British Columbia and Alaska are two regions of the world that are home thousands of glaciers of varying types (Vaughn et al., 2013). Land terminating glaciers in Southern British Columbia to tidewater glaciers in the Inside Passage, Southcentral, and Southwest regions of Alaska are thinning and receding causing a slew of literal “downstream” effects. This region, the Pacific Northwest region of North America, contains some of the least anthropogenically impacted ecosystems in the world, yet they are reaping the devastating effects of a warming climate and a warming climate (Romero-Lankao et al., 2014). In British Columbia, 3% of the landmass (30,000 sq. km) is covered by glaciers where they act as frozen freshwater reservoirs that provide runoff during summer and early autumn after all the snow has melted. Glaciers provide a large source of renewable energy, help sustain ecosystems, and provide a boost to the tourism economy of both the United States and Canada. (Moore et al., 2009).
Whistler Blackcomb, BC
Alaska is home to 23,112 glaciers covering approximately 89,267 sq. km of land. Western Canada and the US have 15,073 glaciers covering 14,503.5 sq. km (Vaughn et al., 2013). In Alaska, –570 ± 200 kg/sq. m is being lost whereas –930 ± 230 kg/ sq. m is being lost in Western Canada and the US.
The terminus of glaciers is a natural process. Glaciers slowly move downhill due to the natural forces of gravity (Moore et al., 2009). Higher elevation glaciers that can typically be found in southern/warmer climates are, in most cases, land terminating glaciers meaning that a drainage stream is found at the end of a glacier (United States Geological Service, 2013). Lake terminating glaciers occur when the tongue of the glacier is met by a lake that has formed in a basin as a result of glacial erosion (Moyer et al., 2016). The glacier calves into the lake, often in dramatic fashion, creating a positive feedback thus accelerating the rate of glacial melt due due the increased glacial flow rate (Moyer et al., 2016). Where the ocean meets the tongue of the glacier is a tidewater glacier. These also calve into the water, often on a larger scale than lake terminating with a slightly more significant positive feedback system due to the influence of the oceans, also accelerating the rate of ice flow (USGS, 2013; Moyer et al., 2016).
Glaciers melt at different rates as due to unique factors including; mass, density, velocity, age, rates of accumulation and ablation in combination with other factors. This makes it difficult to quantify which types of glaciers melt more quickly.
Glacier surface elevation changes in the Yakutat region and Glacier Bay region shown to the left are: average rate of volume loss is 16.7 ± 4.4 km3/yr. (Larsen et al., 2007)
Exposure and Vulnerability
Impacts of Glacial Recession
Warming leads to longer melt seasons
Seasonally earlier peak melt
Short term increased streamflow
Long term decreased streamflow
Change in stream dynamics
Sea level rise
Long-term Downstream Effects and Contributions to Sea Level Rise
Perhaps the most obvious long-term implication of melting glaciers is the disappearance of a consistent and reliable water source (Carey et al., 2017). Glaciers act as a reservoir for mountain communities, and the reservoir’s are quite simply, disappearing. The reliable, season long water source will no longer be dependable as the glaciers come to terminus.
Although British Columbia and Alaska may not have the largest population of glaciers in comparison to the rest of the world, they are making a significant contribution to sea level rise (Arendt et al., 2002). In fact, the glaciers along the Pacific Coast of North America have had an unprecedented contribution to rising sea levels (Arendt et al., 2009). Small-aircraft laser altimeter data show a rapid reductions of ice in Alaska and British Columbia contributing in the past 50 years more to global sea level rise than the Greenland ice-sheet (Larsen et al., 2007). An estimated 9% of sea level rise over those fifty years can be contributed to glacial melt in Alaska (Arendt et al., 2002). The ice mass loss contributed directly to the rise of sea levels.
The estimated net average rate of ice loss is 16.7 ± 4.4 cubed km /yr, which is equivalent to contributing 0.04 ± 0.01 mm/yr to global sea level rise (Larsen et al., 2007).
Short-Term Downstream Effects
The current warming trend leads to shorter winters and longer summers, resulting in a shorter amount of time for snowfall and a longer melt season. Anthropogenic climate change causes snow-dominated streams and rivers in western North America to peak earlier in snowmelt runoff (Barnett et al., 2008; Das et al., 2011; Romero-Lankao et al., 2014).
Shorter and warmer winters have very consequential impacts on the protection of glaciers. The winter months allow for snow to accumulate and act as a protective barrier over the glacier for the warm summer months. Winter precipitation directly impacts summer melt: years with high winter snowfall tend to have snow cover enduring late into the summer keeping surface albedo high and thereby reducing melt. (Moore et al., 2009)
There is an obvious direct correlation between the arrival of spring and the melting of the snowpack, but the earlier melting of the snowpack leads to an earlier streamflow maximum in the glacier-fed watersheds. Even though precipitation intensity may not change, these effects shift the peak river runoff to winter and early spring, which is not when waters is needed the most in summer and autumn. The majority of the winter runoff run directly into the oceans due to insufficiencies in storage capacity. In regions that fed by glaciers and alpine snowpack, peak streamflow could come up to a month sooner by the year 2050. As a result, the earlier streamflow further intensifies summer dryness and heat (Barnett et al., 2005).
Impacts on Mountain and Skiing Communities
- Mountain communities often rely on glacial streams for agriculture irrigation, livestock, hydroelectricity, recreation, and drinking water (Carey et al., 2017). The changes in timing and quantity present major societal and economic challenges for these communities.
- Aquatic species accustomed to and suited to their stream environments will likely have no other option than to adapt to changing stream compositions (Carey et al., 2017)
- Migratory and federally protected aquatic species pose an additional challenge, especially with river systems that generate hydroelectricity. A major decision will have to be made in the near future in order to accommodate hydroelectricity production and protected fish species with decreased water availability (Barnett et al., 2005).
- Many ski resorts across the world rely extensively on the survival of glaciers in order to maintain resort operations. Resorts with alpine terrain, many on glaciers, have been dealing with significant reductions to their glaciers as well as snowfall.
- Ski resorts in British Columbia have seen the protective snowpack layer disappear much earlier in the summer, leaving the glacier directly exposed for an extended period of the summer. The rate of ablation is far higher for the bare glacier than the seasonal snowpack.
- The retreat of glaciers in Alaska is leaving much less terrain for helicopter and snowcat skiing operations. These businesses are some of the most profitable businesses in Alaska.
- Whistler Blackcomb's summer skiing operations take place on the Horstman and Blackcomb glacier through the end of July and are very profitable for the resort and surrounding and supporting small businesses, but their operations have been cut short in recent years due to below average snowfall along with high spring and summer temperatures, resulting in serious economic impacts.
Adapting to Create Resilience
The relationship between ski resort and glacier can, in some cases, be mutualistic. Artificial snow production and slope maintenance can help glaciers by reducing the albedo effect and keeping adequate snow cover over the glacier (Fischer et al., 2016). Resorts have begun to increase snowmaking operations as well as glacier preserving efforts in order to help retain their glaciated terrain and overall economic sustainability.
About the Author
In 2017 Nick Zachara's was an Economics - Environmental Studies Combined Major and a Business in the Liberal Arts major at St. Lawrence University. He is passionate about the outdoors, photography and the environment - always looking for new places to explore and recreate in, and expand his personal and professional networks in the ski industry. In the summer of 2016 photographed top professionals in the freeski community at Momentum Ski camps as a photography and social media intern. This narrative was created for Dr. Jon Rosales' Adaptation to Climate Change course.
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