About the
Topography and Surface Change Program

The past decade has seen increasing awareness of the Earth as a system, and an appreciation of the interacting relationships among the geosphere, hydrosphere, biosphere and atmosphere. Shaped by both internal and external forces, the Earth's surface is the boundary where interactions among these systems occur. The record of these interactions is in the Earth's crust and land surface topography and is the only long-term documentation available for study. Understanding the processes that shape the Earth's surface is therefore important to many aspects of Earth science, and knowledge of topography and its changes through time is fundamental to this understanding.

In pursuit of this understanding, NASA has developed the Topography and Surface Change Program for the acquisition and scientific utilization of digital topographic data for studies of the land surface and its changes.