Accuracy of SPOT digital elevation model and derivatives: utility for Alaska's north slope

This investigation not only evaluates the accuracy of a portion of a SPOT DEM but evaluates products derived from it; namely, slopes, aspects, and thickness of thaw layer. A DEM was created from an image pair with less than optimum difference between image acquisition angles at a study site in northern Alaska. Root mean square (RMS) errors for elevations were 19.3m and 13.7m and for slopes were 2.7% to 4.0%. Aspects agree in general slope orientation. Even though the area had relatively low relief (~250m with a ~25km² area), the SPOT-derived DEM provides sufficiently accurate ground elevation, slope gradient, and aspect data for use in ecosystem investigations. -from Authors