Methods
Utilizing the United States Geological Survey (USGS) Earth Explorer, online resources for Landsat 5, and Landsat 8 data from the information clearing house, digital images were produced using Idrisi image processing GIS software. Constructed images were processed, enhanced, and analyzed using multiple methods such Landsat 5 and 8 band combinations.
Band combinations were specifically chosen to best represent water level fluctuation and dry soil/water boundaries to indicate any change in shoreline within Shasta Lake over time. Bands, 4,5,3 were color coded as red, green, and blue (RGB). This combination of near-IR (Band 4), mid-IR (Band 5), and red (Band 3) was selected to provide strong definition of soil/water boundaries with great detail. The 3,4,5 band combination was selected as an overall, big picture assessment to identify any significant change in water level. This band combination provides a stark contrast between water and soil/water boundaries.
Band combinations were specifically chosen to best represent water level fluctuation and dry soil/water boundaries to indicate any change in shoreline within Shasta Lake over time. Bands, 4,5,3 were color coded as red, green, and blue (RGB). This combination of near-IR (Band 4), mid-IR (Band 5), and red (Band 3) was selected to provide strong definition of soil/water boundaries with great detail. The 3,4,5 band combination was selected as an overall, big picture assessment to identify any significant change in water level. This band combination provides a stark contrast between water and soil/water boundaries.
Color Composite Procedures
- 1) Open USGS Earth Explorer clearinghouse with internet browser: http://earthexplorer.usgs.gov/
- 2) Identify area of reasearch: 40.7602 N, 122.3719 W as approximate center of study area
- 3) Access data sets from Landsat Archive: Landsat 8 OLI/TIRS, Landsat7 ETM, and Landsat 5 TM
- 4) Landsat data files were downloaded from USGS Earth Explorer
- 5) Data files were then extracted using windows 7 Zip and converted from tar.gz to .tar format
- 6) Extracted files were imported into Idrisi: File - import - Government/Data Provider Formats - Landsat ETM
- 7) Selected data files are then converted from geotiff format to Idrisi image files
- 8) Designate bands to RGB color assignments for best use (4,5,3 and 3,4,5 described above)
- 9) Create color composite from designated band assignments
- 10) Window the color composite, add appropriate map components
This webpage was created for use in ES 771 Remote Sensing, Emporia State University. Spring 2015. Dr. James S. Aber, Professor. Authored by Corey Miller, Graduate Student. Header image acquired online from USGS Earth Explorer.