seasonal cycle

The seasonal cycle is the same as the mean annual cycle, the typical variation over the changing seasons, from January 1st to December 31st. It is estimated for the 12 Calendar months January-December, by taking the mean of all January months, the mean of all February months, and so on. The mean annual cycle is often also referred to as the ‘climatology’. It is a useful aspect of climate since it is caused by well-known variations in the climate forcings, such as variations in the solar inclination.