Residual misregistration causing false detection of vertical change

Example of residual misregistration causing false detection of vertical change. From left to right, the images are NED shaded relief, SRTM shaded relief, SRTM NED difference grid (blue = significant decrease in elevation; red = significant increase in elevation), and areas of significant differences (outlined in yellow) overlaid on SRTM shaded relief. There are no actual topographic changes in this area in south central New Mexico. Note that the areas of significant differences are located immediately adjacent to sharp changes in the topography (ridges and cliffs). The area shown is about 3.9 km east-west by 10 km north-south.

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