Thursday, September 16, 2010

WyomingView interns present their research findings in the 2010 GIS in the Rockies Conference

WyomingView interns (spring 2010 semester) Paul Arendt and William (Bill) Gray presented their research findings in the 23rd annual GIS in the Rockies Conference in Loveland, CO.

Using Landsat images Paul Arendt (BA Geography) analyzed the spectral reflectance patterns of areas impacted by the Mountain pine beetle in the Medicine Bow National Forest, Wyoming.  He combined Landsat observations with aerial survey data collected by the US Forest Service to identify differences in the reflectance patterns of beetle infected (n=77) and non-infected (n=50) areas. He calculated Normalized Difference Vegetation Index (NDVI) and Tasseled Cap Wetness Index for these sites and found that both indices had lower values at affected sites and these differences were statistically significant (p < 0.01). Within the 77 beetle infected sites, the mean NDVI and Tasseled Cap wetness values were higher (p < 0.01) in the patchy lower forest (< 2567 m) in comparison to the subalpine lodgepole pine (>2568 m) forest.  Describing the value of this research, Paul commented "...this project served as an excellent introduction to the process of scientific research".

Bill Gray (MA Planning) used Landsat images acquired from 1984 through 2009 to map changes in the surface area of Ocean Lake in Freemont County, Wyoming. Using images acquired in spring and fall for 27 years, he mapped changes in the surface area and compared the within- and between-year variations.  His findings revealed that the lake's surface area in spring (2442 hectares) was less in comparison to the surface area in fall or autumn (2457 hectares).  The overall area showed a declining trend from 2536 ha (fall 1986) to 2392 ha (fall 2009).

Both studies were possible due to the availability of no-cost Landsat data.  Prior to the no-cost Landsat data era, purchasing 54 images that Bill Gray used in his study, would have cost him US$ 35,000 which would be beyond the reach of any graduate student.  "A unique aspect of this study is that it offers the end-user a technique to use the free archive of LandSat images in a time series for analysis..." said Bill Gray.

Every semester WyomingView offers internships to UW undergraduate and graduate students to work on projects that use remotely sensed data for addressing natural resource management issues in Wyoming.