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Understanding spectral changes in surface reflectance in relation to burn severity in tussock tundra
Tatiana
Loboda, University Maryland, tloboda@hermes.geog.umd.edu
(Presenter)
Rapid warming of high northern latitudes has led to a noticeable increase to fire occurrence in tundra in the past decade. While fire is a major component of boreal ecosystem functioning in Alaska, tundra fires have been rare events in the past. In the last 5 years a number of large fire events have been detected in Alaskan tundra prompting an increased interested in studying fire impact on tundra ecosystem functioning and developing methods for assessing fire impact from satellite imagery. In this project, funded by the NASA Terrestrial Ecology and Ecosystems program, we track changes in spectral properties of tundra surface using Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) within the Kaluktavik River fire event of 2010 in Noatak National Preserve in Alaska. A field team visited the Kaluktavik River fire site in August 2011 to develop a field-based assessment of burn severity which is subsequently used to test existing and assess new methods for mapping burn severity in tussock tundra from moderate-resolution (30 m) imagery. Existing field assessment methods have not been well related to remote sensing-derived burn severity in Alaskan tundra ecosystems by previous studies, and few examples of tundra fire were available to test those approaches. Our main goal in the presented study is to develop an understanding of spectral signature of fire in Alaska and its dynamics and how it is related to field-based measurements of burn severity in tussock tundra. We explore temporal evolution of burn signature for individual Landsat TM and ETM+ bands and their combinations including NDVI, NDWI, NBR, short-wave and infra-red albedo, Tasseled Cap parameters, and other variables. Presentation Type: Poster Session: Global Change Impact & Vulnerability (Tue 11:30 AM) Associated Project(s):
Poster Location ID: 224
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