It is the life of the crystal, the architect of the flake, the fire of the frost, the soul of the sunbeam.
This crisp winter air is full of it.
-John Burroughs, "Winter Sunshine"
To Winter William Blake (from Poetical Sketches, 1783
O winter! bar thine adamantine doors:
The north is thine; there hast thou built thy dark
Deep-founded habitation. Shake not thy roofs
Nor bend thy pillars with thine iron car.
He hears me not, but o’er the yawning deep
Rides heavy; his storms are unchain’d, sheathed
In ribbed steel; I dare not lift mine eyes;
For he hath rear’d his sceptre o’er the world.
Lo! now the direful monster, whose skin clings
To his strong bones, strides o’er the groaning rocks:
He withers all in silence, and in his hand
Unclothes the earth, and freezes up frail life.
He takes his seat upon the cliffs, the mariner
Cries in vain. Poor little wretch! that deal’st
With storms, till heaven smiles, and the monster
Is driven yelling to his caves beneath Mount Hecla.
The ethereal beauty and benefits of snow
Snow offers some nice benefits to your garden and plants besides its unmatched beauty.
By Betty Earl | January 6, 2011 Although winter is usually remembered for its punitive conditions, it can also be a period of immense beauty.
While people’s opinions may vary greatly on how truly desirable snow is – in particular, the recent days when the newspapers and TV newscasts were full of stories of stranded travelers and unplowed streets – snow actually has many benefits.
The unmatched beauty of snow But most important, a fluffy layer of snow brings an immense beauty to the winter landscape, turning it into an enchanting winter wonderland. All of nature is transformed, light is altered, and a stillness that’s unknown the rest of the year settles in.
For me, there’s something magical about the big, flaky, soft kind of freshly fallen snow. I stop to take in the beauty of the pristine landscape, and try hard to capture the fairytale scenery with my camera.
Some of this artistry can be seen and touched, some can only be felt, and no matter how hard I try, the pictures never ever capture any of that allure the same way I see it or feel it.
Walking out into the yard, I stop and listen to the silence. It’s quiet and serene – peaceful and in a strange way, absolutely perfect.
There is a sort of mystical peace in the snowflakes as they fall. I love the way the morning sun glistens off the snow cover as if someone had sprinkled diamonds over the area.
Just listen! Listen to the sound snow makes as it packs under your boots or the low, velvety swish of car tires on unplowed streets
So savor the moment! To my mind, snow cover makes a winter garden – complete.
Snow and ice crystals
Yoshinori Furukawa and John S. Wettlaufer
December 2007
Vast regions of our planet are seasonally or perennially covered with snow and ice; the ground becomes rock hard, lakes and oceans freeze, and snow falls from the sky.
If you live in New England or Hokkaido, look out the window in winter and you will see those inescapable consequences of Earth’s seasonal cycles.
For nearly everyone, snow crystals induce a visceral response, be it an annoyance during one’s commute or the enthusiasm of an impending ski trip.
The distribution of ice throughout the universe and close to home has central implications in astrophysics and geophysics—from the agglomeration of matter in stellar nebulae to the state and fate of Earth’s climate.
Like all materials, ice exhibits basic phase-transition phenomena. But its study does not require ultrahigh-vacuum or cryogenic apparatus, so it is an ideal test bed for physicists.
Snow crystals are simply ice crystals grown from the water vapor present in air, and the varied forms they take during their transit through the clouds are the basis of science, art, and the culture of cold regions. In his 1611 book A New Year’s Gift of Hexagonal Snow, Johannes Kepler considered the origin of the hexagonal shapes of snow crystals, like those shown at left in photographs taken by one of us (Furukawa). Kepler argued that the hexagonal form had to do with the packing of spheres, an idea that led to his famous conjecture on the densest possible filling of space by spheres. During the winter of 1635, René Descartes made strikingly detailed observations of snow crystals. Three centuries later the most extensive catalog of its time was made by the Vermont farmer Wilson Bentley, who published the book Snow Crystals with William Humphreys in 1931. Bentley’s dedication and passion were evident: “Was ever a life history written in more dainty or fairy-like hiero-glyphics? How charming the task of trying to de-cipher them.”
The snowflake has substantially shaped the fabric of life in Hokkaido, the northern island of Japan. The imagination of Hokkaido University nuclear physicist Ukichiro Nakaya was captivated by Snow Crystals, and in 1932 he began his own observational program. In the course of taking more than 3000 photographs in a few years, Nakaya classified snow crystals into some 40 morphological categories. He surmised that the shapes were a consequence of the temperature and supersaturation of the atmosphere through which the crystals moved, and he quantified his intuition by creating nearly all of the natural morphological categories in the laboratory. His results, which have since been reproduced by his students and by many others around the world, are elegantly summarized in the so-called Nakaya diagram that appears on the next page. In the diagram, one can read the meteorological information written on a snow crystal. That is, one can infer much of the temperature and humidity history of the snow crystal by observing its morphology on the ground. Hence, Nakaya was often quoted as referring to the snow crystal as “a letter from the sky.”
Much of the focus on snowflakes deals with the highly dendritic forms, but physicists generally understand how such shapes arise out of diffusive instabilities associated with the vapor, as mediated by the underlying anisotropy that shapes the inner hexagonal form. Nakaya clearly appreciated that the complex spacetime history of an object in a turbulent, nonequilibrium environment cannot be captured in its entirety. Nonethe-less, the Nakaya diagram embodies the basic physics associated with the principal dynamic shape transitions, even if it doesn’t include all snow crystal forms. One of its salient features is that, depending on the temperature regime of growth, the forms at small supersaturation are either hexagonal plates or prisms, and the transitions from one regime to the other are abrupt. For some 50 years, many researchers have grappled with the challenge of explaining that alternating plate-prism growth sequence.
A crystal’s facets reflect the symmetry of the underlying crystal structure. And its surface energy depends on the sum of the energies of all the bonds broken per unit area during the creation of its surface by cleavage. Strictly speaking, facets, beautifully reflected in the crystals at the bottom of the Nakaya diagram, are orientations that are smooth on all scales down to the molecular scale.
An ideal, dislocation-free crystal is fully faceted at absolute zero and becomes rougher as its temperature increases. Some facets persist right up to the bulk melting point Tm, and some become rough at lower temperatures. The surface roughness, its equilibrium and nonequilibrium manifestations, and liquidity itself all conspire to influence the transitions on the Nakaya diagram. Here we point out the essential ingredients of the conspiracy.
