Water transformations in Lake Baikal

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A lot was said about water and a lot will be. But it is worth considering the cases, at least briefly, of the water other manifestations that are quite numerous: ice, snow, steam, fog, hail, etc. There is also the so-called heavy water in Lake Baikal. Its discovery is rather interesting. In 1932 American scientists G. Urey and E. Osborn found out that even in the purest water that only can be obtained in a laboratory there is a small amount of a substance, that apparently, have the same chemical formula H2 O, but having a molecular weight of 20 instead of 18 that is a characteristic of ordinary water. G. Urey called this substance heavy water. The big weight of heavy water is explained by the fact that its molecules are composed of hyderogen atoms with a double atomic weight in comparison with ordinary hydrogen atoms; it is called deuterium. And there is tritium that is even heavier, and it is a superheavy hydrogen isotope with one proton and two neutrons in the nucleus. Tritium oxygen compound forms superheavy water. Heavy water looks like ordinary water, but it differs from it in many physical properties. Specialists believe that in the Lake Baikal radioactive tritium can be found though in small amount but still.

The ice on Lake Baikal is a usual thing. You can see it in October close to the beach, and you can observe it in July. On my journey to the north-east I saw the shore ice that resembled rock salt in its crystalline even on July 8, 1990! But the usual time of ice onset on Lake Baikal is approximately mid-January, and its complete opening takes place in early May. Ice onset of ice deadline can vary from December (like it happened in 1877) to February (like in 1959), and its opening comes sometimes in April (like in the year of 1923 it took place on the 7th of April) or in May (in 1879 it took place on the 26th of May). It goes without saying that these dates may vary even more in the north and the south of Lake Baikal.

When the ice is onset in a calm, windless time, it forms a huge area in some places that boys call gololyadka (in English – “glazed frosty”). It strikes by its outstanding characteristics. First, by its polished surface gololyadka can compete with the mirrow shiny surface. It is great pleasure to skate, ride scooters (i.e., a structure with three skaters raced to high speeds with the help of metal peaks) or just slide with boots on it. Second, the ice transparency is amazing; it is “as pure as a tear”. The ice crystal purity completely changes the perception of its thickness: masking one step onto sufficiently thick ice surface you often seemes to go on one millimeter ice-crust that is about to break through under your feet. This feeling is intensified by the fact that under the ice layer one can see the attributes of water depths: the ribbed sand dunes, aquatic plants and rocks, as well as fish rapidly sailing away from a mysterious top enemy.

The invariants of ice evoke particular interest. In rapid rivers flowing into the Baikal and out of it and in the lake itself there is the so-called frazil ice, or intrawater ice. It became known in the XVIIIthe century (1730) when the Englishman Hel saw it at the bottom of the Thames. The frazil ice forms in early winter on those parts of the river that have not yet frozen and covered with ice; here open water surface gives off heat into the atmosphere intesively and the water becomes too cold (a few hundred degrees below zero). In such places ice onsets not only on water surface, but also across the whole width. In this process heavy current is also necessary for intensive mixing. That is why the most suitable place for the frazil ice formation is river places unfreezing and rapid and such places are sometimes called frazil ice factories. When it comes on the surface the frazil ice forms the so-called sludge ice, i.e., accumulation of loose, porridge-like, grayish, soaked ice. B. Dybovsky, who observed such soft and plastic ice on the lake, wrote that “our Mazurs (Polish exiles) called it “ice oil”.

Frazil ice, sailing downstream heaps into large, whitish lumps, and reaches river parts where ice is onset already. More frazil ice casts up on the edge of the ice; it accumulates there and gradually drags down under the ice cover surface. The farzil ice clogs the river channel under the ice, the current slows down and eventually the entire cross-section of the channel is blocked. The so-called ice jam forms. The river flow ceases. Below the ice jam the water level begins to fall, and above it the water rises. If the ice jam is solid the water can overflow the banks of the river. A lot of floods in the Irkutsk Oblast on such rivers as the Irkut, Kitoy, and White come like this.

