Geographic Information Systems (GIS) (Cambridge (CIE) IGCSE Geography): Revision Note

Using GIS

• Geographic Information Systems (GIS) is digital software which analyses and displays data on maps

• Each GIS map is made of layers, each of which shows different information

• The maps can then be used to:

  • Identify correlations and patterns

  • Assist in:

    • Urban planning

    • Disaster management

    • Environmental conservation

• Using GIS software, users can:

  • Zoom in and out to different scales

  • Turn layers of information on and off

  • Add data

• The complexity of GIS maps depends on the purpose of the map

• Google Maps is an example of a GIS application

• Within fieldwork enquiries, GIS can be used either:

  • To display primary data

  • As a source of secondary data

Benefits & Limitations of GIS

Benefits of GIS

• GIS applications are used by businesses and governments

• The use of GIS has several benefits, including:

  • Improved decision-making because they clearly show patterns and relationships between different sets of information

  • Effective planning for example when making decisions about where to place new housing or an industrial estate

  • Market analysis to make decisions such as where to put a new supermarket

  • Disaster preparedness and response by examining the areas most at risk

Limitations of GIS

• GIS can be expensive

• Inputting the data required can be time consuming

• Quality GIS output depends on quality data being inputted, which includes:

  • The accuracy of data

  • Whether the data is up to date

  • Consistency between types of data

• Bias when using GIS is also an issue because:

  • Many maps still use the Mercator projection, which distorts the size of countries and regions

  • The information shown depends on what is selected by the user