A review of groundwater in high mountain environments

Wiley Interdisciplinary Reviews Water, Journal Year: 2020, Volume and Issue: 7(6)

Published: Oct. 8, 2020

Abstract Mountain water resources are of particular importance for downstream populations but threatened by decreasing storage in snowpack and glaciers. Groundwater contribution to mountain streamflow, once assumed be relatively small, is now understood represent an important source streams. This review presents overview research on groundwater high environments (As classified Meybeck et al. (2001) as very high, mid‐altitude mountains). Coarse geomorphic units, like talus, alluvium, moraines, stores conduits groundwater. Bedrock aquifers contribute catchment streamflow through shallow, weathered bedrock also higher order streams central valley deep fracture flow mountain‐block recharge. Tracer balance studies have shown that contributes substantially many catchments, particularly during low‐flow periods. The percentage attributable varies greatly time between watersheds depending the geology, topography, climate, spatial scale. Recharge spatially variable comes from a combination infiltration rain, snowmelt, glacier melt, well concentrated recharge beneath losing streams, or fractures swallow holes. Recent advances suggest may provide some resilience—at least temporarily—to climate‐driven recession. A paucity field data heterogeneity alpine landscapes remain challenges, new sources, tracers, modeling methods continue expand our understanding flow. article categorized under: Science Water > Hydrological Processes Environmental Change Methods

Language: Английский

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The East River, Colorado, Watershed: A Mountainous Community Testbed for Improving Predictive Understanding of Multiscale Hydrological–Biogeochemical Dynamics

Vadose Zone Journal, Journal Year: 2018, Volume and Issue: 17(1), P. 1 - 25

Published: Jan. 1, 2018

Core Ideas Development of a 300‐km 2 mountainous headwater testbed began in 2016 the East River. The can be used to explore how watershed changes impact downgradient water availability and quality. System‐of‐system, scale‐adaptive approaches potentially improve dynamics simulation. We have new monitor simulate partitioning system responses. River has been developed as “community” testbed. Extreme weather, fires, land use climate change are significantly reshaping interactions within watersheds throughout world. Although hydrological–biogeochemical many services valued by society, uncertainty associated with predicting hydrology‐driven biogeochemical remains high. With an aim reduce this uncertainty, approximately observatory at River, CO, Upper Colorado Basin. site is being for Department Energy supported Watershed Function Project collaborative efforts. Building on insights gained from research “sister” Rifle, site, coordinated studies underway gain predictive understanding retains releases water, nutrients, carbon, metals. In particular, project exploring early snowmelt, drought, other disturbances influence seasonal decadal timescales. A system‐of‐systems perspective simulation approach, involving combined archetypal subsystem “intensive sites” tested inform aggregated predictions exports. Complementing intensive hydrological, geochemical, geophysical, microbiological, geological, vegetation datasets long‐term, distributed measurement stations specialized experimental observational campaigns. Several recent advances provide about sites well behavior. “community testbed” currently hosting scientists more than 30 institutions advance methods understanding.

Language: Английский

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Declining groundwater storage expected to amplify mountain streamflow reductions in a warmer world

Nature Water, Journal Year: 2024, Volume and Issue: 2(5), P. 419 - 433

Published: May 23, 2024

Abstract Groundwater interactions with mountain streams are often simplified in model projections, potentially leading to inaccurate estimates of streamflow response climate change. Here, using a high-resolution, integrated hydrological extending 400 m into the subsurface, we find groundwater an important and stable source historical mountainous watershed Colorado River. In warmer climate, increased forest water use is predicted reduce recharge resulting storage loss. Losses expected be most severe during dry years cannot recover levels even simulated wet periods. depletion substantially reduces annual intermittent conditions when precipitation low. Expanding results across region suggests declines will highest Headwater Gunnison basins. Our research highlights tight coupling vegetation dynamics that excluding explicit warming may underestimate future reductions streamflow.

Language: Английский

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A synopsis of climate change effects on groundwater recharge

Journal of Hydrology, Journal Year: 2017, Volume and Issue: 555, P. 125 - 128

Published: Sept. 29, 2017

Language: Английский

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Simulating coupled surface–subsurface flows with ParFlow v3.5.0: capabilities, applications, and ongoing development of an open-source, massively parallel, integrated hydrologic model

Geoscientific model development, Journal Year: 2020, Volume and Issue: 13(3), P. 1373 - 1397

Published: March 23, 2020

Abstract. Surface flow and subsurface constitute a naturally linked hydrologic continuum that has not traditionally been simulated in an integrated fashion. Recognizing the interactions between these systems encouraged development of models (IHMs) capable treating surface as single resource. IHMs are dynamically evolving with improvements technology, extent their current capabilities often only known to developers general users. This article provides overview core functionality, capability, applications, ongoing one open-source IHM, ParFlow. ParFlow is parallel, integrated, model simulates flows. solves Richards equation for three-dimensional variably saturated groundwater two-dimensional kinematic wave approximation shallow water equations overland flow. The employs conservative centered finite-difference scheme finite-volume method transport, respectively. uses multigrid-preconditioned Krylov Newton–Krylov methods solve linear nonlinear within each time step simulations. code demonstrated very efficient parallel solution capabilities. coupled geochemical reaction, land (e.g., Common Land Model), atmospheric study among subsurface, surface, atmosphere across different spatial scales. focuses on code, simulation engine, primary couplings other codes, taking high-level perspective.