The dam built above Irkutsk saved its residents from misfortunes caused by the upheavals of frazil ice. But not long ago such events were the curse for its citizens. B. S. Dybovsky describes one of them that happened in 1869: “water overflows the dam from under the bottom, often far from the Angara bank; there it rises abruptly until it reaches the level of water flowing between the river banks. In such a way the water percolates through the coarse gravel soil that the city stands on. In the year mentioned above the water used to push out floors from basements, it burst into flats from under the floor, gushed forth from the wells, flooded the yards and the entire neighborhood of the city; and it did not look like the river water. Spilt over basements or houses, cellars, stables, yards and streets the water froze quickly, outdoors it froze almost immediately. Because of this freezing it was hard to escape, and the rescue operations were also complicated.

Just imagine how many people were alienated from the world and confined in the lodgings, bound by the ice that was suddenly formed in the inner porches or in the yards and barricaded the doors! The horses and cattle in stables and sheds, the yard chained up dogs froze ice-bound.

The accumulation of frazil ice often take place on Lake Baikal during its onset period when winds make the frazil ice clog the space between the formed ice near the bank and the bottom of the lake. This impedes ice fishing very much, as fishermen have to drag huge masses of frazil ice out of wells with the help of a special device in the form of a scoop with a wire weaved or simply tin perforated bottom. This small scoop is called sachok (the Russian word meaning “landing or butterfly net”), hence this operation is referred to as taking out frazil ice.

The Irkutsk Reservoir and the rise of Lake Baikal surface for about one meter aggravated the problem of marshy places and ice crust in many lowland rivers and streams. And it was not the problem that the risen lake flooded lowlands on its shores. This process was accompanied by another phenomenon. Many watercourses, rapidly flowing into the lake, are mountain rivers, but at their mouths they flow across the plain. There their water surface slope decreases, the current velocity slows down. The rise of the Baikal level distroyed the natural flow of rivers in lowlands: the water surface slope decreased, and so decreased their pollution assimilative capacity. And conversely, the speed of ice onset increased. Autumn and early winter are such periods when power men seek to rise the level of the Irkutsk Sea (and therefore that of the lake) to maximum in order to stock up water resources for cases of emergency when there is lack of rain water and iced groundwater to replenish reservoirs. Mountain rivers losing their velocity in lowlands, retain its temperature above zero for a long time, and their water spilt over the frozen ground forming a huge ice-crust territory. And in spring this ice-crust becomes the source of flooding that is accompanied by deteriorating of living conditions, loss of homestead lands, pastures and haymaking lands, soil fertility reduction and other attendant phenomena.

It is well known that a number of puzzles and mysteries of ice are not yet explained. Maybe, if a man could be frozen into ice and explore it from inside, he would get more information. But this is not possible yet, and people encounter unexplained phenomena. And the famous Baikal explorer S. Volkov together with his friends encountered one of such mysteries for the first time in his life: “This year (2009 – A. K.) on January 25 on the smooth shiny surface of young black ice in the Peschannaya Bay we saw unusual natural formations frozen into the ice. Star-shaped structures with 6 – 7 opened wide tentacles of the size of a male palm; they had a strange and attractive appearance like in science fiction movies, as if they were growing embryos of future living organisms that got into the ice from the space. On my return to Irkutsk I showed the pictures of frozen “jellyfish” to ice connoisseurs and the scientists from the Limnological Institute of Siberian Branch of Russian Academy of Science. To my great surprise the question how these organisms could get into the ice made scientists buffled, no one could explain what it was. More over, it turned out that those specialists who studied the Baikal ice had never seen anything like that before and to determine the nature of the anomaly they needed the coordinates of the place where they were found and cut out samples of the ice for research. As the scientists concluded the radiant dendrite structure of the ice surface was possible but there was no unambiguous explanation of how it was formed...” (“Argument and Facts in Eastern Siberia”, 18.02.2009). Well, making itself more mysterious even in our scientific and full of information йpoque appears to be the the nature of Lake Baikal.

See also

Literature

  1. A.D. Karnyshev "The Many Faces of Multilingual and Mysterious Baikal"© BSU Publishing House, 2011

Выходные данные материала:

Жанр материала: English | Автор(ы): Karnyshev A.D. | Источник(и): The Many Faces of Multilingual and Mysterious Baikal. Ulan-Ude. 2012 | Дата публикации оригинала (хрестоматии): 2011 | Дата последней редакции в Иркипедии: 30 марта 2015

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Тематический указатель: Irkipedia English