The earth is three dimensional. How do we represent this on paper?

Setting the scene

A map is not a ‘life-like’ representation of the area which it is describing. This seems obvious, however there are some important factors that go along with this.

  1. Scale – The mathematical relationship between the size of the map and the size of the section of earth it is describing.
  2. Generalisation – Process of making decisions as to which features are and are not included on a map.

Scale

A statement of scale is the ratio between the map and section of earth it is describing.

For example,1:100 000 means every unit on this map will represent 100 000 units on the face of the earth. If the unit of measurement was centimetres, 1 cm will represent 100 000 cms.

Generalisation

Variables, such as the size of the area being mapped, are decided by the purpose of the map and how cluttered it will become. There are times when regardless of scale, a specific feature needs to be included for the purpose of the map.

When a large area of land needs to be mapped not all features can be shown. Generalisations are when specific features are chosen to be shown on a map and others are not. For instance instead of drawing many trees, one tree may be drawn to represent a forest.

Activity

Using the Canberra satellite image provided answer the following questions:

  1. What is the scale of this map?
  2. Describe what the scale is telling us about this map?
  3. Using the scale of the map find the distance between the following locations in our national capital area:
    1. Parliament House – National Capital Exhibition
    2. Parliament House – Old Parliament House
    3. Parliament House – Australian War Memorial
  4. Choose a point on Lake Burley Griffin and measure how wide the Lake is. Find the widest point of Lake Burley Griffin and measure it.

Outcomes

Factsheet download: