The Nordic Warming Stripes provide a visual representation of temperature change in Denmark and Greenland, based on the original climate stripes of Ed Hawkins at the University of Reading. See Ed’s original stripes and other climate visualisations over at his website, the Climate Lab Book.
Here are my attempts, which go up to 2017:
The Concept
The intention of Ed’s design is not to provide a scientific presentation of temperature data per se, since that is best achieved as a simple line graph. The stripes are instead a way of communicating the undeniable trend in global and local temperatures observed since records began. This is achieved by simply showing temperature change represented by colour.
The result is invariably a depiction of shifting colours from blues (cooler temperatures) earlier in the record to pinks and reds (warmer temperatures) as you move along the stripes, towards the present day.
How it was Done
I imagine that Ed created his stripes in Matlab. But given my almost non-existent programming skills and complete lack of access to Matlab, I set out to find a low-tech method of reproducing a set of stripes for the Nordic countries.
So, my stripes were created in Excel. But I did need some programming help as it required a set of macros written by my wonderful programmer dad, Colin Jex.
After copying a temperature series into a worksheet, the macros essentially do 3 things:
- Assign a colour fill to each cell in the data series, according to a colour scale and step value set elsewhere in the worksheet.
- Produce a bar chart, which simply plots a value of ‘1’ for a given date range within the same worksheet.
- Assign each bar in the chart a colour, according to the scale set in step 1.
Credit: Catherine Jex