Observations At Altitude

I recently took our new GPS unit for a drive with me to town. As I have mentioned before, we live halfway up the far side of a valley just north of Fairbanks. When we first moved here, I noticed that there were very few houses on the south side of the valley, but once you pass over Goldstream Creek at the valley floor, there are quite a few roads leading off to little cabin enclaves like our own. Now that the sun is making her daily rounds decidedly in the south, I understand why. By solstice, I don't think the north side of the hill will be getting any direct sunlight at all. (If you watch the Winter Solstice Video on the links bar, you will notice that much of Fairbanks remains in shadow, even though the sun is technically in the sky.)

In order to get to town, we drive down to the bottom of our valley, up over a hill, and then down again into the Tanana Valley where Fairbanks lies. I have noticed that the temperature often changes significantly over the course of the drive to town, and have wondered about our cabin's relative elevation at various points along the trip. I took the GPS to get an idea of just where we were when the car thermometer shifted around. These are the readings I took:

Solar Cabin :: 788 ft.
GS Valley Floor :: 716 ft
Crest of Hill :: 960 ft.
Chena River :: 512 ft.
(almost at the) Tanana River :: 430 ft.

(The Chena river is a small, swift river that runs through the middle of town, and empties into the Tanana river - a monster of braided water - that borders Fairbanks to the south and eventually runs into the mighty Yukon.)

Ducks On The Chena

A Braided River (Not the Tanana)

On a typical day (and this is by no means scientific) the car thermometer will read

Solar Cabin :: 25
GS Valley Floor :: 27
Crest of Hill :: 23
Chena River :: 30
Tanana River :: 30

According to local observations of Cold Inversion, where (in conditions of extreme cold and minimal wind) warm air traps cold air in the valleys, the temperatures at our elevation should be higher than those on the valley floor. This is counter to the logic that the higher you go, the colder it gets, and explains why most Fairbanksians - at least, those who can afford it - live on the hillside north of town (They get the sunlight the city misses around the middle of December, as well a several degree warmth advantage to bolster their heating bills.) In the newspaper, many houses are advertised as being "above the fog." This translates to above the temperature inversion line which causes the ice fog that I referenced last month. It can be as much as ten to fifteen degrees warmer on the hills.

So far, our temperatures are always several degrees below those in town. This is, of course, in keeping with the idea that a lower elevation (around 400 feet) will be warmer than a higher (800, here.) It remains to be seen if our little cabin is high enough to enjoy some warmer air when the mercury really drops, or if the Cold Inversion we hear so much about is a phenomenon which effects only the Tanana Valley - a much larger geological feature, with a much greater elevation difference. Although ultimately, I don't know if a difference between -30 and -15 will really be that noticeable in the outhouse.