maps. Computer technology5 would allow them to store, process, analyze, and display spatially distributed data in various forms, including but not limited to maps. This use of computer technology came to be called geographic information systems (GIS).

What eventually linked these two rather disparate endeavors of automated cartography and GIS was the shared need for digital data to “fuel” the machines used to capture, store, manipulate, analyze, process, and output data as information for a given user or user community. It was fortuitous that at the time this need for digital data products was increasing, the technology of remote sensing was beginning to produce large quantities of digital data that could be employed in the cartographic process and GIS. This synergism between automated cartography, GIS, and remote sensing has had a significant impact in accelerating the pace of technological innovation and expanding the market for GIS systems. Researchers have found that map-derived digital data in a GIS can improve the accuracy of interpretation of remotely sensed data while remotely sensed data provides the ability to update map products in a more expeditious manner. The data produced by all these systems have a spatially referenced component (“earth location-referenced” might be a more accurate term). For consistency such data will be referred to throughout this report as spatially referenced digital data (srdd). This is not to say that srdd sets appropriate for creating a map are always necessarily identical to those used in a GIS; but they do share, at a minimum, coordinates that allow some “interoperability” where shared locations, expressed digitally, act as a medium for data exchange.

In 1989 the distinction between the two original endeavors, automated cartography and GIS, has become blurred. The argument could be made that any distinction is no longer accurate or even appropriate and might, indeed, be creating troublesome “pseudo-issues.” It would be easy to dismiss this matter as mere word play, but the fact is that a rigorous, useful analysis of NMD’s role in an era of technological transformation and transition is impossible unless some agreement is achieved concerning the nature of NMD’s current and future role in what was formerly the “cartographic enterprise.” To do this we must continue to compare and contrast GIS with automated or digital cartography.

Geographic Information Systems: Background

Prior to the diffusion of computer technology into so many fields of human endeavor, discrete disciplines evolved around distinct categories of problems and tools to deal with them. Geography, cartography, geology, and related fields shared a fundamental interest in the arrangement of objects, features, and phenomena on the earth’s surface, and in the use of maps for representation (Figure 1). Many of these fields, however, can now be regarded as subsets of the superordinate field of spatial information processing. Specialty tools like the



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