Haida Gwaii
The average air temperatures in Haida Gwaii may increase by 1.4°C by the 2050s and by 2.2°C by the 2080s. The number of growing degree days will increase and frost free days will increase, as winter minimum temperatures may increase by up to 4-9°C by 2080 [10,42,70,71,73]. The average annual precipitation is likely to increase by 7% on average by the 2050s, and by closer to 9% by the 2080s ([73]; see Sub-regional Table, Haida Gwaii). Rising air temperatures and changing precipitation patterns are likely to threaten fisheries related tourism, yet may also provide potential benefits to the tourist season as the summer becomes warmer and longer. Increasing precipitation poses flooding risks to local communities in Haida Gwaii, which may affect access to traditional food gathering places. Increased spring runoff could damage coastal infrastructure, especially in the case of earlier freshet floods.
Sea level rise is projected to impact Haida Gwaii, especially low-lying areas along the east coast of Graham Island [21,25,85]. The coast of Haida Gwaii, especially the east coast of Graham Island, is highly dynamic; with sea level rise, the area is likely to erode as beaches and sand dunes migrate onshore. This sediment transfer is likely to cause shoreline retreat along coastal beaches (Walker and Barrie 2006). Previous projections by the Geological Survey of Canada have identified that area as among the top 3% most sensitive coastlines in Canada, due to the combination of low lying shoreline and easily eroded shorelines with large tidal ranges [69,107]. The ecosystems of Haida Gwaii are highly exposed to rising sea levels and increasing sea surface temperatures. Rising sea levels increase the risk of permanent inundation of important coastal habitats and can lead to loss of wetlands which are critical for bird and fish species. In addition, increasing sea surface temperatures are likely to diminish ecosystem health and alter coastal habitat composition [6]. There are also many cultural and historic sites that may be affected by rising sea levels based on a recent shoreline sensitivity analysis (see Haida Gwaii Archaeological Sites Shoreline Sensitivity Map).
Extreme storms and associated storm surge events are expected to intensify in this region due to the cumulative impacts of El Niño, the PDO, and sea level rise [69]. Previous El Niño events led to sea level rise and erosion along the same shoreline, and high water levels have since increased significantly [25]. Increasing winter winds are projected to increase seasonal currents and eddies near Rose Spit, Middle Bank, and Goose Island Bank [21]
Climate change impacts on fisheries in the area of the Queen Charlotte basin are somewhat uncertain [25]. While projections suggest declining species abundance and changing species compositions [92], the effects of warmer waters, altered production regimes, and exotic species have not yet produced obvious declines of herring and salmon in this area [25].
Climate change will impact the social, economic and environmental exposure of Haida Gwaii’s coastal communities. Particularly, sea level rise, and wind, wave and storms will have the highest direct impacts. Indirectly, changes in the ecosystems and fisheries and aquaculture will result in negative social and economic impacts on Haida Gwaii communities due to the high dependence to resource based life. Coastal communities and cultural and historical sites along the low-lying coastal areas of Haida Gwaii are the most exposed to rising sea levels, and winds, waves and storms. This is due to the increased likelihood of coastal flooding and erosion, and increased frequency, strength, and duration of storms and wind/wave action [31,42,107]. Increasing maintenance and insurance costs associated with the sea level rise and storm damages will also affect all Haida Gwaii communities [25].
Due to its geographic positioning, Haida Gwaii highly depends on its marine infrastructure for delivery of and access to goods and services, fishing and harvesting practices, and provisioning of utilities. Marine infrastructure in Haida Gwaii is increasingly exposed to climate change impacts, particularly to rising sea levels, and to increasing wave and wind actions from storms. The risk of marine transportation interruption is increasing due to increase in intensity, frequency and duration of storms, which will directly impact the delivery of goods and services, and access to the mainland [25].
Besides the marine transportation links and lanes, the infrastructure that supports the marine and land transportation is also likely to be affected by rising sea levels and heavy wind and wave actions. For example, the likelihood of damage to fixed coastal infrastructures, such as the Sandspit Airport, is likely to increase over time [74]. In addition, roads, utilities, power, communication, and flood protection infrastructures will experience inundation and/or structural damages with the increased risk of flooding, erosion and damage caused by rising sea levels, and wind and wave actions [25,42,113].
