Wild About Utah

March 10, 2011July 18, 2020

Snowflakes

A free-falling snow crystal photographed as it fell on Alta Ski Area on March 6, 2011, Photo Courtesy & Copyright Tim Garrett, University of Utah — A free-falling snow crystal
photographed as it fell
Alta Ski Area on March 6, 2011
Photo Courtesy & Copyright 2011
Tim Garrett, University of Utah
Alta Snowflake Showcase https://www.alta.com/conditions/snowflake-showcase [Mar 10, 2011] Archive

As winter draws to a close, I’d like to take a moment to reflect on the amazing weather phenomenon that is a snowflake. When winter weather dumps inches of snow on us, it’s easy to overlook the tiny works of art, those intricate and delicate snowflakes, which make up the storm. Snowflakes

Snowflakes – or to use a more scientific term, snow crystals – come in a variety of different shapes including long, thin needles, flat hexagonal plates, columns, and irregularly-shaped pellets called graupel. The International Snow Classification System recognizes ten different shapes in all, only one of which is the traditional snowflake image. The classic six-armed snowflake shape is called a ‘stellar dendrite’ by scientists.

When teaching programs about snow, someone inevitably asks me, “Is it really true that no two snowflakes are alike?” As far as I can tell, the answer is, well, ‘maybe’, and here’s why.

, Photo Courtesy & Copyright — A free-falling snow crystal
photographed as it fell
Alta Ski Area
March 6, 2011
Photo Courtesy & Copyright 2011
Tim Garrett, University of Utah
Alta Snowflake Showcase https://www.alta.com/conditions/snowflake-showcase [Mar 10, 2011]

Three things are needed to form these intricate crystals, and the first two are fairly obvious: water, and temperatures below freezing. The third item is a little more inconspicuous. Water cannot condense and freeze all on its own. Every snowflake needs a piece of atmospheric dust or salt at its core. This particle is referred to as a ‘nucleating agent,’ and it attracts water molecules which then condense and begin to freeze. From there, a snowflake’s overall shape is determined by a number of other variables including the atmospheric temperature, the amount of available moisture, wind speed, and mid-air collisions with other snowflakes.

To add more complexity, consider that each individual snowflake contains somewhere on the order of 10 quintillion water molecules. That’s ten with eighteen zeros behind it. While the way these molecules bind to each other is dictated by the laws of physics, the sheer number of ways in which 10 quintillion water molecules can arrange themselves as they freeze into place is mind boggling. But then again, how many snowflakes do you think fall in the typical March snowstorm in Utah? A lot. One scientist has estimated that the number of individual snowflakes that have fallen on Earth in the planet’s history is ten with 34 zeros behind it. In all of those snowflakes is it possible that two are exactly alike? Yeah, maybe… but good luck finding them!

For more information and some beautiful snowflake photographs, please visit our website at www.wildaboututah.org. Thank you to the Rocky Mountain Power Foundation for supporting the research and development of this Wild About Utah topic.

For the Stokes Nature Center and Wild About Utah, this is Andrea Liberatore.

Credits:

Photos: Courtesy Tim Garrett, University of Utah,
Kenneth Libbrecht, Caltech University
Text: Andrea Liberatore, Stokes Nature Center

Additional Reading:

Halfpenny, J.C and Ozanne, R.D. 1989. Winter: An Ecological Handbook. Boulder, CO: Johnson Books, https://www.amazon.com/Winter-Ecological-Handbook-James-Halfpenny/dp/1555660363

Gosnell, Mariana. 2007. Ice: the Nature, the History, and the Uses of an Astonishing Substance. Chicago, IL: The University of Chicago Press, https://www.amazon.com/Ice-Nature-History-Astonishing-Substance/dp/0679426086

Libbrecht, Kenneth .1999. A Snowflake Primer: the basic facts about snowflakes and snow crystals. https://www.its.caltech.edu/~atomic/snowcrystals/primer
/primer.htm

March 3, 2011March 4, 2026

Graupel Snow

Snow graces the winter sky in many different forms. We have large lazy flakes drifting down, sharp needles driven by harsh winds and thick curtains that swiftly blanket the landscape. Late winter storms offer good chances to observe one of our more unusual and distinctive kinds of snowfall; “graupel”. Graupel – that sounds like some kind of respiratory malady, doesn’t it? Also known as soft hail or tapioca snow, graupel consists of tender round snow pellets no bigger than a pea. The name comes from the German word for hulled grain, “graupe”.

