Frosted by the Weather

When the thermometer starts dipping into negative values at night,  and only rises into the single digits in the day, the morning may come  when our car, smart phone, water pipes, fingers and/or other essentials  have frozen and refuse to work. It’s easy to get so “frosted” by  winter’s hardships that we miss its artistry. Given the right  conditions, though, winter frost can transform the world overnight, with  a breathtaking majesty that would melt any heart.

Naturally, we tend to associate frost with the “bookends” of winter,  when the seasons are changing. The frosted lawn in April or October is  neither unusual nor very interesting, at least not without a hand lens  to see better detail. But mid-winter frost, while not as common, can be  truly extravagant.

The kind of frost that turns any landscape into a winter magic-land  is called hoarfrost, “hoar” being Old English for grizzled. Hoarfrost  occurs in supersaturated conditions when the relative humidity is more  than 100%. This may sound like an impossibility, but in fact it’s  common, at least for short periods of time.          

Warm air can hold much more water vapor than cold air, so as the  temperature falls in a humid air mass, relative humidity increases,  eventually exceeding 100%. Supersaturated water vapor is an unstable  condition, and nature is keen to restore balance by shedding moisture.  On a cool summer evening that would be in the form of dew, and on a  frigid winter night it’s hoar frost.

Those fortunate enough to live in the Thousand Islands region are  treated to hoarfrost often, as the open water provides necessary water  vapor. On occasion, weather fronts can spread moisture, and thus  hoarfrost, over a wide area.

In great literature and children’s stories alike, the theme of  redemptive transformation is both compelling and appealing. Cinderella’s  Fairy Godmother changed a pumpkin into a stagecoach, and mice into fine  horses. She has nothing on hoarfrost, however, which I think must have  learned its craft from the angels themselves.

As water vapor condenses onto cold surfaces, it applies layer upon  crystalline layer of fragile, feathery, exquisite ice forms. Even the  most ordinary and neglected objects—the weed patch, the tangle of rusty  barbed wire—are redeemed by hoarfrost’s magic wand. But given a medium  that’s more complex, more inherently eye-pleasing such as a tree branch,  the effect is all the more inspiring. When that effect is multiplied,  along fencerows and riverbanks, illuminated by morning sun, one has the  urge to kneel on the spot and put a hand to one’s heart.

You can make ersatz hoarfrost by gathering together cold  temperatures, water vapor and a substrate on which to collect ice  crystals. The first is easy—we have plenty of cold these days. Water  vapor, which can be an uncovered stockpot of water fresh off the wood  stove, needs to be concentrated in an unheated garage, enclosed porch or  outbuilding. By definition, every object is a substrate, but more  intricate objects result in more elaborate crystal formations.          

This might have to wait if you first need that pot of boiling water  to thaw out those water pipes, in the crawl space, under your kitchen.  While doing so, please keep in mind that “hoarfrost” is not an  expletive.

By Paul Hetzler

Paul Hetzler is a Horticulture and Natural Resources Educator at Cornell Cooperative Extension, in Canton, NY. He writes a series of humorous and informative essays for a number of newspapers and journals. Subjects range from trees, gardens, insects, native plants, water, wildlife and other natural resources topics. Paul is also the author of "Shady Characters," a collection of humorous nature essays and the unique website “Where the Wild Words Are” – check it out!

Note:  Comments posted on the old TI Life:

Comment by: John Kunz
Left at: 8:04 AM Monday, January 28, 2019

Nice to see some true appreciation of the magic of a north country winter. Love this stuff!!!