WHAT IS GIS


Outline

  1. Definitions
  2. Implications to Geography
  3. GIS as Interactive Cartography
  4. GIS as Nothing New


Definitions

GIS as a Toolbox

A GIS can be seen as a set of tools that allows the user to analyze spatial data, such as maps. Like a toolbox that holds a set of tools that enable the user to create or repair an object, GIS is software that contains within it the elements necessary to work with almost any type of spatial data. If a GIS is like a toolbox, then one may ask what types of tools are contained within it? One definition that may explain this is that a GIS is "an automated system for the capture, storage, retrieval, analysis, and display of spatial data." (Clarke 1995, 13). One example of this would be the software's capability of overlaying one map on top of another map and using subtraction to find the differences. Take, for instance, a forestry business is looking for ways to improve growth of the trees by finding areas where growth can be enhanced. The company would look at drainage and soils and use analysis to find ways to improve the forest growth. A second definition is that GIS is like an inventory. The same forestry service would use the inventory system to keep track of land use. It's simply record keeping.

GIS as an Information System

When stating that a GIS (as the name implies), is an information system, it implies that, "a GIS collects data, sifts and sorts them, and selects and rebuilds them to find the right information to answer a question." (Clarke 1997, 3). This definition includes the user as part of the system. The user will pose the question for the software to figure out, or some type of analysis for the software to perform (this is usually a broader type of question, using several different queries for the software to solve). This idea for GIS was derived from Management Information Systems. It is based on an inventory notion, i.e., that the primary purpose of the system is to build an inventory of spatial information that can later be queried.

GIS as an Approach to Science

The discipline of geography has had a long history of trying to promote itself as a "real" or "hard" science. Academics are looking at GIS as a way to achieve this goal. Instead of GISystems they want GISci. The inventory approach would be useless to science; however, the analysis part of the toolbox should have something built on top of the toolbox for the tools to be used in a scientific way. The invention of GIS has changed geography into a whole approach to spatial data analysis. The use of GIS with other technologies such as remote sensing and computer science has helped in the restructuring of the perception of geography. It has also helped geography cross over into other fields such as anthropology, epidemiology, forestry, and business. All of this together, has led geography to resemble these fields as a "new approach to science" (Clarke 1997, 5).

GIS as a Multibillion Dollar Business

GIS software, that was usable on the newly designed personal computer, began back in the late 1980s. Now almost twenty years later, the industry has become a $6 billion a year business. A large contributor to this rise in the industry is the huge cost reduction in computers, making them available to a wide variety of people and not just to scientists. At first it was only the federal government that used GIS because of the high price and type of computers available at the time. Later it would move into the state government, the local government which is still very strong today, and finally into the businesses. Other major driving forces behind the growth of GIS are urban applications and environmental controls. Almost every local, state, and federal agency uses GIS software to track infrastructure, to help facilitate growth and to track environmental hazards, such as pollution.

Implications to Geography

Applied Geography

With the creation of GIS, geography has gained the ability to apply geographic ideas, principles and concepts to real world problems. This implies that the old perception of geography was that, the discipline itself was not a useful one. Most of geography was unable to apply itself. Then the applied geography movement set in with GIS changing this negative view of geography. Now there was a software package that enabled geographers to show the capabilities that the discipline offered.

The Revitalization of Geography

As stated above, GIS changed the perception of geography, which led to the revitalization of the discipline as a whole. One of the most important things that led to the revitalization of geography was in the late 80s and early 90s, reports were written about students at colleges, who knew little to no geography. For example, 25% of freshmen polled at the University of Miami couldn't find the United States on a world map. Adding technology to geography raised the standards. It can now be seen as a cutting edge field, with real information that can be verified. As early as 1974, this revitalization due to GIS can be seen in the amount of software created. The International Geographic Union, found that there was so much GIS software out there that they could publish an entire volume of information called, The Complete Geographic Information Systems.

