Inventory and Monitoring of Coastal Erosion
for Alaska's Arctic Network of Parks
Shoreline erosion is one of the most rapid and observable changes in Arctic environments. Protected by sea ice for much of the year, coastal ecosystems are sensitive to climate change and environmental stressors such as: permafrost melting, sea-level rise, the frequency and intensity of storms, and the length of the summer ice-free season. With losses on the order of about 1-10 m/yr (3-30 ft/yr), coastal erosion in the Arctic threatens archeological sites and a variety of nearshore marine, terrestrial, and freshwater habitats.
In 2005, the National Park Service initiated a study on coastal erosion for two parks in northwest Alaska:
Bering Land Bridge National Preserve (BELA) and Cape Krusenstern National Monument (CAKR). The study is coordinated through the Inventory and Monitoring Program, with the mission to "collect, compile, and synthesize scientific information about the arctic nework of parks to facilitate their preservation, unimpaired, for future generations." Furthermore, the "broad-based, scientifically sound information ... will have multiple applications for management decision-making, research, education, and promoting public understanding of park resources."
In collaboration with researchers from the University of Colorado, this study has taken advantage of Geographic Information Systems (GIS) and high-resolution imagery. Orthophoto mosaics have been assembled with resolution as good as 0.6 m (2.0 ft). Across this broad area, shorelines have been analyzed with "timeslices" from approximately 1950, 1980, and 2003. As the analysis continues, the aerial photography will provide the basis to collect baseline data, determine long-term trends, and understand how landscape components interact and change over time.
An informal workshop -- with invited talks and hands-on activities -- was held Oct. 17, 2008 to assess the potential of "High-Resolution Imagery for Analysis of Environmental Change in Northern Alaska."
High-resolution imagery is now available for the coastal and nearshore areas of Bering Land Bridge National Preserve (BELA) and Cape Krusenstern National Monument (CAKR). The imagery consists of orthorectified digital photography — at 1 m or better resolution — for three timeslices: from 2003, approx. 1980, and approx. 1950. Beyond our study of coastal erosion, the orthoimagery is available to the public, and will be useful for detection of a broad range of environmental changes. For more information, see:
- Manley et al., 2008: 38th International Arctic Workshop, University of Colorado at Boulder, March 2008.
- Manley et al., 2007:
Arctic Coastal Zones at Risk, Scientific Workshop on the Impact of Global Climate Change on the Arctic Coastal Zones, Tromsø, Norway, Oct. 2007.
- Manley et al., 2007: Arctic Coastal Dynamics - Report of the 6th International Workshop, Arctic Centre, Univ. of Groningen (Netherlands). Rep. Polar and Marine Research.
- Jordan et al., 2007: Arctic Coastal Dynamics - Report of the 6th International Workshop, Arctic Centre, Univ. of Groningen (Netherlands). Rep. Polar and Marine Research.
- Manley et al., 2006: Eos Trans. AGU.
"Fly" across the coastal environments of Bering Land Bridge NP (24 MB!) and Cape Krusenstern NM (7 MB). QuickTime required.
Questions or comments:
William Manley, University of Colorado
Jim Lawler, National Park Service