Decreasing ice = increasing activity
As sea ice declines in the Arctic, activities such as trans-Arctic shipping, oil and gas extraction, mining, and tourism increase risks to people and ecosystems across the Arctic. Oil spills and other drilling- and maritime-related accidents can foul water and land, and increased traffic increases the risk of introducing invasive species. Greater levels of industrial activity also have the potential to alter the distribution of species, disrupt subsistence hunting and gathering activities, and create or exacerbate a range of social issues. At the same time, development activities may provide new economic opportunities for Arctic communities.
Energy production is the main driver of the State of Alaska’s economy, accounting for thousands of jobs and 80 percent of the state’s revenue. Reduced ice extent facilitates additional access to the substantial deposits of oil and natural gas under the seafloor in the Beaufort and Chukchi seas. A seasonally ice-free Arctic Ocean also increases concerns of sovereignty and security as it introduces the possibility of new international disputes and increased military traffic between the Pacific and Atlantic Oceans.
Threats to infrastructure
Climate change is likely to have significant impacts on existing infrastructure in the Arctic and on all future development in the region. Uneven sinking of the ground in response to thawing permafrost is causing underlying land to shift, increasing the potential to damage buildings, pipelines, roads, and airstrips across the region (see also Permafrost and Arctic Landscapes
The North Slope in Alaska is one of the most remote regions in the world: oil produced in this region travels through the Trans-Alaska Pipeline System to reach markets in the rest of the United States and beyond. Permafrost thaw is already affecting the Trans-Alaska Pipeline System: for instance, a vertical support member on one segment of the pipeline has tilted by seven degrees over a period of about three years. Permafrost thaw also affects the stability and load-bearing capacity of soils.
Uneven thawing will likely disrupt community water supplies and sewage systems, with negative effects on human health. The land of some rural communities is also threatened by erosion and coastal flooding; electrical distribution systems on these lands are also vulnerable to these impacts. Engineers are starting to improve structures to better withstand hazards of thawing permafrost, coastal erosion, and increased wildfires. They are also increasing their planning efforts to improve resilience to grid outages. Other practices to improve resilience of infrastructure include proactive vegetation management to prevent wildfire and installing protective barriers to protect grid equipment threatened by erosion.
Mining
Gold mining continues in Alaska, along with extraction of lead and zinc deposits from the Red Dog Mine, which contains two-thirds of U.S. zinc resources. Coal mining also occurs in several areas of the Arctic. Mining activities in the region sustain local economies and are an important contributor of raw materials to the global economy. The actual extraction processes are not likely to see a large impact from climate change. However, mines that utilize marine transport for their products may benefit from lower costs due to reduced sea-ice extent and a longer shipping season. Conversely, mining facilities with roads on permafrost are likely to experience higher maintenance costs as the permafrost thaws.
Projected increases in temperature, precipitation, and storm magnitude and frequency are very likely to increase the frequency of avalanches and landslides. In some areas, the probability of severe impacts on communities, roads, and railways from these events is very likely to increase. An increase in the frequency and magnitude of storms is very likely to lead to increased closures of roads, railways, and airports.
Transportation
In Alaska, permafrost damage to transportation infrastructure already costs $10 million in annual expenditures to protect and relocate roadways. 1 Less obvious damage from the frost heaves that result from more frequent freezing-thawing cycles reduces load-carrying capacity of roadways and decreases overall performance. Reduced sea ice along the coasts means less protection from waves, and more erosion along roads and railroads adjacent to the shore. Lastly, increased runoff from melting of glaciers and spring snow increases sediment transport and scour at bridges, further damaging land-based transportation infrastructure.
In recent years, temporary winter transportation routes have played an increasingly important role for community supply and industrial development in permafrost zones. These transportation corridors consist of ice roads that traverse frozen lakes, rivers, and tundra. In some cases, ice roads are constructed for one-time industrial mobilizations, such as oil and gas exploration activities. In other cases, permanent ice-road corridors have been established and are reopened each winter season.
Winter ice roads offer important advantages that include low cost and minimal impact to the environment. Oil and gas exploration can be conducted from these structures with very minimal ecological effects. Additionally, costs associated with construction and eventual removal of more permanent gravel roads or work pads can be avoided. Winter ice-road construction is affected by a number of climatic factors, including air temperature and snowfall. Climatic conditions also play a strong role in determining the opening and closing dates for winter road travel, although inspection techniques and load requirements, among other factors, are also important. Increased air temperature is very likely to have a negative impact on the duration of the winter road season.
