The profiles in the upper and lower inmages are from the topographic map DEM and the ASTER DEM, repectively. The profile in the upper image was used for the analysis. The profile in the lowet image serves to show that the breakpoints in the upper image are real and not artifacts of the DEM production process.

Part of the difference between the profiles arises because the alignment of the profiles was not exact, thus part of the difference is real. However, part of the diference arises because of errors in the elevations in the ASTER DEM. These errors are acceptable given that the purpose of the lower profile is to confirm that the breakpoints in the upper profile are not artifacts. The lower profle cannot be used to confirm the location of the breakpoints and their elevations.