Weather
Here’s a blizzard of brrrilliant snow-driven facts…
Whether you love frolicking in the white stuff at the first sign of a snowflake or prefer bundling up and hibernating until the spring thaw, or even if you’ve only ever dreamed of touching a snowball, here’s a blizzard of brrrilliant snow-driven facts…
Mind blown. You can certainly dream of a white Christmas, even if it isn’t strictly accurate. As any good snow pedant will tell you, the ‘white stuff’ isn’t actually white, but rather translucent. It’s the light reflecting off it that makes it appear white with the many sides of the snowflake scattering light in many directions, diffusing the entire colour spectrum. Snow can also appear in a wide variety of spectacular hues. Dust, pollution or cold-loving (cryophilic) fresh-water algae can colour it black, orange or blue. Pink or ‘watermelon snow’, caused by algae containing astaxanthin, a chemical similar to the one found in carrots, was mentioned in the early writings of Aristotle.
One of the determining factors in the shape of individual snowflakes is the air temperature around it. The study of flakes has identified that long, thin needle-like ice crystals form at around -2 C (28 F), while a lower temperature of -5 C (23 F) will lead to very flat plate-like crystals. Further changes in temperature as the snowflake falls determines different shapes of the six arms or dendritic structure of the crystal.
Creator of the Compound Interest science blog, Andy Brunning, has painstakingly catalogued 35 different types of snowflake (plus a few other types of frozen precipitation). They are designated as column, plane, rimed, germs, irregular plus a number of combinations of all of them.
Snowflakes or snow crystals don’t have nuclei in the traditional, biological way (that contains genetic information), but they all do form around one single particle whether that’s a speck of dust or a piece of pollen. This makes it completely different from sleet (which consists of frozen raindrops) or hail (which is sleet droplets that collect water as they fall). This original piece of material that formed the flake can be detected using a powerful microscope.
For decades there have been stories of giant snowflakes falling all over the globe, measuring anywhere from two to six and even, on one occasion, 15 inches across. While many have doubted these reports and pointed out the lack of corroborating evidence, scientists now claim there’s nothing to stop flakes growing that big. As flake size isn’t part of the meteorological measuring designations for snow, these massive flakes may well be out there, but just unreported, unseen or broken up by wind currents as they descend.
Freshly fallen snow absorbs sound waves, giving everything a seemingly hushed, quieter ambience after a flurry. But if the snow then melts and refreezes, the ice can reflect sound waves making sound travel further and clearer.
It’s often stated that the Inuit have 50 words for snow, a fact that was discredited as pure speculation, and then confirmed as roughly accurate. No matter how many they actually have, it pales in comparison to the Scots. Researchers at the University of Glasgow claim that the Scots language has 421 terms related to the white stuff, including ‘skelf’ (a large snowflake), ‘spitters’ (small drops of driving snow) and ‘unbrak' (the beginning of a thaw).
Speaking of language, you must be careful if you’re ever tempted to refer to a snowstorm as a ‘blizzard’. Snowfalls must meet a strict set of stipulations to be considered a blizzard. Visibility must be below 200m while the wind has to reach speeds of around 48kmp (30mph).
According to Nasa’s scientific simulations (corroborated by remote robots on the planet’s surface), during the summer in the north of Mars there may well be sudden, violent snow storms. We know there are clouds and subsurface ice on Mars, so snow is certainly plausible. Scientists also detected a cloud of carbon dioxide snowflakes over the southern pole of the planet.
Don’t think for a second we are the only mammals to enjoy a good snowball fight. Japanese macaques, also know as ‘snow monkeys’ have been observed making and playing with balls of snow. Young macaques appear to enjoy stealing each others snowballs, then battling to retrieve them.
Spend too much time on the slopes and you could suffer from piblokto or ‘Arctic hysteria’, a disorder affecting Inuit people living within the Arctic circle. Symptoms include meaningless verbal repetition or performing irrational or dangerous acts, followed by amnesia of the event. Vitamin A toxicity is thought to be one source of the disorder, though in recent years researchers have questioned whether the illness, thought to be based on as little as eight cases, actually exists at all.
One psychological condition that definitely exists is chionophobia, or a fear of snow, deriving from ‘chion' the Greek word for snow. While the phenomena can develop due to a childhood trauma involving snowy accident, there are more irrational variations where people develop an acute fear of becoming trapped or buried in snow if there isn’t a flake in sight or at the first sign of a flutter.
The great explorer Ernest Shackleton was renowned for his bravery, intrepid spirit and loyalty to his comrades. But the contents of his medical kit during the Nimrod Expedition sounds more like the rider for a 70s rock band than a polar exploration. Colic was treated with cannabis, diarrhoea sufferers enjoyed the delights of opium while those stricken with snow blindness, a temporary loss of vision due to overexposure to the sun's UV rays, would have cocaine dripped directly into the eye.
There are a number of factors that can trigger an avalanche, but noise isn’t one of them. Weight is a much more important contributor. A sudden deluge of snow, an increase in wind speed or even the over-zealous footstep of a skier can trigger a sudden, deadly, cascade. But a loud burst of terrible singing, that won’t have much of an effect.
Because snow is comprised of 90 to 95 percent trapped air, it means it’s a great insulator. This is the reason many animals burrow deep into the snow during winter in order to hibernate. It’s also the reason that igloos, that use only body heat to warm them, can be 100 degrees warmer inside than outside.
Usually, the air temperature needs to be around the freezing mark for snow to form, but if rain falls for long enough it can cool the air around it as it falls and eventually create the right environment to produce flakes. So the temperature can be as high as 6°C on the ground and snow can still be falling.
Snowflakes can fall at a speed anywhere between a leisurely one to a breakneck 14 kpm (9 mph), depending on the environmental conditions in the air as they drop. Snowflakes gathering water as they fall and wind direction can speed up the descent. It takes roughly an hour for a flake to leave its cloud and reach the ground.
Featured image by Malorny | Getty
