Integrated Hydrological Modeling of Climate Change Impacts in a Snow‐Influenced Catchment

Abstract

The potential impact of climate change on water resources has been intensively studied for different regions and climates across the world. In regions where winter processes such as snowfall and melting play a significant role, anticipated changes in temperature might significantly affect hydrological systems. To address this impact, modifications have been made to the fully integrated surface‐subsurface flow model HydroGeoSphere (HGS) to allow the simulation of snow accumulation and melting. The modified HGS model was used to assess the potential impact of climate change on surface and subsurface flow in the Saint‐Charles River catchment, Quebec (Canada) for the period 2070 to 2100. The model was first developed and calibrated to reproduce observed streamflow and hydraulic heads for current climate conditions. The calibrated model was then used with three different climate scenarios to simulate surface flow and groundwater dynamics for the 2070 to 2100 period. Winter stream discharges are predicted to increase by about 80, 120, and 150% for the three scenarios due to warmer winters, leading to more liquid precipitation and more snowmelt. Conversely, the summer stream discharges are predicted to fall by about 10, 15, and 20% due to an increase in evapotranspiration. However, the annual mean stream discharge should remain stable (±0.1 m3/s). The predicted increase in hydraulic heads in winter may reach 15 m and the maximum decrease in summer may reach 3 m. Simulations show that winter processes play a key role in the seasonal modifications anticipated for surface and subsurface flow dynamics.

Beyond Classical Observations in Hydrogeology: The Advantages of Including Exchange Flux, Temperature, Tracer Concentration, Residence Time, and Soil Moisture Observations in Groundwater Model Calibration

“…But with the capabilities of the current generation of flow models, one is no longer restricted to the simulation of such simple GW systems anymore or forced to oversimplify more complex GW systems—the current trend is toward the simulation of complex systems based on integrated surface water (SW)‐GW flow models (IFMs; Barthel & Banzhaf, ; Paniconi & Putti, ). Compared to numerical models that exclusively simulate GW flow, IFMs enable the simulation of GW and SW flow in a physically‐based and fully‐coupled way and allow the inclusion of many hydrologically relevant processes such as unsaturated flow through complex heterogeneous structures (e.g., Irvine et al, ; Schilling, Irvine, et al, ; Tang et al, , ), heat and mass transport (e.g., Carniato et al, ; Karan et al, ; Kurtz et al, ; Schilling et al, ), snow accumulation, melt and pore water freeze‐thaw (e.g., Cochand et al, ; Evans & Ge, ; Painter et al, ; Schilling et al, ; Shojae Ghias et al, ), and SW‐GW‐vegetation interactions (e.g., Banks et al, ; Maxwell & Condon, ; Schomburg et al, ). Compared to numerical flow models that exclusively simulate GW flow, IFMs require more parameters and boundary conditions to be defined and calibrated (the minimally required parameters and boundary conditions of different types of GW and SW simulations are listed in Table ).…”

Integrated Surface and Subsurface Hydrological Modeling with Snowmelt and Pore Water Freeze–Thaw

“…Most relevant data required for winter hydrological simulations with HGS are readily available, and there is no extra effort involved in setting up an integrated SW‐GW model for winter‐influenced catchments. With the efficient implementation of winter hydrological processes into HGS, intra‐ as well as inter‐annual simulations of small catchments under the influence of winter can be undertaken on normal desktop machines, and more complex simulations, for example of large catchments under climate change scenarios, can be simulated on computational cloud infrastructure (Kurtz et al ; Cochand et al ). The representation of winter hydrological processes in HGS relies on some simplifying assumptions, such as uniform thermal properties and negligible heat transfer by convection in the subsurface.…”

Parameterisation of an integrated groundwater-surface water model for hydrological analysis of boreal aapa mire wetlands

“…The steady-state results, thus, may not be relevant for depicting the spatial dynamics of the actual system and does not provide any information on the temporal variability of GW-SW interactions, which can fluctuate significantly during various seasons of the year (Ala-aho et al, 2015a). Especially, winter and spring discharges might be strongly biased as winter processes, such as snow accumulation, snowmelt and soil freezing and thawing, were not included in this model despite winter conditions can prevail over 6 months of the year in the Kälväsvaara area and are of great importance in northern locations (Cochand et al, 2019;Schilling et al, 2019). This means that, winter and spring discharges may be sensitive to parametrization of winter processes, but these effects were beyond the scope of this study.…”