Nature is amazing. There is no doubt about that. People have marveled at nature’s beauty since they came into existence. Not knowing what was happening, these people of old came up with some truly magnificent stories, trying to give a sense to the world around them. Today we are blessed with more knowledge about the world, but nevertheless this doesn’t diminish the magic taking place before our very eyes. If anything, it only makes nature more interesting.
And while we no longer believe the “sky to be falling” every time it’s raining, or that Thor is smiting his hammer with every lightning strike, there are some natural phenomena out there we common folk still don’t understand. Here are 10 such natural occurrences, explained by our most prized of storytellers: scientists.
10. Snow Rollers
No, these weren’t made by gnomes during the night, but rather by a series of meteorological events, in a particular order. Snow rollers aren’t a common sight, but when they do happen, and you stumble upon some of them, be sure that a fairly unlikely series of events took place the night before. First and foremost there needs to be two separate layers of snow already present: a first, icy or crusty layer of snow underneath, and a wetter one above. This way, the wet layer has something on which to roll over. Then you need some wind, strong enough to scoop out balls of snow and push them forward, similar to a tumbleweed, but not so strong as to blow it apart.
They will also form in relatively sloped areas, but this is not absolutely necessary. Just imagine yourself making a snowman, and the process is more or less the same. The biggest differences are that one is made by a person, the other by the elements. Also, snow rollers are more often cylindrical in shape, rather than a sphere, and they can vary in size from that of an average snowball, to that of a car. Nevertheless, the many meteorological conditions which need to take place in that exact order, at the exact time, make these snow rollers a very rare phenomenon to behold, and they usually make headlines in the newspapers the following day.
9. Mammatus Clouds
Looking very ominous, mammatus clouds are sometimes the harbingers of an imminent and powerful thunderstorm. But more often than not, they form just after the storm has passed. Also known as mammatocumulus, they translate to “mammary cloud” due to their appearance as pouches, usually hanging beneath a larger, anvil cloud. As updraft pushes precipitation enriched air to the top of one such anvil cloud, the air begins to spread out, and the heavier precipitation, usually water particles and ice fall back to the bottom, forming these mammatus clouds. As the air falls back down to the ground, it heats up, evaporating the precipitation within it. The more precipitation there is the further down they will sink.
These clouds usually span over an area of several hundred miles in all directions and last for about 10-15 minutes at a time. While they usually form underneath an anvil cloud, they also appear on occasion under altocumulus, altostratus, stratocumulus, cirrus clouds, as well as volcanic ash clouds. Whatever the case, they look amazing and ominous at the same time, especially when sunlight is reflected off of them.
8. Ice Flowers
This natural phenomenon in particular is as beautiful as it is rare, and only takes places in late autumn or early winter, before the ground freezes over. As the air goes below freezing point, the sap within some plant stems, plants like the Frostweed (Verbesina virginica), begins to freeze and expand, pushing through the plant itself and forming an amazing thin sheet of ice, similar to a flower petal. Certain conditions need to take place for this beautiful phenomenon to appear. As the ground is still unfrozen, water keeps on going up the stem and through the microscopic cracks, the sap escapes and transforms into ice, adding to the ever longer sheet.
In some instances, this phenomenon can happen to wood as well. Wood which hasn’t yet dried completely and is kept in freezing conditions can sometimes present these Ice Flowers. More often than not however, the wood cracks from the pressure within, generating these wonderful patterns which curl and fold into gorgeous frozen petioles, giving this phenomenon both its name and appearance.
7. Columnar Basalt
This type of rock formation occurs, as it name suggests, in basalt, which is a lava flow rock. These formations can be found all over eastern Washington state, Devils Tower in Wyoming, Giant’s Causeway in Northern Ireland, or the Los Organos on the northern part of La Gomera Island in the Canaries, and many other places around the world. Based on their name, you can clearly see what kind of stories people used to give these, back in the day. Nevertheless, there are columnar basalt formations found even on Mars. The way these form, is similar to how the ground cracks during a severe drought. As the water evaporates, or goes into the water bed below, the ground above contracts and cracks. The same thing applies here, as the lava flow progressively cools over a period of maybe longer than 100 years. The cracks form perpendicular to the original flow direction.
The difference in thickness of these columns depends on the speed at which they cool. While there are cases of a lava beds contracting as a whole, it is more likely for them to crack. The faster they cool, the thinner the columns will be. And while hexagons are most common, polygons with three to twelve or more sides can be observed. Their length, which can be greater than 50 feet, is based on how thick the original lava flow was.
6. Fallstreak Hole
This particular cloud formation looks as if someone took an enormous cookie cutter and made a hole in what, otherwise, looks like an enormous flat cloud covering the sky. In fact, some people call them Holepunch clouds. Another particular aspect here is that a streak of cloud usually hangs underneath that hole. What’s happening up there is quite interesting, to say the least. For starters, we need to know that air at higher altitudes is much cooler that the temperature at the ground level. In fact, temperatures can go well below freezing point.
But despite this, water vapor and tiny water droplets “refuse” to freeze and remain in a “supercool” state. Water usually begins to freeze due to the impurities inside it: salt, dust particles, all sorts of other minerals, and so on. Cold, distilled water can also begin to freeze instantaneously if a piece of ice is added to it, in a process known as “ice nucleation.” Since water vapor is quite pure, water stays in liquid form even under freezing temperatures. Here, a piece of ice falls from higher altitudes and comes in contact with the water inside this cloud. This in turn sets out a chain reaction, freezing the droplets around, and making them fall to the ground - thus, the cloud streak below the hole. If a plane happens to pass through a cloud at a shallow angle, it can also cause it to freeze and form a cigar-shaped Fallstreak hole.
