New USGS study measures North Slope shoreline losses
FRISCO — In the eternal battle between land and sea, the sea appears to be winning in northern Alaska, where much of the coastline is retreating at a rate of more than three feet per year, according to a new study by the U.S. Geological Survey.
The region has some of the highest shoreline erosion rates in the world, according to the research, which analyzed more than 50 years worth of measurements.
“Coastal erosion along the Arctic coast of Alaska is threatening Native Alaskan villages, sensitive ecosystems, energy and defense related infrastructure, and large tracts of Native Alaskan, State, and Federally managed land,” said Suzette Kimball, acting director of the USGS.
Scientists studied more than 1600 kilometers of the Alaskan coast between the U.S. Canadian border and Icy Cape and found the average rate of shoreline change exceeded 1.4 meters. In the most extreme case, one beach was eroding at the rate of 18.6 meters per year.
“This report provides invaluable objective data to help native communities, scientists and land managers understand natural changes and human impacts on the Alaskan coast,” said Ann Gibbs, USGS Geologist and lead author of the new report.
Coastlines change in response to a variety of factors, including changes in the amount of available sediment, storm impacts, sea-level rise and human activities. How much a coast erodes or expands in any given location is due to some combination of these factors, which vary from place to place.
“There is increasing need for this kind of comprehensive assessment in all coastal environments to guide managed response to sea-level rise and storm impacts,” said Dr. Bruce Richmond of the USGS. “It is very difficult to predict what may happen in the future without a solid understanding of what has happened in the past. Comprehensive regional studies such as this are an important tool to better understand coastal change. ”
There is no widely accepted standard for analyzing shoreline change. The impetus behind the National Assessment project was to develop a standardized method of measuring changes in shoreline position that is consistent on all coasts of the country. The goal was to facilitate the process of periodically and systematically updating the results in a consistent manner.
The report, titled “National Assessment of Shoreline Change: Historical Shoreline Change Along the North Coast of Alaska, U.S.-Canadian Border to Icy,” is the 8th Long-Term Coastal Change report produced as part of the USGS’s National Assessment of Coastal Change Hazards project.