Weekend effect: Anthropogenic or natural?

Abstract

Human activities have been suggested to result in weekly changes of meteorological variables, called the “weekend effect.” Recent debates on its statistical significance, however, reveal that there still remain huge uncertainties as to the anthropogenic origin of the weekend effect. We show that atmospheric Rossby waves induce the “natural” weekend effect, which is much stronger than the “anthropogenic” weekend effect. The “natural” weekend effect does not completely disappear even with averaging over 61 years of data; as a result, true “anthropogenic” weekend effect is obscured by the natural component. We attempted to remove the “natural” component in the diurnal temperature range and the resulting pattern is an overall positive weekend effect over North America.