Computer Analysis of Topography: A Comparison of Terrain Storage Methods

Abstract

Topographic information can be digitized in several ways. Sampling may be surface-random or surface-specific. Surface-random sampling includes grids, contours, and randomly-located points. In this study, grids and surface-specific sampling are compared with reference to the problem of estimating certain geomorphometric parameters. Results of empirical comparison of the methods over six selected topographic samples are presented. The assumption of a linear relationship between grid spacing and grid error is used to estimate the grid spacing which would be required to produce the same average errors as the surface-specific point samples. For the three parameters used, these hypothetical grids require more digitization time and computer storage space than the surface-specific point data sets.