Megadunes and Hoar Frost: 6 Facts About Snow

//
This photo of penitentes, ice formations formed in high-altitude regions, was taken in December 2005 along the Chajnantor plain in Chile.
ESO

Piles and piles

Because snow is so fluffy (meaning it's chock full of air), a relatively small amount of water can translate into a huge pile of snow. An inch of rain on average makes about 10 inches of snow. The biggest snowfalls on record are hard to compare, but the Great Snow of 1717 dropped about 3 to 4 feet (0.9 to 1.2 meters) on Boston inhabitants, with some drifts reaching 25 feet (7.6-m), according to the National Snow and Ice Data Center.

In 1959, a snowstorm in Mt. Shasta dropped as much as 15.75 feet (4.8 meters) on inhabitants of the California region, according to the College of the Siskiyous. In the 1998 to 1999 snow season, about 95 feet (28.9 m) of snow fell on Mt. Baker, Wash.

Eyewitnesses to Snowstorm Nemo's Wrath

Graupel and Hoar Frost?

An old saying claims the Eskimos have dozens of different words for describing snow. While that turned out to be a myth, there are many types of snow crystals and even more snow formations. Aside from the snowflake, there's also hoar frost and graupel, according to the National Snow and Ice Data Center.

Hoar frost forms on surfaces that are colder than the frost point in the air around them, so water goes straight from vapor to solid. This spiky, fluffy snow tends to form on tree branches, telephone wires and other skinny items exposed to the chilly air. Graupel, which consists of hard ice pellets, forms when snowflakes fall through a cloud that contains supercooled water droplets. The droplets freeze onto the snowflakes and form misshapen, lumpy balls.

Kenneth Libbrecht, a professor of physics at California Institute of Technology, photographs snowflakes in the field and in his lab. Studio-type lighting, even outdoors, brings out angles, texture and color that are otherwise hard to spot.
Kenneth Libbrecht, Caltech

Snow landscape

While the snow on the driveway may just be a pile, the fluffy white stuff creates beautiful formations in nature. Lovers of winter sports know to be wary of cornices, overhanging snow that juts from the edge of a cliff.

And in Antarctica, giant snow formations known as megadunes form from monstrous snow crystals that are up to 0.75 inches (2 cm) across, according to the National Snow and Ice Data Center. (There can be several snow crystals in a single snowflake.) In arid locales like Death Valley, Calif., piles of snow can be transformed into penitents: bizarre, spiky formations that look like the stalagmites that form in caves.

More from LiveScience:

This article originally appeared on LiveScience. Copyright 2013 LiveScience, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

DISCOVERYnewsletter
 
Invalid Email