work can guide future water management in the Diguillín, but also provide clear questions for future research.

show abstract

Estimating glacier and snowmelt contributions to stream flow in a Central Andes catchment in Chile using natural tracers

Cited by 6 publications

References 41 publications

Estimating runoff from a glacierized catchment using natural tracers in the semi‐arid Andes cordillera

Estimating runoff from a glacierized catchment using natural tracers in the semi‐arid Andes cordillera

Stable oxygen isotope variability in two contrasting glacier river catchments in Greenland

Bayesian hydrograph separation in a minimally gauged alpine volcanic watershed in central Chile

Contact Info

Product

Resources

About