Graupel accompanies warmer winter storms, the kind we often have in March, as well as during summer showers high in the mountains. The pellets form when snow crystals fall through a low cloud of super-cooled liquid droplets. The foggy droplets readily coalesce and freeze around the falling ice crystals, accumulating to form soft graupel pellets. The process is somewhat akin to making rock candy from a concentrated hot sugar syrup, or the method used to generate artificial snow. In contrast, sleet forms when raindrops fall through a cold air layer and freeze.

Our big snowfalls are spawned by storms that generate sprawling unbroken cloud decks. Graupel snow, on the other hand, tumbles down from the bellies of fluffy cumulus clouds. As a consequence, squalls of graupel are brief, the pellets accumulating in a thin white bumpy layer, hence the other common name, “tapioca snow”. A buried layer of tapioca snow is prone to avalanche for the first day or two, after which the pellets anneal and stabilize. Any connoisseur of Utah snow should have graupel in their lexicon of wintry terminology, at the ready to impress any Sun Belt visitor met on the slopes.

This is Linda Kervin for Bridgerland Audubon Society.
Credits:

Photos: Courtesy & Copyright Jim Cane

Text: Jim Cane & Linda Kervin, Bridgerland Audubon Society
Additional Reading:

Wild About Utah pieces by Jim Cane and Linda Kervin

Riehl, Herbert: Introduction to the Atmosphere, McGraw-Hill Book Company, 1972 https://www.amazon.com/Introduction-Atmosphere-Herbert-Riehl/dp/0070526567

Rime and Graupel [link removed Oct 6, 2024. Page formerly found at:] https://emu.arsusda.gov:80/snowsite/rimegraupel/rg.html

Severe Weather 101, How does hail compare to other types of frozen precipitation?, NOAA National Severe Storms Laboratory, https://www.nssl.noaa.gov/education/svrwx101/hail/types/ [added Oct 6, 2024]

American Meteorological Society, Glossary of Meteorology [updated Oct 6, 2024] https://glossary.ametsoc.org/wiki/Graupel

Graupel – What is Graupel? https://weather.about.com/od/g/g/graupel.htm

February 24, 2011June 30, 2020

The Dynamic History of Arches

Hi, this is Mark Larese-Casanova from the Utah Master Naturalist Program at Utah State University Extension.

The Dynamic History of Arches

A “bow-legged pair of petrified cowboy chaps” is how Edward Abbey once described Delicate Arch, that timeless example of Utah’s peculiar geology. In fact, it’s become such an icon that we see it on automobile license plates throughout the state. What we might not realize, though, is that there is nothing ‘timeless’ about Utah’s arches at all.

To help us understand this, let’s go back in time about 300 million years ago. At that time, inland seas routinely flowed into eastern Utah and evaporated, leaving behind a layer of salt that, in some places, is thousands of feet thick. During the next 200 million years, winds, oceans, and rivers deposited a rainbow of sediment layers in southern Utah. These sediments were eventually cemented into sandstones, limestones, and other sedimentary rocks.

Dynamic History of Arches: How nature builds an arch, Graphic Courtesy US National Parks Service — Click Graphic to
Learn How Nature Builds an Arch
Graphic Courtesy
US National Parks Service

Under the weight of all of these rock layers, along with the gradual uplift of the Colorado Plateau around 10 million years ago, the unstable salt layer below flowed like toothpaste. This caused the rock layers above to shift and buckle. Think of it as trying to build a brick house on top of a bed of mud- you would eventually have a house full of cracks.

In some areas, many parallel cracks formed at the surface, and as water flowed into these cracks, the sandstone eroded into tall vertical fins. Some of the fins collapsed over time, and some eroded in just the right way to form an arch. Arches continue to erode and will eventually collapse. But, at the same time, new arches will always form.

There are over 2,000 catalogued arches just within Arches National Park. That’s a lot of arches within such a small area! Within the park, most of the arches have formed in the red, iron-rich Entrada sandstone, however the tan Navajo sandstone also has several. Other rock formations to be seen include spires, mesas, windows, natural bridges, and balanced rocks.

