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Climate Change's Effects on Alaska's Coastlines

Under global warming scenarios, the risk of entire communities disappearing due to coastal erosion is greatly increased,
reports Michel Mesquita in the AGU Newsletter

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Coastal erosion is a significant problem in the Arctic. The Arctic coastlines are highly variable and their dynamics are a function of environmental forcing (wind, waves, sea-level changes, sea-ice, etc.), geology, permafrost and other elements [Rachold et al., 2005]. Under global warming scenarios, the risk of entire communities disappearing due to coastal erosion is greatly increased. The cost to move an entire village or town could devastate the local economy. Therefore, a better understanding of global warming effects and atmospheric forcing on the coast is essential.

According to Dr. Atkinson, Assistant Professor at the University of Alaska Fairbanks (UAF/IARC), heavy storms regularly hit most coastal regions of Alaska. Most of Alaska (80%) is ocean or river coastal. A lot of people and economic and subsistence activity are at risk due to erosion, inundation (floods and rising sea levels) and shipping accidents (under extreme weather conditions). The Cougar Ace ship accident in 2006, transporting nearly 4,800 Mazda cars and trucks off the coast of Alaska, was an example of how devastating such accidents can be. According to a USA Today article on the incident, the loss of one container with small parts could shut down a  manufacturing line [Carty, 2006]. The climate change trends that dominate coastal susceptibility are: loss of sea ice, when the coast is ice free, it gets exposed to high winds and storm events and the risk of erosion is higher; melting of permafrost, which weakens coastal zones; and sea level rise, which is not the primary player for Alaska in the short term.

The town of Kivalina (www.kivalinacity.com) has filed a global warming-related lawsuit against nine oil companies, 14 power companies and one cocompany. Kivalina is located in the state of Alaska, northwest of Kotzebue (see map below). According to the 2000 U.S. Census Bureau Summary File 1, the town has 377 inhabitants, 80 housing units and almost 10 km2 of total area, more than half of which is water. Kivalina is suing the 24 companies for emissions causing climate change. Due to global warming, the coastal erosion problems there may cause the town to disappear in the near future (see box below –“Interview with the Kivalina City Council Administrator”). The lawsuit was filed in Federal Court in San Francisco on February 26, 2008 and it is still ongoing. It mentions that the U.S. Army Corps of Engineers and the U.S. Government Accountability Office have estimated the cost of relocating the town at $95 to $400 million.

The town of Kivalina, located at 67°43′8″N, 164°29′32″W.
Source: Wikipedia

 

Shishmaref is another example where coastal erosion is threatening a community (see above picture). According to the Shishmaref Relocation website (www.shishmarefrelocation.com ), the community has established an erosion and relocation coalition to facilitate the decision to remain at its present location or to relocate. The community is in favor of the latter.

In an effort to understand the Arctic coastal erosion processes, the Arctic Coastal Dynamics project (ACD) was created. The main interests of ACD are:1) to improve wind and bathymetry databases; 2) to improve the understanding of coastal erosion processes; and 3) to understand the impacts of coastal erosion on humans and biological systems. The ACD is working with many interna- tional scientists toward developing a broadly applicable coastal erosion model. The circumarctic coastal zones are adjacent to shallow continental shelves. To get accurate model results, detailed input bathymetry and wind data are still needed. Improved data collection and the new model will help us understand the changes that global warming could bring to the Arctic. 

Atkinson [2005] reported that, “Coastal regions are particularly sensitive to the impact of high magnitude weather events. These areas receive storm energy in a concentrated form, due to a transfer of momentum from wind to water, which focuses the wind energy into waves, delivering it more effectively into
the coastal zone. ” Therefore, it is necessary to better understand the effects of storm tracks, wind activity and global warming for accurate projections of change along the Arctic coastlines. It is hoped that the ACD efforts and the Arctic  research work being conducted in many universities may shed some light on understanding the future Arctic condition.Janet
Mitchell, the Kivalina City Council Administrator, for the interview and also Dr. Atkinson for the invaluable comments on the coastal erosion problems in the Arctic.

The lawsuit can be downloaded from:
http://climatelaw.org/cases/country/us/kivalin
a/Kivalina%20Complaint.pdf

References:

Atkinson, D. E. (2005), Observed Storminess Patterns and Trends in the Circum-Arctic Coastal Regime, Geo-Marine Letters, 25 (2-3), 98-109.

Carty, S. S. (2006), When Cargo Gets Lost at Sea Firms Can See Big Shortages, Losses, USA Today, URL:
http://www.usatoday.com/money/world/2
006-08-03-cargo-problems-usat_x.htm


Rachold, V., et al. (2005), Reports on Polar and Marine Research, Berichte zur Polar und Meeresforschung, 506, Alfred Wegener Institute, Bremerhaven, 1-20.

Zhang, K., et al. (2004), Global Warming and Coastal Erosion, Climate Change, 64, 41- 48.