Modelling spatial and temporal variability of hydrologic impacts of climate change in the Fraser River basin, British Columbia, Canada

Abstract

This paper presents a modelling study on the spatial and temporal variability of climate-induced hydrologic changes in the Fraser River basin, British Columbia, Canada. This large basin presents a unique modelling case due to its physiographic heterogeneity and the potentially large implications of changes to its hydrologic regime. The macro-scale Variable Infiltration Capacity (VIC) hydrologic model was employed to simulate 30-year baseline (1970s) and future (2050s) hydrologic regimes based on climate forcings derived from eight global climate models (GCMs) runs under three emissions scenarios (B1, A1B and A2). Bias Corrected Spatial Disaggregation was used to statistically downscale GCM outputs to the resolution of the VIC model (1/16 ). The modelled future scenarios for the 11 sub-basins and three regions (eastern mountains, central plateau and coastal mountains) of the FRB exhibit spatially varied responses, such as, shifts from snow-dominant to hybrid regime in the eastern and coastal mountains and hybrid to rain-dominant regime in the central plateau region. The analysis of temporal changes illustrated considerable uncertainties in the projections obtained from an ensemble of GCMs and emission scenarios. However, direction of changes obtained from the GCM ensembles and emissions scenarios are consistent amongst one another. The most significant temporal changes could include earlier onsets of snowmelt-driven peak discharge, increased winter and spring runoff and decreased summer runoff. The projected winter runoff increases and summer decreases are more pronounced in the central plateau region. The results also revealed increases in the total annual discharge and decreases in the 30-year mean of the peak annual discharge. Such climate-induced changes could have implications for water resources management in the region. The spatially and temporally varied hydro-climatic projections and their range of projections can be used for local-scale adaptation in this important water resource system for British Columbia.

A modeling framework to assess the impact of climate change on a river runoff

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From earth and ocean: investigating the importance of cross‐ecosystem resource linkages to a mobile estuarine consumer

“…The consideration of potential effects from these industries, and their associated land-use management strategies, should expand beyond direct effects and consider how these activities may alter natural nutrient dynamics that could drive productivity in downstream habitats such as lakes and estuaries. Climatic warming can also alter hydrodynamic regimes through reductions in seasonal flow and shifts in peak flow timing (Shrestha et al 2012). Consequently, the productivity of estuaries may decrease in the future if the influx of terrestrial subsidies depends on river discharge and high-flow events (SalenPicard et al 2002, Darnaude 2005.…”

Planning for climate change impacts on hydropower in the Far North

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