Perspective View

Coastal Orthoimagery for the
Southwest Alaska Network of Parks

Shoreline change was identified as an important "vital sign" for the National Park Service's Southwest Alaska Network (SWAN). Land loss or gain at the marine edge has important ecological — as well as jurisdictional — implications. The physical configuration of the SWAN coastal shoreline is dynamic and constantly changing due to coastal erosion and accretion from natural events, such as storm-driven waves, high tides, nearshore currents, rainfall and runoff, landslides, and earthquakes. Changes in the position of the shoreline affect the composition, relative abundance, and distribution of coastal habitats.

In collaboration with the SWAN Inventory and Monitoring Program, researchers at the University of Colorado at Boulder have begun to develop a strategy for long-term shoreline change analysis based on a time series of orthorectified aerial photographs extending as far back as the 1950’s. High-resolution orthoimagery was recently created for three target areas in Lake Clark National Park and Preserve (see below). A companion report will soon be released, including: an assessment of coastal imagery for the entire SWAN parks; a quality review of the recent data release; preliminary analysis of shoreline change for the Silver Salmon area; and recommendations for additional study.

Beyond analysis of coastal change, the orthoimagery will be of use for a broad range of studies and other "vital signs" related to environmental change.

 Data Release

High-resolution imagery is now available for the coastal and nearshore areas of three target areas in Lake Clark National Park and Preserve. The imagery consists of orthorectified historic photography — at 1 m or better resolution — for three timeslices: from 1993, 1978, and approx. 1950. The orthoimagery complements recent IKONOS satellite acquisitions, and is available to the public. Beyond our study of coastal erosion, the imagery will be useful for detection of a broad range of environmental changes. For more information, see:

      Related Links

    Questions or comments:

William Manley, University of Colorado

Michael Shephard, National Park Service