How can moss tolerate cold and frosty winter temperatures?

Okay, so far as I've researched, the reason why moss can tolerate freezing temperatures is that moss has a natural anti-freeze (glycerol? sucrose?) in its cells! This lowers the temperature at which water freezes, thus preventing damage to the plant cells.

What is the beginning shape of an ice crystal ?

Water vapor, when frozen, forms crystals that begin as hexagonal prisms. These prisms can be flat small plates, or tall thin columns. These hexagonal prisms will change in shape as temperatures fluctuate, and/or particles of dirt/dust combine with the water vapor.

How do frost crystals keep "growing" when conditions are right?

Frost crystals, or surface hoar, forms when temperatures are cold and water vapor is available. These frost crystals continue to "grow" when daytime temperatures are warmer than freezing, which warms the snow up, and then, as the night air cools the snow, water vapor evaporates from the snow and recrystallizes on the surface. If conditions are just right, hoar frost can get quite large!

What causes the frost on car windshields to vary so much?

Windshield frost occurs when water vapor is available and temperatures are freezing. The patterns that form vary due to residue on the glass, scratches on the glass, and variations in temperatures!

Go to snowcrystals.com for LOTS more information on frost and snowflakes!