London has a reputation for being perpetually gloomy. And yet, although the frequency of sunniness in London is in fact subpar, there do exist major cities on Earth that naturally experience even less sunshine than London.
The below chart plots the frequency of sunniness in June and in December in several locations across the world. Note that sunniness requires (1) that it is daytime and (2) that there aren’t obstructing clouds. For instance, during an equinox, it’s day approximately 50% of the time, so with no clouds ever sunshine frequency during the equinox is 50%.
Note that associated with each location is a line connecting the plotted point to a corresponding point on a central diagonal line. That corresponding point represents what frequencies would be in a city of that latitude if it was sunny 50% of the daytime, for further comparative purposes.
This chart is made with Raphael.js.
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