Cochand Fabien, Therrien René, Lemieux Jean-Michel
Department of Geology and Geological Engineering, Université Laval, Québec, Canada G1V 0A6.
Centre of Hydrogeology and Geothermics, Université de Neuchâtel, Neuchâtel, Switzerland.
Ground Water. 2019 Jan;57(1):3-20. doi: 10.1111/gwat.12848. Epub 2018 Dec 19.
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 m /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.
气候变化对水资源的潜在影响已在全球不同地区和气候条件下得到深入研究。在降雪和融雪等冬季过程起重要作用的地区，预期的温度变化可能会对水文系统产生重大影响。为应对这种影响，对完全集成的地表水 - 地下水流动模型HydroGeoSphere（HGS）进行了修改，以允许模拟积雪和融雪过程。修改后的HGS模型用于评估2070年至2100年期间气候变化对加拿大魁北克圣查尔斯河流域地表水和地下水流动的潜在影响。该模型首先被开发和校准，以再现当前气候条件下观测到的河流流量和水头。然后，使用校准后的模型结合三种不同的气候情景，模拟2070年至2100年期间的地表水流和地下水动态。由于冬季变暖，预计三种情景下冬季河流流量将分别增加约80%、120%和150%，导致液态降水增加和融雪增多。相反，由于蒸发散增加，预计夏季河流流量将分别下降约10%、15%和20%。然而，年平均河流流量应保持稳定（±0.1立方米/秒）。预计冬季水头的增加可能达到15米，夏季的最大降幅可能达到3米。模拟结果表明，冬季过程在预期的地表水和地下水流动动态的季节性变化中起着关键作用。
