isoline maps

• what are the advantages of isoline maps?

  show gradual change and patterns over a large spatial area

  lines join places of equal value along their length

  uses fixed intervals so changes can be easily identified

  can add colour / density shading to make patterns or trends clearer

  can be superimposed on a base map
• what are the disadvantages of isoline maps?

  variations in the location of each isoline are common

  gives a false impression of equal values between the lines

  requires data from a large number of locations