Abstract
Geospatial Observations of Coastal Change in Northwestern Alaska Track: Ocean, Coastal, and Marine Resources Author(s): William Manley, James Jordan, Eric Parrish, Diane Sanzone, Leanne Lestak, Owen Mason Coastal environments at high latitudes are experiencing rapid change. To understand impacts for national parks in northwestern Alaska, a collaborative study has documented changes to beaches, barriers, lagoons, and tundra bluffs in the southeast Chukchi Sea. Aerial photographs for ca. 1950, ca. 1980, and 2003 were orthorectified at 0.6-1.0 m. Digitized shorelines and blufflines were then analyzed with the USGS DSAS extension to ArcGIS. The resulting patterns of erosion and accretion exhibit complex variability related to environmental forcing, morphologies, and processes. Most of the 400-km-long coast has experienced erosion, with long-term average rates of 0-3 m/yr. Impacts include beach and bluff retreat, overwash deposition, migration or closure of inlets and lagoons, capture of thaw-lake basins, and release of sediment and organic carbon to nearshore waters. Coastal ecosystems in the region appear to be sensitive to storm events, increasing temperatures, permafrost melting, sea-level rise, and increasing length of the ice-free season. William Manley University of Colorado INSTAAR 450 UCB Boulder , CO 80309-0450 US Phone: 303-735-1300 E-mail: william.manley@colorado.edu James Jordan Antioch University New England Department of Environmental Studies 40 Avon Streen Keene , NH 03431-3552 US Phone: 603-283-2339 E-mail: James_Jordan@antiochne.edu Eric Parrish University of Colorado INSTAAR 450 UCB Boulder , CO 80309-0450 US Phone: 303-492-5802 E-mail: Eric.Parrish@colorado.edu Diane Sanzone National Park Service Arctic Network 4175 Geist Road Fairbanks , AK 99709-3420 US Phone: 907-455-0626 E-mail: diane_sanzone@nps.gov Leanne Lestak University of Colorado INSTAAR 450 UCB Boulder , CO 80309-0450 US Phone: 303-492-5802 E-mail: Leanne.Lestak@colorado.edu Owen Mason Geology and Archaeology in Alaska P.O. Box 91554 Anchorage , AK 99509-1554 US Phone: 907-336-0092 E-mail: geoarch@ptialaska.net |
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