A National Topographic Change Mapping and Monitoring System

The three-dimensional (3D) form of the Earth’s surface results from both abiotic and biotic forces. Major abiotic forces, such as tectonic uplift, erosion, and climate, exert strong influence over land surface morphology. Biotic forces, including, significantly, humans, also shape the landscape, but often at different temporal and spatial scales and magnitudes than geologic forces. Because the processes shaping the land surface, as expressed in its topography, are ongoing, topographic change is ever present and is a factor that must be broadly considered in studies of natural and built environments. Remote sensing data, especially in the form of derived high-resolution measurements of the topography, have been widely used to assess [...]