The sometimes bizarre, but always fascinating, World of Ice
In the final installment on ice and its myriad forms, we will examine several exquisite examples of these cold-induced crystalline structures.
I should emphasize that when we speak of ice in this article, we are talking about one of the three primary states of water; liquid, gas and solid.
Although ice has more than 300 known forms on Earth, there are now five known states of water. The last two of which are exotic and a little hard for even scientists to wrap their brains around.
Since we all understand and can easily observe water as a liquid, gas and solid, the two exotic states require a brief explanation.
A fourth state of water was discovered at the Oak Ridge National Laboratory in 2016. When water is exposed to extremely high pressures, such as when trapped in a crystalline mineral like beryl, it reacts in a bizarre way called “tunneling.”
This next part is a mind-blower, but here goes.
In tunneling, a water molecule faced with a solid barrier can elect to be simultaneously on one or both sides of the barrier, or anywhere in between.
Yes, you read that correctly!
This would be like you walking up to a brick wall and passing right through it or be on both sides of it at the same time. It defies logic. But much of quantum physics does make a huge detour from common sense.
This phenomenon has only been observed previously in subatomic particles, not something as immense as a molecule. This revelation should cause your eyes to widen and your brain to follow suit.
The fifth state of water also has a subatomic analog and occurs when bosons (subatomic particles) are cooled down to near absolute zero.
This unique state of water is called a Bose-Einstein Condensate, and has many commercial and scientific research applications, such as atomic clocks, lasers, and highly sensitive magnetic sensors.
Ice generally occurs when it reaches a temperature below 32 degrees Fahrenheit or zero degrees Celsius. We’ve all been taught this in school.
However, this is not a hard and fast rule.
Many environmental factors affect the transition of liquid water to ice. For example, air bubbles and contaminants such as dirt in water can require even lower temperatures to achieve a solid state.
And, even after it is frozen, there is limitless potential for further metamorphosis imposed by changing environmental factors such as pressure, elevation and fluctuating temperatures.
In a previous column about snowflakes, we learned that a nucleus is required to stimulate water droplets to freeze into a hexagonal plate, the basic structure upon which elaborate snowflakes are formed.
Likewise, water can be super-cooled to temperatures below 32 degrees Fahrenheit and remain a liquid. When we introduce a substance like a tiny particle of matter, it can go straight to ice nearly instantaneously.
OK, enough of the brain-taxing science and on to the elegant structures of water we call ice.
Needle Ice – like walking on potato chips
If you have done any winter hiking, chances are you have seen needle ice. Perhaps, like me, you have walked upon these long narrow columns of ice that crunch like potato chips.
And maybe you have even marveled at the surprising amount of dirt, leaf matter, acorns, and other forest debris elevated skyward upon these delicate tendrils of ice.
As we all know, ice has tremendous strength – think of copper water lines splitting open during sub-zero temperatures. In days past, it was not uncommon for engine blocks to crack when an insufficient amount of anti-freeze was in the radiator.
For needle ice to form, conditions must be just right; soil temperature above 32 degrees F and air temperature below freezing. When this happens, often during the night, water is brought to the surface by capillary action, freezing upon contact with the colder air.
Under these conditions, a needle-like column begins to form vertically. One can observe thin horizontal lines in the ice structure by kneeling down and taking a close look. These strata lines indicate warmer daytime temperatures when the ice starts to melt, only to freeze again overnight.
Rime Ice and Hoar Frost – beautiful and sometimes deadly
To be sure, it is hard to tell the difference between rime ice and hoar frost; they are so similar in structure. Both are stunningly beautiful, but the difference lies in the conditions in which they are formed and the havoc that they can wreak.
Before further discussing rime and hoar, we need to define an essential and fascinating term, sublimation. Simply stated, sublimation is when water transitions directly from ice or snow to vapor, bypassing the liquid form altogether.
An excellent example of sublimation is dry ice (frozen carbon dioxide). If you placed a chunk of dry ice on a plate at room temperature, it would transition directly from a solid state to vapor. In contrast, an ice cube will leave a pool of liquid water, which then must evaporate.
The same happens in hoar frost formation on a clear cold night. The water vapor sublimates directly to ice upon contact with objects such as power lines, fences and other structures.
