Classification of northern Alaska coastal morphology from high-resolution oblique photography
Abstract
Geo-located oblique photography and videography collected during the summers of 2006 and 2009 is used to develop a modern coastal classification scheme for the north coast of Alaska from Demarcation Point near the U.S. - Canada border to Cape Sabine on the Chukchi Sea coast. The arctic coast of Alaska is undergoing widespread change highlighted by localized areas exhibiting extreme rates of coastal erosion. The purpose of this study is to build upon previous classification efforts using recent high-resolution photography as part of a larger research effort to document historical shoreline change. Primary coastal landforms that are mapped include tundra bluffs, barrier islands, deltas, lagoons, and embayments. These landforms are further characterized by their elevation, exposure to waves and currents, sediment type, and small-scale morphological features. High-resolution images are particularly useful for discriminating coastal features such as the presence and/or absence of slumps, erosional scarps, notches and collapsed visors, permafrost layers, bluff protection structures, and tundra vegetation. Other coastal features identified include ice-push ridges on the foreshore, debris wrack lines indicating marine inundation and areas of overwash, and areas of human modification. Coastal plain features such as patterned tundra, inundated tundra, thermokarst lakes, and drainage systems are also noted where present. Morphological features characteristic of erosion, such as scarps, slumps, and collapsed visors, are widespread and indicate large segments of the study area are undergoing coastal land loss. The oblique imagery will be further used to help ground-truth features mapped as part of an airborne lidar topographic mapping survey to be conducted in the late summer of 2009.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2009
- Bibcode:
- 2009AGUFMEP43B0662R
- Keywords:
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- 1625 GLOBAL CHANGE / Geomorphology and weathering;
- 3020 MARINE GEOLOGY AND GEOPHYSICS / Littoral processes;
- 4217 OCEANOGRAPHY: GENERAL / Coastal processes;
- 9315 GEOGRAPHIC LOCATION / Arctic region