Known as Geographical Information Systems, or G.I.S., the technologies link traditional mapping techniques with vast data bases and are being widely used in a range of activities as varied as urban planning and epidemiology. Geographers who had grown used to feeling marginalized have suddenly found themselves playing key roles in many research projects around the world. A G.I.S. display usually consists of a standard map of a given area. It can be linked to any number of data bases, such as those showing population density, soil usage, automobile ownership, incidence of disease, or ownership of specific plots of land. These disparate data bases can be displayed individually or together, with the data illustrated on the map by various means, such as colors.
Researchers can use such displays to spot trends instantly.
For example, someone looking for evidence that the use of cellular telephones increases the risk of developing a brain tumor might want to compare a data base showing the incidence of such cancers in a given area with a data base of cellular-phone ownership in the same area. G.I.S. can display both data bases on a map simultaneously, allowing a researcher to look for places where there is significant overlap. Sought Out By Colleagues Academics have been using G.I.S. for well over a decade, but until about 1990 the best software was available only for sophisticated workstations, far too expensive to be widely available. Over the past few years, however, advances in the power of common desktop computers, combined with efforts by software developers to recast their products to run on those machines, have made G.I.S. commonplace. Now geographers are sought out by colleagues in other fields who want help with their research.