Job in GIS

 As geography became revitalized through the creation of GIS, the employment possibilities skyrocketed. These jobs usually demand a Geography degree as well as specific knowledge and 3 or 4 years experience. This was not a possibility twenty years ago. More often than not, the demand calls for a higher level degree earned, such as an MA, to ensure that the applicant is able to think and write as well as manipulate the software. Most of the jobs are fairly high paying, at approximately $50,000 +.

GIS as Interactive Cartography

Static vs. Interactive Maps

What we have been discussing is what GIS really is. In plain terms it can be seen as another form of cartography. In cartography, the maps are static, meaning one cannot really interact with them. Also with the static map, you have the problem with described in the "basic law of map use" that states that the area of interest is always at the intersection of four maps. GIS, however, has the ability to create an interactive map where the user can manipulate the software, enabling the screen to change the display and analyze the data that has been mapped. Once the map is created, you are able to add something else to produce another map, and then another and so on. The interactive maps can be centered on any location.

The Analysis Distinction

The ability to analyze the data is what distinguishes a GIS from regular cartography. Most maps are pictures of some aspect of the real world. Through software tools, the GIS can analyze the data that is being used, in order to answer questions pertinent to that particular place mapped. The goals of the two separate sub-disciplines are different, where as the cartographer's goal is to create a map, a GIS analyst's goal is to also make a map but to go on further and perform some type of query or analysis with the map created. But, this is a simplistic distinction - see below.

The Usage of GIS for Mapping

Although GIS performs the function of map making, it can also create tables, graphs, other databases and reports, which in turn, are mostly used to create another map, in part due to the map being easiest form of information display for the majority of people to analyze. In actuality a GIS enables the user to establish a relationship between data and the computer, which alone the user is unable to do.

Maps also used for Analysis

One major point to stress here is, that although GIS enables a user to more simply analyze data and the cartographer's map is not interactive, all maps can be used in some way for the purpose of analysis. Have we not used maps for measurement and comparisons for years? So the earlier distinction between GIS and cartography is not one of just analysis abilities. According to Kurt Brassel, "we understand that a mapping system is mainly designed for display purposes, even though it may fulfill some secondary functions that are not graphical. A geographical information system is designed for a broader range of applications, even though mapping functions may represent an important subset of its activities" (Brassel 1977, 71 in Clarke 1997, 9).

Cultural View of New and Old

There are many different cultural views to consider when dealing with a new technology such as GIS. Many Europeans believe that people have been doing GIS for hundreds upon hundreds of years. An example would be Dr. Snow and the cholera epidemic in London. He mapped out where all the cases of cholera were located and found the reason was the water in the wells. It's nothing new; it's a progression in the way we make maps. Some Europeans also believe the Americans are only recreating the wheel over and over again. They are much more skeptical of things that are supposedly new.

GIS as Nothing New

Progression of Cartography + Computer

GIS could be viewed as a simple progression of combining maps with computers. It is simply cartography with the added benefit of using a computer instead of manually drawing and analyzing maps.

Integration of Related Technologies

GIS has created an integration of technologies from several areas. Remote sensing, Cartography, Photogrammetry and Computer Science are just a few of the areas that are used in GIS and integrated into the field of geography. Any one of these areas was not able to integrate all of these functions.

Creating a Larger Umbrella for Cartography

All of the information given above together creates a larger umbrella for cartography that forces it to create connections with the outside, to solve real world problems. No one can foretell the future and we do not know how long GIS will last. According to Clarke, "While GIS's lineage goes back to the roots of cartography, and although thematic cartography and map overlay date from the nineteenth century, what is today known as GIS owes its birth to a cluster of interrelated events and human interactions in the 1960's, and its spectacular growth to the microcomputer, the workstation, and the internet." (Clarke 1997, 10). GIS with all of its benefits will most likely be here to stay and the biggest influence will be the World Wide Web.

What does the future hold?

Many believe that in the future, as computer speeds get faster, we won't need the software for GIS on our own computers, rather the software will be on a distant computer. We would only have to access the server on the web.


Submitted by Lauren Shapiro on 16 Jan 1988. Updated by Jody Parker on 23 Sep 2000.