Geography Reference
In-Depth Information
of speed, accuracy, and data management that were unimaginable a few years ago. These qualities
have also served to make mapmaking a powerful tool for a variety of businesses and planners. And in
that regard, the most significant, cutting-edge field in contemporary cartography is the
geographical
information system (GIS).
Giving you the complete lowdown on GIS would involve a lot of techo-babble that you don't want to
read and I don't want to write. So perhaps the best way for me to describe GIS begins with a descrip-
tion of what it has replaced.
If you had poked around a city or regional planning office 20 years ago, you'd be sure to find a huge
table someplace with a huge base map that showed the streets and roads of the city or region in ques-
tion. There would also be numerous overlays of different phenomena drafted on individual pieces of
transparent film. For example, one transparent overlay might show the location of property boundar-
ies. Others might show land use, sewage pipes, water mains, building characteristics, telephone lines,
school districts, voting precincts, contour lines, wooded areas, and anything else that may be deemed
useful for planning purposes.
Again, each characteristic would be on its own piece of transparent film — that is, its own map. So
if a planner wanted to see how two phenomena coincided geographically, the respective transparent
films would be manually overlain on the base map and comparisons manually noted. Of course, the
landscape changes. Thus, every so often a particular overlay would have to be manually updated or
manually redrafted from scratch. If all of this sounds a bit tedious, then you get the point.
With the advent of GIS, all of those physical base maps and pieces of transparent film have been re-
placed by layers of information that exist in computer memory. This permits multiple layers, or even
parts of layers, to be compared electronically, which is to say instantaneously. But the bottom line is
that GIS has given geographers and planners the power to map and compare phenomena with great
speed and accuracy. Indeed, remotely-sensed images can be directly “fed into” a GIS, reducing to
minutes and seconds a process of field observation and mapping that used to take weeks and months.
Does this electronic gadgetry mean that the romance and adventure of maps are gone? Not necessar-
ily. Nearly everyday I see students gawking at maps, just as I did. True, the maps they are staring at
are on a computer screen instead of the pages of a topic, and are more likely to be products of remote
sensing instead of expedition. But the intense fascination on peoples' faces is palpable, so the old
magic must still be there — the same old symbols certainly are — gray tones, different colors, tiny
airplanes, and crosses. Some things don't seem to change.
