August 31, 2008 Impirical evidence gathered by countless millions of people chained to a desk indoors during weekdays would suggest that the weather on the weekends is different to that during the week. As much as it might seem like a nonsense that the weather could possibly fall into a cycle based on an arbitrary human measurement of time, Spanish researchers have found evidence that in some parts of Europe the weather really does follow a weekly cycle. Evidence has been mounting over the years that the weather in certain parts of the world, including the US, Japan and China, can be driven by the weekly cycle of human activity. This is because we tend to produce more air pollution during the week and less at the weekend. Evidence that such an effect occurs in Europe is controversial and has been harder to come by.