What is more beautiful than the high mountains, wrapped in a white blanket of snow? They, like giants in fluffy hats, as if trying to reach the sky. Many tourists like to go on vacation to the mountains in the cold season. Everything around is white and white, his chest is bursting with pure frosty air, and all the greatness of winter in the mountains appears to his eyes. However, is snow always white? What if it is painted red?
The first theories of the appearance of red snow
In the IV century BC, the famous Aristotle in his work called "Meteorology" described a very unusual phenomenon. Already at that time, people noticed that in the winter in the mountains sometimes snow falls red. However, no one could explain the exact cause of this phenomenon.
For two centuries people puzzled over why this is happening. Whatever they suspected: metals that fell from the sky, and migratory birds, and chemical reactions involving alkalis, and precipitation. Surprisingly, when considering the version with birds, no one could say where did the carcasses of birds that subsequently sprinkled with their blood huge snow expanses disappear.
What does red snow look like?
Those who contemplate such a phenomenon sometimes do not find words to describe their feelings. On the one hand, there is a feeling of unreality of what is happening, and on the other, a person is overwhelmed with delight, it seems to him that he has touched something unknown, one might say magical.
Many are afraid to step on the red snow, because it seems to them that in this place there was some kind of deadly battle, as a result of which everything is now flooded with blood. Eyewitnesses also say that such snow resembles watermelon pulp and even smells like this amazing delicacy.
Expedition D. Ross
In the first half of the 19th century, the correct explanation of such a natural phenomenon as red snow was first voiced. The Englishman John Ross went on a long expedition across the Pacific Ocean. When the ship sailed near Greenland, the team drew attention to the red streams flowing down the mountain slopes. Against the background of white snow, it looked more than strange. John Ross became very interested in this phenomenon and decided to go ashore to collect samples of burgundy fluid. In 1818, after a consultation of scientists, an expedition report was published. The red snow, whose photos still fascinate people today, turns out to be easily explained: ordinary algae became the cause of this phenomenon.
What does modern science say?
So, now it has become clear why red snow falls in the mountains. Chlamydomonas nivalis ("snow" algae) is a green freshwater algae, which includes not only chlorophyll, but also a special red carotenoid pigment, designed to protect them from ultraviolet rays and radiation. In addition, it absorbs heat well.
"Snow" algae are distinguished by the fact that they grow exclusively in a cold environment. Throughout the winter, they hide under snow cover, and with the arrival of heat they begin to become more active, which is greatly facilitated by the abundance of sunlight. As already mentioned, the carotenoid pigment absorbs heat, so the snow surrounding the algae melts much faster. When the snow algae blooms, the snow turns into water so quickly that these streams, turning red, rush down. Many eyewitnesses to this phenomenon talk about how they saw the mountains cry with bloody tears.
However, over time, nutrients are exhausted in the surrounding area, as a result of which algae fall into a kind of hibernation, forming thick-walled cells. But with the advent of spring, the whole process will be repeated again, and again people will be able to observe this amazing natural phenomenon.
