Climate Indicators of Landslide Risks on Alaska National Park Road Corridors

Landslides along road corridors in Alaska national parks pose threats to public safety, visitor access, subsistence activities, and result costly remediation of damaged infrastructure. Landslide risk these areas, which contain near-surface permafrost, is associated with mean annual air temperatures (MAATs) above freezing heavy precipitation events. Historical (1981–2020) values MAAT summer (JJA PCPT) from the fifth generation European Centre for Medium-Range Weather Forecasts (Reading, UK) atmospheric reanalysis (ERA5) were compared mid-century (2021–2060) late-century (2061–2100) downscaled climate model projections across Gates Arctic National Park Preserve (GAAR), Denali (DENA), Wrangell-St. Elias (WRST). ERA5 showed that all locations historically had below freezing, but three warming significantly (0.3–0.6 °C per decade). Observed trends 18 stations 11 being significant at 95% confidence level using Mann–Kendall non-parametric test. Road corridor are given the: (1) proposed Ambler through GAAR, (2) DENA, (3) McCarthy WRST. Elevated was projected period park period; elevated JJA PCPT periods corridors.