One side effect of having the photography habit is that you are your own phenologist (phenology: "The study of cyclic and seasonal natural phenomena, esp. in relation to climate and plant and animal life"). It helps, of course, if you keep your files in some sort of chronological order, which I do.
As I think I've said before, the end of the year is a genuine marker in the cycle of life on our planet, especially if you live away from the tropics, and experience well-defined seasons. In the North, the shortening of the days until the Solstice on 21st December and then their gradual lengthening is a fact, not an opinion or a construct. Saints days and such are comparatively random, but tend to coincide suspiciously well with seasonal markers -- the rhythm of the year (especially the farming and hunting year) is too insistent to ignore. Although it can be pretty faint, heard deep in the air-conditioned, air-freighted depths of a supermarket, like the bass in a car stereo two streets away.
The variations are fascinating. In 2010 we had snow and deep frost:
In 2011 it was bright and clear, with no ice on the ponds:
This year, after a cold start, it looks like we're headed for another bright, mild year's end:
Though rumours of large numbers of waxwings and redwings on the East Coast might suggest otherwise. In 2010 we had redwings in the copse behind our house, frantically tossing fallen leaves about, as if they'd dropped their car keys. The most notable anomaly so far has been the behaviour of the goldcrests. These beautiful, tiny birds have been coming right up to the house, foraging in the creepers on our shed, giving me an eyeball to eyeball view through the back-door window. Normally, they skulk about at the far end of the garden. Something has changed, or is about to change, but what?