My suspicions were confirmed by the radio, this morning: it is unusually cold here, this month. According to the weather service, this has been the coldest month since 2005 and is the coldest December since 1980.
When I moved to Fairbanks, in 1990, the winters were much colder than they have been for the last decade, but Decembers tended to be in the -20s, with only occasional dips in to the -30sF. This month’s temperatures would have been more common in the January/February part of the year. When I was teaching high school, that was the “cabin fever” time of the year. There were no holidays or vacations to add variety to the schedule, it was too cold to enjoy being outside for too long, and travel was a matter for calculation. In recent years, that feeling has been much reduced. The District re-arranged some in-service day placements, winters grew much warmer, and people became content to stare at their phones, rather than seek active diversions.
The frost curtain on the coop door persistently captures my attention. In particular, the fact that the frost grows in feather shapes, rather than in the traditional dendritic patterns has occupied my thoughts. Could it be that the ice crystals are honoring the chickens responsible for the humidity in the air escaping at the top of the doorway? My best hypothesis is that the uniform direction of the airflow from the top of the doorway favors a linear extension of the crystals over the more radial growth one might otherwise expect.
While I was clearing snow from the driveway, I noticed another demonstration of the effect of the cold weather. A basketball left outdoors is now in a state of partial collapse. This particular ball has a slow leak and was at neutral pressure at the end of the summer. An air volume contracts in the cold.
Because of that, I suspect that, as the air temperature dropped, the internal pressure fell more rapidly than the leak allowed the ball to equilibrate and the ball collapsed inwards due to the vacuum created inside.
This same phenomenon asserts itself in automobile tires. It is important to monitor the air pressure in the tires because underinflated tires can pull free of the rims if the air temperature drops too much. The problem is exacerbated by the fact that the tires become less flexible in the cold. Tires often have a flat spot where they touch the ground and that flat spot persists until the tire warms up enough to become flexible. If the tires are underinflated AND frozen in an asymmetrical shape, the seal between the tire and rim is subject to forces from unusual directions. It is not uncommon for someone to start driving on out-of-round tires and have a tire abruptly go flat.
Yesterday, I saw a few people joining the Forty Below Club. To become a member, you must pose for a picture at the UAF sign at -40F, or colder, while wearing swimwear. There was a young couple in swimwear departing the scene just as I arrived. By the time I was able to take a picture, a more prudently dressed couple had moved into position.
Although membership will be withheld from them, posing in a parka could still make for an impressive picture if they know people who live in a sufficiently warm climate.
This begs the question: Have you posed in your swimwear in front of that sign?
The sign was not in place while I was attending UAF and I developed too much good sense after graduating.