An autographic visualisation, documenting sunlight and precipitation.
I placed a piece of paper coated in cyanotype chemicals outside my home for ten minutes at the same time every day for a week. Cyanotype chemicals turn blue when exposed to UV light, and get darker the longer they are left out for. The process is stopped when the chemicals are exposed to water.
The darker blues show brighter days, and rainy days are easy to spot because the individual raindops are visible. Viewing multiple days side-by-side allows patterns to emerge, building up a picture of the weather over the time period.
Further research and information about my process can be found here.