California Mountains - The Snow Crystal Tour 2002-03
In another installment of our Snow Crystal Tour, my
family and I set out in December 2002 to drive around the Sierra-Nevada mountains for a
couple weeks -- to ski, photograph snowflakes, and generally see the winter sights. In the hopes of getting so good snowflake pictures, I modified the SnowMaster (see Photographing Snowflakes) so it could be powered with 12 volts DC. It conveniently just fit in the back of our small SUV, so we were all set for some mobile snowflake hunting.
Yosemite Valley & Badger PassYosemite is as beautiful in winter as everyone says it is, and the valley had seen a lot of snow just a few days before we arrived.
Down in Yosemite valley, at 4000 feet elevation, it was too warm to see good
crystals. Even at night the snow was wet and gloppy. Nearby Badger Pass, at
7000 feet elevation, provided some good crystals, although most were covered with rime.
Blue Snow?
At Badger Pass I poked some holes in a snowbank with an icicle and found the holes were blue-green in color. Why the color? It's because ice absorbs red light more strongly than blue light, so inside the snowbank the light tends to have bluish tint. The absorption minimum in ice is actually around 470 nm, which is blue-green. The effect isn't always so vivid, however; I tried this same trick on some some other days, with other snowbanks, and usually didn't get such good color.
Tamarack, CA, is known for snowfall extremes. In January of 1911 it experienced the most snowfall ever recorded in a single month in the U.S. -- a respectable 390 inches. In the 1906-7 season, Tamarack was hit with a total of 884 inches of snow. We arrived just a few days after a major storm, but already the locals were pretty well dug out. Still, there was a lot of snow around.
We found some excellent frost formations on the front door of this lodge one morning. The crystals shown here are only about 2mm long.
Tahoe and Cougar PassSkiing is especially fun in California because there is a lot of snow and it's never very cold. Warm-weather snowflakes are not usually so attractive, however. These were taken at Cougar Pass near Tahoe, at about 8500 feet elevation. Lots of rime again.
The far image shows two shots of a "double star" crystal - two crystals joined in the middle. The two pictures each have a different focus, showing that this crystal is not a simple flat plate.
Sequoia National ParkOur last stop was at Sequoia, where it was again too warm for good snowflakes. But one morning, when my wife dragged me out of bed at first light for a bit of cross-country skiing, we found some huge hoarfrost crystals near a flowing stream. The second picture shows my wife's gloved hand holding a chunk of snow she scooped up from the snowbank. Some of the surface hoar crystals (see Frost Crystals) were over 2cm (a bit less than an inch) long, which is pretty big for overnight growth. The next picture shows a bunch of crystals growing on a small twig.