Showing posts with label science. Show all posts
Showing posts with label science. Show all posts

Friday, March 6, 2009

Didn't It Snow, Children?

Quel surprise! On Sunday, March 1st, it actually did snow in Alabama. We all had a big time, and a few of us got to wondering about why snowflakes look the way they do.

Snowflake formation begins when water vapor condenses on microscopic dust grains. Each snowflake's unique structure is caused by chemical reactions and ever-changing temperatures.

Snow actually rises before it falls. As a droplet of water vapor rises higher, it freezes into a six-sided crystal. Because ice forms fastest around the edges, cavities form. Faster growth on corners causes branches to sprout, and cavities create interior lines. As the flake rises, temperatures get colder. At 10.4 degrees Farenheit, branches are wide. At 8.6 degrees, new growth is narrower. When the snowflake grows heavy enough to overcome the force of rising air, it falls. As the snowflake falls, warmer temperatures cause more side branches to sprout with longer and narrower tips. Hence, snow.

Some of us waited until many, many of the weighty formations plummeted to earth, then out we went for a rare frozen frolic.

At least one Mr. Possum found the lure of the soft white stuff irresistable, and trotted out for a brief stroll.


©Ramey Channell 2009


Possum In the Snow

Possum has a snowflake stuck to his nose.
His fur keeps him warm when the cold wind blows.
He's on his way home for tea and puddin'.
I asked him to come to my house, but he wouldn'.