Wednesday, December 07, 2005

Snow pellets, graupel, simple snow crystals...

It's snowing! For the last 10 minutes around our humble abode the snow has been falling. Thanks to the cold days we've had, the street and driveway are NOT melting anything at all. The streets and driveways have a thin, white covering, and the white stuff is blowing from the edges of roofs.

This stuff makes a noise when it hits the windows, so I don't think it's snowflakes. It looks more like pellets. It's handy to have a shelf full of weather / meteorology books that dear husband and I have collected since college days. So, I thumbled through my old Observer's Handbook, c1982, Her Majesty's Stationery Office (college textbook!) and read the description of snow pellets (no mention of graupel). Okay, time for the Peterson's Guide to the Atmosphere. Hmm, no obvious answer here either. Finally I pulled out LaChapelle's Field Guide to Snow Crystals and learned that it could also be simple snow crystals, since it's too cold for the clumpy big fat wet snowflakes of near-freezing temps. I went upstairs for another reason, and realized I could see the snowy stuff up close out my loft office window, which looks right out on various sections of our roof. Definitely pellet-like. Okay, good enough!

That won't matter to anyone unless they're looking forward to starry snowflakes on their coat sleeves and car windows. Fun, though. I love snow, and the scientific arcana about it and about cold places. I really missed the white stuff when we lived in north Florida. If we lived in a more mountainous and cold-winter place I'm pretty sure I'd be a student of winter mountaineering and glaciers, since I never ended up going to Antarctica as a research oceanographer (saline currents off ice shelves, oooh cool).

This stuff is funny right now, because it's too cold for it to stick together or stick to anything else. Between wind gusts it's simply rolling down and falling off those roof sections outside my window.

1 comment:

Emily said...

Definitely pellets. Great sound against the window. Glad I have some new woolly items for walking the block up to the mailbox (and more importantly, back, into the north wind).


Good day to stay in.