Example of dense vegetation causing false detection of vertical change

Example of dense vegetation causing false detection of vertical change. The images are NED shaded relief (upper left), SRTM shaded relief (upper right), SRTM NED difference grid (lower left; red = significant increase in elevation), and areas of significant differences (outlined in yellow) overlaid on a color infrared rendition of a Landsat image (lower right). There are no actual topographic changes in this area in western Kentucky. Note that the areas of significant differences coincide with areas of dense bottomland and upland forest. The area shown is about 10.3 km east-west by 11.2 km north-south.

More information can be found on the Significant Topographic Changes in the United States website.