Climate change could potentially result in beneficial effects on waterborne transportation. Global climate projections show that current summer ice-free conditions in the Northern Sea Route within the Arctic Ocean may increase from 20–30 days per year to about 90–100 days by 2080. 2 For ship travel from the North Pacific to northern Europe, the Northern Sea Route is 40 percent shorter than the Suez Canal Route. Additionally, reduced sea ice can also reduce ice accumulation on ships and docks, reduce ice jams in harbors, and reduce the likelihood of dangerous ice fog conditions.
Preparing for increased Arctic shipping
New ice-breaking ship designs are continually improving the efficiency of Arctic shipping. Growing evidence of climate change indicates that ice-free navigation seasons will probably be extended and thinner sea ice will probably reduce constraints on winter ship transits. Additional northern port capacity is critical to the success of Arctic shipping strategies associated with northern resource development and potential climate change. Difficulties related to freezing temperatures, snow accumulation, and long periods of darkness compound the challenges of geotechnical, structural, architectural, mechanical, electrical, transportation, and coastal engineering in designing and operating sea and river ports. Projected future reductions in sea ice extent are likely to improve access along the Northern Sea Route and the Northwest Passage. Projected longer periods of open water are likely to foster greater access to all coastal seas around the Arctic Basin. While voyages across the Arctic Ocean (over the pole) will likely become feasible this century, longer navigation seasons along the Arctic coasts are more likely.
Climate change is also affecting aviation facilities. Many airstrips are built on permafrost, especially in distant rural communities, and may require relocations and major repairs due to thawing. Because air transport is important for rural communities, climate change may have substantial impacts on how rural communities function. Many of the state’s rural communities depend exclusively on a local airstrip for transporting passengers and freight, including heating fuel. A significant number of airstrips in communities of southwest, northwest, and interior Alaska are built on permafrost and will require major repairs or complete relocation if their foundations thaw.
To avert some of the more costly effects of climate change on transportation, adaptation practices are needed. For most infrastructure, engineering designs that are more climate resilient can be implemented with rehabilitation and replacement cycles. A road rehabilitation cycle of 15 years allows engineers to adapt to changing conditions with each cycle. Incorporating adaption into rehabilitation cycles could save 10–45 percent of the expected costs of climate change. 3 For longer-lived infrastructure such as bridges, sensors are being used to monitor the extent of changing pressures and stresses on some structures, so structure rehabilitation can be implemented when a threshold is reached. These practices can enable timely and appropriate responses, even with the increased scouring expected with climate change.
The preceding text is excerpted and abridged from the following sources:
- Climate Change and the U.S. Energy Sector: Regional Vulnerabilities and Resilience Solutions.
- Larsen, P.H., S. Goldsmith, O. Smith, M.L. Wilson, K. Strzepek, P. Chinowsky, and B. Saylor (2008): Estimating future costs for Alaska public infrastructure at risk from climate change. Global Environmental Change, 18, 442–457.
- Potential Impacts of Climate Change on U.S. Transportation.
- Climate Change Impacts in the United States: The Third National Climate Assessment (Chapter 22: Alaska).
- Arctic Climate Impact Assessment.
- Climate Change, Permafrost, and Impacts on Civil Infrastructure.
- 1Chapin, F. S., III, S.F. Trainor, P. Cochran, H. Huntington, C. Markon, M. McCammon, A.D. McGuire, and M. Serreze (2014): Ch. 22: Alaska. Climate Change Impacts in the United States: The Third National Climate Assessment, J. M. Melillo, Terese (T.C.) Richmond, and G. W. Yohe, Eds., U.S. Global Change Research Program, 514–536, doi:10.7930/J00Z7150.
- 2ACIA (2005): Arctic Climate Impact Assessment. Cambridge University Press, 1042 pp.
- 3Larsen, P.H., S. Goldsmith, O. Smith, M.L. Wilson, K. Strzepek, P. Chinowsky, and B. Saylor (2008): Estimating future costs for Alaska public infrastructure at risk from climate change. Global Environmental Change, 18, 442–457.
Nancy Heise. Public domain, via Wikimedia Commons
Declining sea ice opens opportunities for shipping, oil and gas extraction, mining, and tourism. These activities can stimulate the economy, but they bring new risks to people and ecosystems across the Arctic.