Figure Box 2-2: Westerly component of the wind across New Zealand

Text description of figure

Schematic shows how mean wind is made up of daily winds with different direction and speed. The solid arrows represent individual wind speed and direction values. Dashed horizontal lines are the westerly components of these winds - positive when they point to the right and negative when they point to the left. The mean westerly wind component is simply the average of the individual westerly components: in the schematic shown these are a westerly of 3 m/s, an easterly of 2 m/s and a westerly of 2 m/s which averages out to a westerly wind component of 1 m/s.