Warmer temperatures and changing precipitation patterns
Rising temperatures and changing precipitation patterns have the potential to affect all types of infrastructure. With warmer temperatures, air moisture increases, giving rise to higher snow and ice loads, higher humidity (fog) and changes in snow-to-rain ratios. In parts of northern Canada, buildings, energy, and communications infrastructure were built for low snowfall conditions. Warmer temperatures are also resulting in shorter winter road seasons.
Communities dependant upon airport runways and all-weather roads are likely to experience increasing maintenance costs due to the gradual loss of structural integrity. Communications towers and energy transmission infrastructure located in remote permafrost areas are becoming more susceptible to the risk of failure, while energy pipelines built over permafrost terrain could be at risk of rupture and leakage.
Flooding and streamflow changes
The potential for increased flooding is a concern for northern communities located on floodplains. In addition to damages typically associated with flooding, these communities may also experience increased costs of maintaining river infrastructure because of increased silt buildup resulting from erosion due to increased flooding and runoff. Communities that rely on water transportation may find increased silting of navigation channels.
Sea-ice loss and coastal erosion
Coastal communities have observed the loss of sea ice, greater wave action, and the resulting accelerated erosion of coastlines. Coupled with land instability from permafrost degradation, intensified storm surges connected to higher sea levels, changes in storm intensities and tracks, and sea-ice loss may force communities to relocate buildings further inland.
Storms are likely to become more frequent and intense, and with wetter and warmer winters, northerners may be facing more severe snowstorms. Emerging evidence from communities points to the vulnerability of buildings to such heavy snow events. Over 20 per cent of public access buildings in the Northwest Territories are at risk or have been reinforced to account for increasing risk of roof collapse related to snowstorms. Rapid snowmelt, intense rainfall and other extreme weather events put stress on infrastructure such as roads and bridges.
A changing climate is likely to affect patterns of forest disturbances (such as wildfires and insect outbreaks); a major concern for community infrastructure below the tree line. The communications sector recognizes this is a serious issue for remote microwave stations. An interruption in communications services from wildfires is significant because of the lack of backup systems.