1.3. Scope of GIS

         When GIS was first developed, the only area of application was land and resource information management. Today GIS is used in all sectors of the economy and for applications pertaining to both Earth’s natural environment and human activities. As the areas of GIS application have become more diversified, the scope of GIS has also undergone significant changes over the years.

The scope of GIS can be summarised as five ‘M’ s. They are

◦         Mapping

◦         Measurement

◦         Monitoring

◦         Management and

◦         Modelling

 

Mapping

GIS enables us to map the spatial location of real-world features and visualize the spatial relationships among them. As a tool it assists in

◦         Mapping quantities - such as where the most and least are found to make a comparison possible between places.

◦         Mapping densities – To find out the concentrations.

◦         Finding what is inside - what features are located inside a specific area/region.

◦         Finding what is nearby - We can find out what is happening within a set distance of a feature or event by mapping.

◦         Mapping change - We can map the change in a specific geographic area to anticipate future conditions, or to evaluate the results of an action or policy.

Measurement

GIS help us to measure distances, areas, feature locations as well as altitude from a map.

◦         Measurement of distance may belong to one of the following types

◦         Planar measurement using two-dimensional cartesian coordinates to calculate lengths and areas.

◦         Geodesic measurement to find shortest line between any two points on the earth's surface on a spheroid (ellipsoid).

◦         Loxodrome which defines the line of constant bearing, or azimuth.

 

Monitoring

GIS provide an effective and ideal environment to perform monitoring and change detection. Monitoring may be related to

◦         The location of a feature or phenomena over time

◦         The change of shape of feature or spread of phenomena over time and

◦         The change of size of feature or extent of phenomena over time

◦         The change in quality of a feature or phenomena over time

 

Management

GIS can be used effectively for the following.

◦         For the management of spatial data.

◦         For the management of natural resources.

◦         For the management of hazards and disasters and

◦         For facility management.

Modelling

Models are used in a vast array of GIS applications. A model is an abstract of reality. Reality is so complex that it is impossible to reproduce all its functional relationships. GIS is an effective tool to model the reality and to represent the complex relationships therein. Globe is an example of a model of the Earth.


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