Summary How to calculate real distance and areas from a map

How to calculate real distances
and real areas from a map




Department of Geography
GGH1501


Compiled by Mnr C Hamann

,Important notes about measurements
and the use of map scales
• The accuracy of your measurements has
important implications for small scale maps
• Consider the following: What does it mean
if your map measurement is wrong by 2
mm…
– On a 1:1 000 scale (your real distance will be
wrong by 1 m)
– On a 1:500 000 scale (your real distance will be
wrong by 1000 m!!!)

, Important notes about measurements
and the use of map scales
• Remember that a map scale represents the
relationship between the distance on the map and
the real distance on the ground.
• This relationship does NOT depend on your
measuring tool. Consider a 1:10 000 scale map:
– 1 mm on the map equals 10 000 mm in reality
– 1 cm on the map equals 10 000 cm in reality
– 1 length of your cell phone on the map equals 10 000
lengths of your cell phone in reality
– THE RELATIONSHIP REMAINS THE SAME.