Examples: Example 1

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Using Remote Sensing

  1. Obtaining
  2. Linking
  3. Subsetting
  4. Compositing
  5. False coloring
  6. Ratioing
  7. Supervised classification


Pre-post test

Example #1

Temporal Anlaysis:  Determining changes in land cover

         The images below are of the Cincinatti, Ohio area. The first image is March 2001, and the second image is Sept. 2000.  If you zoom in on the images, you can observe similarities and differences betweem the two images. These images use bands 542 for red, green, and blue, respectively. Note that there is higher reflectance in band 4, green, in Sept. than in March. Since vegetation returns a high reflectance in band 4, there is more vegetation ground cover in Sept than in March. Soil covered land surface returns a high reflectance in band 2, blue. Sediment in water also returns a high reflectance in band 2, blue. Note that the Ohio river has consistently high sediment in both images. In smaller rivers, the amount of water sediment is more heavily influenced by river banks and local run off. Often there is more river sediment in the spring because spring rains on bare slopes cause erosion to carry sediment to the river.  However, the small river located at the yellow lightening bolt indicator, has less sediment in March than September. Why? Look at the magenta color, combined red and blue colors. Moist ground returns a high reflectance in band 5, red. Magenta colored areas would be soil covered, band 2, and moist, band 5. Moist soil covered land is caused by precipitation. Therefore, the high river sediment content may be due to recent rainfall in Sept. Data from the weather underground site,

http://www.wunderground.com/ , shows that it had been raining, overcast and foggy for the previously 6 days in Sept. This may account for the high reflectance in band 4, vegetation mentioned earlier. Golf courses, appearing as curvy nests of worms will be well watered in both seasons, and return high reflectance in band 4.