Edinburgh Wind Rose

Illustrating how airport runways are aligned to prevailing wind directions. This is Edinburgh Airport, showing the last year's worth of wind directions as a wind rose. As in most of the UK, the wind tends to come from the SW or NE.

 

All the rendering was done in QGIS Composer, no other graphics packages or libraries were used.

 

Inspired by this map by Andy Tice.

 

The wind rose is created using a Python script. The maths behind this is just simple trigonometry, and would be easy enough to do in Excel / LibreOffice or similar.

 

This script takes historic weather data in CSV format from Weather Underground, and creates a modified CSV file. That is then loaded into QGIS as a delimited text file POINT layer, which is then styled up as arrow symbols. The star marks the centre of the rose, the arrows show the bearing, and the distance out (and size) represent wind speed.

 

The heatmap was done in QGIS by loading the same CSV and setting the x coordinate to the row number (representing successive dates) and the y value to the wind bearing. The weight was set to the wind speed value.

 

Weather data downloaded in CSV from Weather Underground. Map data copyrght OpenStreetmap and its contributors.

 

Weather Underground bearings are relative to true north, rather than magnetic north (otherwise the angles would be out 1.5 degrees). I've assumed here that grid north here equals true north (not technically correct, but close enough)

 

QGIS Features used :-

 

- multiple maps in composer

- frames

- custom grids with differing x/y intervals and labelling inside frame

- semi-transapent text and map panels (can change opacity of background with color picker in 2.6)

- heatmap

Done