William F. Manley, Leanne R. Lestak, and Eric G. Parrish INSTAAR, University of Colorado High-Resolution Orthorectified Imagery for Three Target Areas.

William F. Manley, Leanne R. Lestak, and Eric G. ParrishINSTAAR, University of Colorado

High-Resolution Orthorectified Imagery for Three Target Areas in Lake Clark National Park

and Preserve (LACL), Southwest Alaska

Introduction

This powerpoint presentation is a visual overview of high-resolution orthorectified imagery that is now available for the coastal and nearshore areas of three target areas within Lake Clark National Park and Preserve (LACL): Glacier Spit, Silver Salmon, and Tuxedni Bay.

The imagery was completed as part of a pilot study by the University of Colorado in collaboration with the Southwest Alaska Network Inventory and Monitoring Program. Beyond analysis of coastal change, the imagery will be of interest to land managers, scientists, and others for observation and study of natural features and ecosystems.

Orthorectified Aerial Photography

1993

2004-2006 IKONOS(available separately)

ca. 1950

1978

Goals

The three, co-registered “timeslices” of imagery complement recent IKONOS acquisitions, and greatly improve the resolution, accuracy, and temporal extent of the previously georectified LACL coastal atlas. The imagery will be helpful for a broad range of studies, and to detect change in:

• cultural resources and archeological sites

• ecosystem components such as coastal zones, wetlands, geology, soils, lake & stream hydrology, and vegetation assemblages

• marine, terrestrial, and freshwater habitats for a variety of animals

The imagery assists the goals of the Southwest Alaska Network for inventory and monitoring of natural resources.

Study Area

• coastal LACL

• three target areas with importance for resource management and other I&M studies

1954-1957

• 5 frames• Black and White• 1:43,000• 60 cm resolution• 15.5 m accuracy

1978

• 3 frames• Color IR• 1:65,000• 1.0 m resolution• 17.3 m accuracy

1993

• 8 frames• Black and White• 1:24,000• 30 cm resolution• 7.2 m accuracy• low tide (~MLLW)

Glacier Spit1957

tidal channel dynamics

beach accretion

wetland changes

forest expansion

Glacier Spit1978

tidal channel dynamics

beach accretion

wetland changes

forest expansion

Glacier Spit1993

tidal channel dynamics

beach accretion

wetland changes

forest expansion

Glacier Spit2004 (IKONOS)

tidal channel dynamics

forest expansion

beach accretion

wetland changes

Silver Salmon1957

coastalerosion

forest expansion

wetland changes

tidal channeldynamics

Silver Salmon1978

coastalerosion

forest expansion

wetland changes

tidal channeldynamics

Silver Salmon1993

coastalerosion

forest expansion

wetland changes

tidal channeldynamics

Silver Salmon2004 (IKONOS)

tidal channeldynamics forest expansion

coastalerosion

wetland changes

Tuxedni Bay1954

intertidal flat

Tuxedni Bay1978

expansion of wetland vegetation after uplift of 1964 earthquake

Tuxedni Bay1993

wetland

changes

Tuxedni Bay2006 (IKONOS)

wetland

changes

Tuxedni Bay1978(Perspective views are also possible)

Methods Each frame fully orthorectified to the IKONOS reference imagery. Procedure after extensive testing:

• ERDAS Imagine, with:• air photo camera models• IKONOS stereo Digital Terrain Model• available camera calibration information• image-to-image control points spread across frame

Horizontal accuracy for each frame then quantified with independent check points. Errors can be reduced further for small areas.

• 30 cm resolution• 3.4 m accuracy

• 2 m resolution• 260 m accuracy

Comparison at Glacier Spit

Previously Georectified Coastal Atlas This Data Release

Available to the Public:

• readme file• orthoimagery for 1993, 1978, and ca. 1950• index map layers• FGDC metadata• on 2 DVD’s

Contact:Southwest Alaska Network Data ManagerNational Park ServiceSouthwest Alaska Inventory and Monitoring Program240 West 5th AvenueAnchorage, AK [email protected]

Questions?:

Southwest Alaska Network Data ManagerNational Park ServiceSouthwest Alaska Network Inventory and Monitoring Program240 West 5th AvenueAnchorage, AK [email protected]

William Manley, PhDInstitute of Arctic and Alpine Research (INSTAAR)University of Colorado1560 30th StreetBoulder, CO [email protected]

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