Assessment of the Cumulative Effects of Climate Change and Land Use to the Trans Mountain Pipeline and Wildlife Habitat in the North Thompson Watershed

The analysis applied the ALCES® Online landscape simulation model and the Raven hydrological modeling framework to explore the long-term (50-year) consequences of climate change, land use, and natural disturbance to landscape composition, streamflow, and wildlife habitat in the North Thompson watershed. The business as usual landscape simulation incorporated expansion of the Trans Mountain pipeline as well as other land uses (forestry, settlements, mining) occurring in the region. Fire was also included in the landscape simulations, under three scenarios: no effect of climate change on fire rate, a moderate increase in fire rate under a Representative Concentration Pathway (RCP) 2.6 Climate Scenario, and a high increase in fire rate under a RCP 8.5 Climate Scenario. Outcomes from the landscape simulation informed hydrological modelling, and were applied to map the cumulative effect of simulated land use and fire to indicators including landscape composition, old forest, moose habitat, and grizzly bear mortality risk. To aid interpretation of indicator performance, simulations of the natural fire regime in the absence of land use were also completed and applied to estimate natural conditions and associated indicator levels.