Increasing frequency and intensity of extreme weather events and natural hazards will impact British Columbia’s critical infrastructure. The province’s transportation network, port facilities, electricity and communications distribution systems are major investments where replacements or upgrades also present opportunities for climate change adaptation. The objective of this project was to provide present and future values of climate parameters in the vicinity of British Columbia’s Coquihalla Highway.
Using station observations and future conditions from Regional Climate Models (RCMs), probability increases were derived: 1%, 5%, 50%, 95%, and 99% quantiles of daily, and where available, 3-hourly values of temperature and precipitation. This information was the basis for deriving many subsequent climate parameters. Additionally, probability estimates for present and future conditions were computed for some of the most important extreme events (e.g., heavy rainfall). This was achieved by mapping local event thresholds to the corresponding thresholds for future conditions with identical probability. Future probabilities were determined directly from the RCM scenarios and assigned to the corresponding future local events.
Estimates of present and future values of climate parameters for the Coquihalla Highway study area were produced. The parameters are probability measures of extreme weather events based on historical records and future projections of temperature and precipitation. For example, future projections using three RCMs indicated that temperature extremes that might occur every two years in the past may occur up to three times every two years by the 2050s.
It must be noted that the approach used in this project involved uncertainties that have not been thoroughly assessed. A more in depth analysis of these uncertainties, especially with regard to extreme events, is being applied for similar projects currently underway in other locations (e.g., Castlegar, Rossland and Vanderhoof).
Columbia Basin Trust and the City of Castlegar, 2011: Adapting to Climate Change: Project Summary Report and Action Plan.
BC Ministry of Transportation and Infrastructure