Isoline maps
Isoline maps show lines that join up areas or values that are equal. In this example, air pressure is shown using the isolines. The areas of equal pressure are joined using a line, which helps people to see the position of high and low pressure systems. Generally, when the number is below 1000 we would consider that low pressure, and when over 100 it would be high pressure.
Question
Compare the air pressure between Scotland and France.
Scotland is experiencing low pressure whereas France has high pressure.
For example, the isolines in Scotland are between 972 and 992 whereas France is between 1016 and 1028.