On the other hand, rime ice forms when water droplets in fog freeze upon contact with objects that are below freezing temperatures. Icing is a significant concern in aviation. The buildup of ice on an airplane, particularly the leading edges of the wings, can bring the aircraft down with catastrophic results.
Some may remember the crash of Air Florida flight 90 on January 13, 1982. Failure to de-ice the wings caused the plane to plummet into the Potomac River in Washington, D.C., smashing into the 14th Street Bridge and killing 78 passengers and crew members.
Rime ice can take several forms, soft, hard and clear. The soft form exhibits exquisite, delicate feathery structures that collapse upon touching, much as hoar frost does.
The other two heavier and tenacious forms of rime are responsible for bringing down not only planes, but entire trees can be toppled by the weight of rime ice, often causing power outages and property damage.
Rime ice is referred to as “nature’s pruning shears.” Like forest fires, the pruning effect of rime ice can help maintain our forests’ health.
Rime ice is responsible for some of the most bizarre and fascinating ice displays. One cold winter several decades ago, I was cross-country skiing with friends in Dolly Sods.
Upon arriving in the “Sods,” we noticed that rime had developed on the “one-sided” spruce trees to such a degree that it felt like we were skiing among massive frozen waves.
These cold and frozen waves are reminiscent of those depicted in Japanese ukiyo-e prints by the artist Hokusai.
The experience was surreal and memorable for all involved.
Nilas Ice, Pancake Ice, Growlers, Floe and Bergy Bits
In our part of the world, we can only enjoy outdoor ice formations during the coldest months of the year. But Antarctica has an ever-changing panoply of ice formations with fanciful names like Pancake Ice, Nilas Ice, Growlers and Bergy Bits.
Most of us will never get the opportunity to see these exotic ice formations. Of course, we can always see them in online images, but a reader, Doug Lucchetti, has been up close and personal with polar ice.
Doug worked at McMurdo Research Station in Antarctica and spoke eloquently of the strange and fascinating ice formations he encountered there.
“On occasion, we’d get to joy ride out to the ice caves a few miles north of the station where a glacier from the sides of Mt. Erebus extended out into the relatively shallow waters of McMurdo sound forming what is called an ice-tongue a mile-long.
“Along its side were numerous caves formed when crevasses would open up large enough to crawl into, and then one would be out of the super cold air and into the relatively warm still air of the cave.’
“The light in an ice cave is, of course, filtered by the ice, and so it is that distinctive characteristic blue we associate with ice and water; the deeper we went in, the darker the blue until it became an electric cobalt hue.
“It was also relatively high in humidity since it was floating on seawater or at least proximal to it. As a result, clusters of ice crystals would form like a cluster of flowers.
“Some of the ice crystals would grow to dinner plate size and display a kind of 3-dimensional growth in step-like layers, almost like one sees in those bismuth crystals you can find in museum gift shops. Another ice form would be in the shape of long, really long threads like speleological helictites.”
Is there ice in outer space?
Of course, there is.
Our water here on Earth, our oceans, rivers, lakes and streams, came from outer space. Water arrived here in small amounts over billions of years on things like icy comets and other interlopers from far out in our solar system.
Scientists are discovering many new and bizarre forms of ice in our solar system. Particularly so on the icy moons of planets like Jupiter’s moon, Europa and Saturn’s moons, Enceladus and Titan.
But the strangest discovery of all is something called cryovolcanism. This volcanic anomaly was observed on Neptune’s moon, Triton, as the Voyager flew by in 1989.
Many a child in grade school has made a paper-mache volcano for the science fair. An eruption of magma is simulated with vinegar, baking soda and food dye.
Yet, even those young scientists know that a real volcano spews molten rock, something called magma.
The cryovolcano spotted on Triton demonstrates that volcanoes existing there spew out ice rather than magma. In this case, the expelled ice reached heights of nearly five miles.
We have nothing comparable on Earth, and the mechanics of cryovolcanism is yet to be understood. Maybe one of those young students mentioned earlier will figure out the mystery.
I have always maintained that our world is much stranger than even our best science fiction writers can imagine. And the only way we will ever know of such wonders of nature is through the many disciplines of science.
P.S. There is only so much space in the newspaper for photographs, so I have assembled a small portfolio of fascinating images of ice that I would gladly share with any interested reader.
Citations are available upon request.