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

Area of Science:

• Hydrology
• Climate Science
• Environmental Modeling

Background:

• Climate change significantly impacts global water resources, particularly in regions with substantial snowfall and melting.
• Understanding these impacts is crucial for water resource management and infrastructure planning.

Purpose of the Study:

• To assess the potential impacts of climate change on surface and subsurface water flow in the Saint-Charles River catchment, Quebec.
• To simulate hydrological system responses to projected climate scenarios using a modified integrated hydrological model.

Main Methods:

• Modification of the HydroGeoSphere (HGS) model to incorporate snow accumulation and melting processes.
• Calibration of the HGS model using current climate data for streamflow and hydraulic head.
• Simulation of future hydrological conditions (2070-2100) using three distinct climate change scenarios.

Main Results:

• Projected winter stream discharge increases of 80-150% due to increased liquid precipitation and snowmelt.
• Predicted summer stream discharge decreases of 10-20% attributed to rising evapotranspiration.
• Annual mean stream discharge expected to remain relatively stable, with significant seasonal shifts in hydraulic head (up to 15m winter increase, 3m summer decrease).

Conclusions:

• Winter hydrological processes are critical drivers of seasonal flow dynamics under climate change.
• The Saint-Charles River catchment is vulnerable to significant seasonal flow alterations, necessitating adaptive management strategies.
• Integrated surface-subsurface flow models are valuable tools for predicting climate change impacts on water resources.