Language: Английский

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Snowmelt controls on concentration‐discharge relationships and the balance of oxidative and acid‐base weathering fluxes in an alpine catchment, East River, Colorado

Water Resources Research, Journal Year: 2017, Volume and Issue: 53(3), P. 2507 - 2523

Published: March 1, 2017

Abstract Although important for riverine solute and nutrient fluxes, the connections between biogeochemical processes subsurface hydrology remain poorly characterized. We investigate these couplings in East River, CO, a high‐elevation shale‐dominated catchment Rocky Mountains, using concentration‐discharge (C‐Q) relationships major cations, anions, organic carbon. Dissolved carbon (DOC) displays positive C‐Q relationship with clockwise hysteresis, indicating mobilization depletion of DOC upper soil horizons emphasizing importance shallow flow paths during snowmelt. Cation anion concentrations demonstrate that carbonate weathering, which dominates is promoted by both sulfuric acid derived from pyrite oxidation shale bedrock carbonic respiration. Sulfuric weathering base conditions when waters infiltrate below inferred front, whereas plays dominant role snowmelt as result paths. Differential solutes suggest infiltrating approach calcite saturation before reaching after reduces alkalinity. This reduction alkalinity results CO 2 outgassing equilibrate to surface conditions, export roughly 33% annually. Future changes dynamics control balance may substantially alter cycling River. Ultimately, we differential can provide unique insights into complex operate at scales.

Language: Английский

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The imprint of climate and geology on the residence times of groundwater

Geophysical Research Letters, Journal Year: 2015, Volume and Issue: 43(2), P. 701 - 708

Published: Dec. 17, 2015

Abstract Surface and subsurface flow dynamics govern residence time or water age until discharge, which is a key metric of storage availability for human use ecosystem function. Although observations in small catchments have shown fractal distribution ages, times are difficult to directly quantify measure large basins. Here we simulation major watersheds across North America compute distributions times. This results peak ages from 1.5 10.5 years, agreement with isotopic bomb‐derived radioisotopes, wide range times—from 0.1 10,000 years. suggests that controlled by the mean hydraulic conductivity, function prevailing geology. The shape dependent on aridity, turn determines table depth frequency shorter paths. These model underscore need additional studies characterize larger systems.

Language: Английский

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The relationship between contrasting ages of groundwater and streamflow

Geophysical Research Letters, Journal Year: 2017, Volume and Issue: 44(17), P. 8925 - 8935

Published: Aug. 29, 2017

Abstract Tracer data demonstrate that waters in aquifers are often much older than the stream drain them. This contrast water ages has lacked a general quantitative explanation. Here we show under stationary conditions, age distribution of stored catchment can be directly estimated from its outflows, and vice versa. turn implies storage selection function, expressing catchment's preference for release or retention different ages, outflow conditions. Using gamma distributions streamflow mean range half as old (for plug flow conditions) to almost infinitely strongly preferential flow). Many have long upper tails, consistent with implying substantially ages. Mean reported literature imply most originates thin veneer total groundwater storage. young is exchanged only slowly surface consequently relatively old.

Language: Английский

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Sensitivity of Catchment Transit Times to Rainfall Variability Under Present and Future Climates

Water Resources Research, Journal Year: 2017, Volume and Issue: 53(12), P. 10231 - 10256

Published: Oct. 24, 2017

Abstract Hydrologists have a relatively good understanding of how rainfall variability shapes the catchment hydrograph, reflection celerity hydraulic head propagation. Much less is known about influence on transit times, water velocities that control solute transport. This work uses catchment‐scale lumped parameter models to decompose relationship between and an important metric time‐varying fraction young (<90 days old) in streams (FYW). A coupled rainfall‐runoff model rank StorAge Selection (rSAS) time were calibrated extensive hydrometric environmental tracer data from neighboring headwater catchments Plynlimon, Wales 1999 2008. At both sites, mean annual FYW increased more than 13 percentage points driest wettest year. Yearly explained most between‐year variation, but certain signatures pattern also associated with higher including: clustered storms, negatively skewed covariance daily discharge. We show these are symptomatic “inverse storage effect” may be common among watersheds. Looking future, changes due projected climate change caused up 19 point increase simulated winter similarly large decreases summer FYW. Thus, could seasonally alter ages at concomitant impacts quality.

Language: Английский

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Cosmogenic Isotopes Unravel the Hydrochronology and Water Storage Dynamics of the Southern Sierra Critical Zone

Water Resources Research, Journal Year: 2019, Volume and Issue: 55(2), P. 1429 - 1450

Published: Jan. 30, 2019

Abstract One of the principal questions in hydrology is how and when water leaves critical zone storage as either stream flow or evapotranspiration. We investigated subsurface selection Southern Sierra Critical Zone Observatory (California, USA) within age‐ranked framework, constrained by a novel combination cosmogenic radioactive stable isotopes: tritium, sodium‐22, sulfur‐35, oxygen‐18. found significant positive correlation between tritium rate sulfur‐35 rate, indicating that age distribution varies with rate. Storage functions vary are better able to reproduce concentrations than constant time. For Zone, there strong preference discharge oldest during dry conditions but only weak for younger wet conditions. The evapotranspiration water, oxygen‐18 essential parameterize needs be confirmed isotopic other investigations This first study illustrate isotopes reveals hydrochronology dynamics catchments, constrains architecture zone, provides insight into landscape evolution.

Language: Английский

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