An Introduction to GIS

Maps have been used for thousands of years to present and analyse geographic information. Geographic Information Systems, or GIS, are the most recent incarnation of this process, a dynamic and continuously developing field of technology. GIS is a powerful tool - the technology can be moulded to the needs of many and can be used in numerous areas of work, from simple map production to complex spatial analysis.

However, a GIS does more than simply retrieve existing information. In addition to storing and producing map data, a GIS can be used to manipulate and analyse the geographic information since it is stored as a model of the real world rather than as a static map. GIS can produce new information by combining existing information in new ways. This value-added information can be used to help better decision making.

As an example, during the winter months GIS can be used to co-ordinate the gritting of roads. Data can be obtained on the road system, the location of all the gritting lorries, the amount of grit needed for the size of road, and any other data that may be appropriate. This data can then be integrated to provide a strategy to grit as many of the major roads as possible in the shortest space of time. We can analyse which roads should be gritted first and which lorries can do which roads – this can be passed on to the drivers along with information about the roads they are gritting. This means not simply providing a route to follow, but actual information about what type of road it is and how busy it is likely to be.

Another example of the power of GIS to produce new information to enable better decision making is the process involved in finding a location for a new waste incinerator. Using GIS you can do more than simply produce a map of potential sites. GIS enables you to input data of the various requirements involved in the decision making process; the GIS can then integrate these datasets to give a decision free from any personal bias. The GIS can also be used to produce data about the spread of any potential pollution from the incinerator. Information such as weather data and expected output levels from the incinerator could be integrated and a plume dispersal map could be produced to show areas at higher risk from pollution.

ArcMap, Webmaps and Webmaps-extra all contain powerful sets of GIS tools - they are not a GIS solution. GIS solutions do exist, e.g. AutoRoute, but they are designed purely for one purpose and cannot be adapted for other uses. Instead, the GIS packages used at HCC can be used to serve an infinite range of requirements and can be moulded for the needs of any User. However, as with any set of tools the quality that you get out depends upon the skill and experience of the User - the quality of the output depends upon the quality of the input.