Protocol for High-Resolution Geospatial Analysis of Coastal Change in the Arctic Network of Parks

Coastal zones for Bering Land Bridge National Preserve (BELA) and Cape Krusenstern National Monument (CAKR) extend for over 450 km (280 miles), and include critical habitats, sensitive ecosystems, and cultural resources (including threatened archeological sites). These areas are sensitive to tundra bluff and beach erosion, shifting of tidal inlets, sediment deposition, changes to lagoon hydrology, loss of wetlands, and coastal flooding. Most of the coast has experienced erosion from 1950 to 2003. Where erosion has occurred, rates have averaged -0.5 m/yr (-1.7 ft/yr), reaching more than -3 m/yr (-10 ft/yr) – with shoreline retreat of tens to hundreds of meters (or feet). Continued, periodic inventory and monitoring of coastal change in the Arctic Network of Parks (ARCN) are necessary to address primary objectives concerning temporal trends, spatial variability, and impacts. This protocol provides background, a summary of historic coastal change, methodological rationale, data and operational guidelines, and stepwise procedures for geospatial analysis of coastal change (specifically, erosion and accretion of the shoreline). Future research should obtain new imagery, make sure it is properly orthorectified for required accuracy, and then: build a spatial database; digitize new shorelines; assess errors; analyze the shorelines using the USGS Digital Shoreline Analysis System (DSAS); and then synthesize and present the results as tables, graphs, and maps in reports. End results are precise, empirical, comprehensive, and representative. Future research can build upon previous data releases and use this protocol to answer the most pressing question: Is coastal erosion in BELA and CAKR increasing with sea-level rise and arctic warming?