5. Brinicles
Brinicles are a fairly rare sight to see, not because they rarely happen, but because they take place underwater. In fact, they were only discovered in the 1960s. When seawater freezes, it releases its salt, creating super-salty brine. This percolates through cracks in the ice, into the water below. This brine then sinks because it’s much denser than the surrounding water. That is also the reason you can float in salty water, far better than in a fresh water lake. Nevertheless, this brine is also much colder, and the seawater around freezes on contact. Over time, this creates somewhat of an inverted cone, or funnel if you will, which goes ever deeper towards the bottom. This stalactite is what’s known as a brinicle.
Since brinicles appear in shallower waters, closer to the coast, in a course of some 12 hours it’s able to reach the bottom, trapping everything in ice. Creatures usually living on the ocean floor, like starfish and sea urchins, move far too slow and they get trapped in this newly formed ice, which then spreads along the bottom. Not surprisingly, brinicles are more commonly known as “The Ice Fingers of Death.”
4. Volcanic Lightning
Also known as a dirty thunderstorm, volcanic lightning is a weather phenomenon related to the production of lightning in a volcanic plume. What causes them was somewhat hard to figure out, and is still not yet fully understood. While during a thunderstorm, lightning is caused by colliding ice crystals, which generate enough electricity to cause a lightning bolt, ash clouds are far more difficult and a lot more dangerous to study. At first glance, it would seem counter intuitive to attribute ice as the main culprit behind a “dirty thunderstorm”. Some new scientific studies and better equipment, however, have begun to show us what’s really happening during one such volcanic inferno.
Once an eruption begins, large quantities of positively charged particles are blown into the air, which in contact with the negatively charged air particles around make for an electric discharge. These lightning bolts occur in and around the plume, which is ejected by the volcano itself. At first this theory was mostly based on speculation, but thanks to the very high frequency (VHF) radio emissions technology, scientists were able to get a better look inside one such dense volcanic plume and figure out what’s actually happening. But this is not all when it comes to lightning and volcanoes together.
Another study has tracked the location of lightning strikes some 60 miles from the eruption, and at near-stratospheric heights of about 12 miles above the ground. This seems to be caused somewhat in the same way as in a usual thunderstorm. As the ash cloud is blown by the wind, it thins out, and ice begins to form at its extremities, resulting in further lightning strikes. These studies, while not that surprising, can help a great deal in aviation as they can inform on the way to properly respond to a volcano eruption and the usual flight paths of commercial airliners passing above.
3. Sailing Stones
Death Valley in California is notorious for its scorching heat during the day and extreme cold during the night. Among the many mysteries and legends linked to this place, none is more fascinating than the “sailing stones” phenomenon taking place within the Racetrack Playa, an exceptionally flat and level scenic dry lake. Some weighing around 700 pounds, the stones which dot the lake bed seem to be moving across the desert floor when nobody’s watching, leaving long trails behind them. This has puzzled scientists for decades now, but now geologists Richard and Jim Norris, believe they have found the answer. Though the phenomenon itself was under scrutiny since the 1940s, only recently did the two geologists actually capture these sailing stones on film. They set up a weather station in the area and fitted stones with GPS trackers. Two years into the project, the stones began to move.
What actually happened was that it rained the day before, and during the night a thin layer of ice had formed over a few inches of liquid water. As day came, the ice began to break apart and, pushed by the breeze, these ice sheets simply dragged the stones with them, scraping a trail on the bottom. By the end of the day, when all the ice had melted, some of the stones moved more than 200 feet. However, the conditions for this phenomenon to take place are hard to come by, and Norris compared the chances of actually stumbling upon it with winning the lottery. This also explains why this seemingly simple occurrence has intrigued people for so long.
2. Penitentes
Penitentes are narrow ice formations, commonly found at high altitudes of over 13,000 feet, with low humidity, especially in the Andes Mountains of South America. What’s curious about them is that they usually point towards the sun, ranging from a few inches to six or even 16 feet in height. Their name comes from their resemblance to people kneeling, as when doing penance. More precisely, they resemble the brothers of the Procession of Penance in Spain, who wear hats with very tall, narrow, and white sharp tips (just like the KKK).
Anyway, the existence of these Penitentes was known about as early as the 1800s and were originally believed to have been formed by the wind. But in fact these jagged snow structures are the result of dimples in the original snow sheet. These in turn result in ever larger ablations, through a process known as “sublimation” - where ice and snow melts and vaporizes without turning into liquid water first. This happens more easily at high altitudes due to the reduced pressure of the atmosphere, together with the lower temperatures of the air and the more powerful rays of the sun above. The Penitentes are what remains behind, thanks to their angle towards the sun.
1. Light Pillars
This stunningly beautiful light show usually makes an appearance in cold, arctic regions and can be described as optical phenomenon in which columns of light seem to emanate below or above a light source, in a vertical orientation. This light source can be of natural origins, like the sun or moon, in which case these light columns are called Sun or Lunar Pillars, respectively. Or, they can occur due to the presence of artificial lights as well. These light pillars form when the two astral bodies are close to the horizon and tend to take on the color of the body emanating that light in the first place.
The effect itself is created by the reflection of that light onto the many ice particles suspended in the air or clouds. Because of this, light pillars fall in the category of halos - optical phenomenon produced by light interacting with ice crystals. The reason for why they appear vertical and not as a circle, is because the ice crystals which reflect them consist mostly of flat, hexagonal plates, which tend to orient themselves more or less horizontally as they fall through the air. Together they act as a giant mirror, reflecting the light either up or down. Thanks to the slight turbulences in the air, these ice crystals somewhat change their horizontal orientation, elongating the light column even further. The larger the crystals, the more pronounced this effect becomes. In some rare cases, column-shaped crystals can cause light pillars as well.
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