To learn more about Utah’s amazing geologic history, visit Arches National Park’s website at nps.gov/arch or the Utah Geological Survey’s website at geology.utah.gov. And, make sure to visit and explore Utah’s arches as often as you can. After all, they won’t be around forever…

For Wild About Utah, I’m Mark Larese-Casanova.
Credits:

Images: Courtesy US National Parks Service

Delicate Arch, Courtesy & Copyright Mark Larese-Casanova

Text: Mark Larese-Casanova, Utah Master Naturalist Program at Utah State University Extension.
Additional Reading:

Desert Solitaire, Edward Abbey, https://www.amazon.com/Desert-Solitaire-Edward-Abbey/dp/0671695886

Arches National Park, US National Park Service, US Department of the Interior, www.nps.gov/arch/

Utah Geological Survey, State of Utah, www.geology.utah.gov

February 17, 2011January 9, 2023

The Sistine Chapel in Utah

Utah is famous for the beautiful and mysterious rock art found on its colorful canyon walls.

There are two main types of rock art. A petroglyph is an image that is pecked, incised, or scratched into rock. Petroglyphs are often found on rock surfaces coated with desert varnish. The dark stained varnish provides high contrast as the image is carved into the lighter underlying stone.

Pictographs, however, are painted onto rather than carved into a rock surface. Mineral pigments such as hematite, limonite, azurite, and gypsum were used to produce long lasting liquid and solid paints. Paint was applied with brushes, fingertips or hands, with fiber wads and even by spraying or blowing paint. It’s possible that vegetable dyes were also used by ancient artists but these would have been washed away without leaving a trace.

Archaeologists classify ancient rock art into different styles according to image content, drawing techniques, location, and the relationships between various picture elements. The so-called Barrier Canyon Style is well-known in eastern Utah where its greatest level of expression is found.

The Barrier Canyon Style features human-like figures with a supernatural appearance. Torso lengths are exaggerated and shaped like mummys or bottles. Heads may have horns, rabbitlike ears or antennalike projections. Eyes of the figures are often round and staring. Hands, if present, may be holding plant-like images or snakes. Aside from the human-like figures, birds, canines, bighorn sheep, and rabbits are also common in Barrier Canyon Style compositions.

Cultural affiliations of the Barrier Canyon Style artists are still not fully understood. But most archeaologists agree that the artists were part of small bands of nomadic people who roamed the Colorado Plateau between 7500 BC and 300 AD.

Perhaps the best place to view the Barrier Canyon style is in the Great Gallery in Horseshoe Canyon near Canyonlands National Park. The Great Gallery features a 300 feet long mural with over 60 figures. David Sucec (pronounced Soosek)–who is coordinating an effort to photograph and record all Barrier Canyon Style rock art–calls the Great Gallery ‘Utah’s Sistine Chapel.’

So far over 230 different sites featuring Barrier Canyon Style rock art have been discovered. In Utah, look for them in the Book Cliffs area, the San Rafael Swell, around Moab and in Canyonlands National Park.

Thanks to the Red Cliffs Lodge in Moab, Utah for supporting research and development of this Wild About Utah topic.

For Wild About Utah, I’m Holly Strand.

Credits:

Images: Courtesy & Copyright David Sucec
Text: Holly Strand, Stokes Nature Center

Sources & Additional Reading:

BCSProject. https://www.bcsproject.org/about.html

Cole, Sally. 1990. Legacy on Stone: Rock Art of the Colorado Plateau and Four Corners Region. Boulder, CO: Johnson Printing

Repanshek, Kurt. Traces of a Lost People. 2005. Smithsonian magazine. March 2005. https://www.smithsonianmag.com/people-places/lost.html

Schaafsma, Polly. The Rock Art of Utah. 1971, Third Printing 1987, Papers of the Peabody Museum of Archaeology and Ethnology Vol. 65, paper, 169 pp. https://www.amazon.com/Rock-Art-Utah-Polly-Schaafsma/dp/0874804353

Take the Pledge to Protect the Past, Utah State Historical Preservation Office, Department of Cultural & Community Engagement, State of Utah, https://ushpo.utah.gov/shpo/upan/