Looking at the calendar this morning I had a thought on how seasons are defined.
The Solar calendar, as embedded into our counting of the years, and according to the paper calendar I was looking at, defines seasons in terms of solstices and equinoxes. According to the printed calendar, winter doesn’t start until December 22nd this year. By my reckoning, that means that the seasons are as follows (for 2008):
- Winter: January, February, March (Dec 22-Mar 20)
- Spring: April, May, June (Mar 21-Jun 20)
- Summer: July, August, September (Jun 21-Sep 22)
- Autumn: October, November, December (Sep 23-Dec 22)
That feels really odd to me. Thinking about it, it’s because I’m heavily influenced by the Academic calendar, which follows more the ancient roman calendar, and defines seasons in whole months. For (2007 going into) 2008, that would be:
- Winter: December, January, February
- Spring: March, April, May
- Summer: June, July, August
- Autumn: September, October, November
Which is almost a whole month (ok, 3 weeks) off from the solar calendar. Not actually a lot of time, but it feels like a big difference. So,
How do you define your seasonal calendar?
Addendum: Peeking at Wikipedia, I am reminded that these seasons refer to the temperate zone. Tropical seasons and polar seasons are obviously greatly different. I’m also reminded that these are seasons for dividing the year, and not seasons in the sense of hurricane season, blizzard season, or baseball season. Lastly, Wikipedia points out another yearly temperate cycle division called the Traditional Seasons, which set their seasonal *midpoints* at the equinoxes and solstices, so they start a whole month before the Roman, and 7 weeks before the Solar/Astronomical calendars. This reckoning was apparently embraced by different cultures, but some of you would recognize the Traditional seasonal boundaries as Samhain (early Nov), Imbolc (early Feb), Beltane (early May), and Lughnasadh (early Aug). This seems to be the classic agrarian calendar, with seasons of planting, growing, harvesting, and fallowing. In contrast, the Roman calendar seems equated with a meteorological calendar, i.e., linked to max and min temperatures, not max and min sunlight hours. See also The Straight Dope.
