How do you visualise climate change simply and evocatively? Well, you could knit it.

I’m quite fond of knitting as a method of visualising complex information (like non-Euclidean geometry). Back in 2017 a whole bunch of data about the current climate crisis was going to be purged from US government websites – out of sight, out of mind, I guess. So a trio of knitters decided to do something about it.
The result was the Tempestry Project. Imagine a location’s climate data encoded as coloured stripes in a blanket, scarf, or banner. Each row represents the average temperature for a single day. As the average temperature increases, the colour of the knitting transitions from a cool green or blue into a fierce yellow, orange, or red. It’s a pure visual: no labels, notes, scales, or explanations. Just the irrefutable march of a warming planet.

Related to the Tempestry Project (which, by the way, is a “temperature tapestry”) are warming stripes. These stripes convey the same kind data as Tempestry fabrics, except they typically show changes over years rather than days. Consider this visualisation of global temperature changes from 1850 to 2018:
