Abstract Manager

Climate change in Canada has introduced significant challenges to the performance and durability of flexible pavements due to increases in temperature and precipitation. To address these challenges, it is important to understand the influence of climate change on the key environmental parameters affecting pavement design. Climate Adaptation and Asphalt Selection Tool (CAAST) would be employed to capture the variations of climatic loadings on those environmental parameters for four pavement design cycles of 25 years from 2000 to 2100. The analysis incorporates historical (2000–2025) and projected short-term (2025–2050), intermediate-term (2050–2075), and long-term (2075–2100) hourly climate data from Environment and Climate Change Canada (ECCC), downscaled using the Canadian Regional Climate Model (CanRCM4) for different cities across Canada. Considering the highest emission scenarios of Representative Concentration Pathways (RCP 8.5), this downscaled climatic data would be then fed into the CAAST to calculate critical environmental parameters such as Mean Annual Air Temperature (MAAT), Mean Annual Lowest Air Temperature (MALAT), Mean Annual Highest Air Temperature (MAHAT), Mean Annual Degree Days (MADD), Mean Annual Precipitation (MAP), freezing index, and average annual freeze-thaw cycles. It is predicted that MAAT will be increasing consistently across all cities, especially northern cities, which would experience a sharp increase threatening permafrost stability. MALAT will also increase, reducing risks of low-temperature cracking, particularly in southern regions. MAHAT is expected to double in some areas, intensifying rutting. MADD will rise significantly, indicating extended warm seasons, while MAP will increase, weakening pavement subgrades. The freezing index will decline, but freeze-thaw cycles will intensify in transitional regions, exacerbating pavement deterioration. These findings would underscore the importance of incorporating climate projections into road design for improved resilience.

Keywords: Climate Change, Environment and Climate Change Canada (ECCC), Representative Concentration Pathways (RCPs), Pavement Performance, Climate Adaptation and Asphalt Selection Tool (CAAST)