National Center for Geographic Information and Analysis

Although the vast majority of GISs currently work in only two dimensions, across the plane, certain applications require the addition of other dimensions. This unit examines how time and the vertical dimension—i.e., elevation or depth—can be incorporated into GISs. It describes methods for representing phenomena in “2 ½ dimensions” as well as a full three dimensions and provides examples of when each might be applicable. The unit concludes with a discussion and examples of time dependence and representation in GIS.