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.
Arturo Sanchez-Lorenzo of the University of Barcelona, Spain, and his colleagues examined data gathered between 1961 and 2004 from weather stations across Spain to see whether such a pattern existed. They claim to have found it in Spain, as well as hints of weekly changes in air circulation more broadly over western Europe.
This weekly pattern changes with the season, however. In winter there is a tendency for more rain during the week than on weekends, while in summer the effect is opposite and less pronounced.
New Scientist magazine’s August 30, 2008 issue has the full story.