All the Earth's accumulation of water called oceans. Plots of land - continents and islands - separated by oceans oceans, seas, straits and inlets. But there their compound in a unit due to the continuous sea currents. Compared with land size of the ocean is huge. Breast imagine, but only one Pacific Ocean occupies as much space as all the land together, and even more. In the northern hemisphere water occupied space in 61 percent of its surface, and 81 percent in the South! And what is the age of the oceans? And think about it, scientists? It is believed that the formation of the oceans is inextricably linked with the geological development of the entire earth's crust as a whole. This means that the continents and oceans were formed simultaneously. Initially, the continents rose slightly above the bottom of the ocean and the future of themselves were shallow depressions of the ocean water that rose up in the form of vapor and cools the earth fell on the rain. Precipitation filled slides. Further deepening of the bottom was under the influence of internal processes of the Earth at the same time rising and drying. There were times when the ocean was advancing on the land, flooded vast areas of water. Then he retreated and left behind salt deposits. At the same time were naked margin. This is due to local uplift and subsidence of the continental crust, as well as the formation and melting of ice in the so-called glacial and interglacial periods. But, as scientists say, never vast expanses of the ocean, which are at a depth of 3-4 thousand meters, have not seen sunlight, and the total amount it has changed little. There is one more moment without interest, on the ocean: the water is salty is estimated that the concentration of salt is 35 grams to 1 kilogram of water. But this average. Because under the influence of strong evaporation the salinity of the ocean can be a bit more, and in areas of abundant rainfall - less. Along the shores of the same, where the mixing of the water of the rivers which flow into the sea or ocean - is even smaller. Whence and in what circumstances the ocean got salt? It is assumed that during formation of the crust and mantle of the ocean, along with water vapor allocated acidic volcanic fumes such as chlorine, fluorine, bromine. The first water on Earth were acidic. This primary water destroyed the newly formed basalt, granite and other crystalline rocks of the crust and extract the alkaline elements - sodium, magnesium, potassium, calcium and others. A chemical reaction in which alkali elements were in connection with chlorine, fluorine, bromine and neutralized with a solution. Over time, intake of acidic volcanic fumes became smaller, and the salts from the rocks of the land continued. And, then, and ocean water is gradually accumulated salt and acquired an alkaline reaction, which is inherent to it now. And where some 500 million years ago, ocean water is stabilized by salt composition and content of the gases in it. But not only salt found in ocean water. It is also present and some are not always matter in solution. Although their number is not large, but the role is enormous. This, above all the elements that support life processes in the ocean. Their so called biogenic. This salt of phosphorus nitrogen compounds of silicon and calcium, some trace elements dissolved in ocean water in very small quantities. Them something and use vegetable organisms to build their body in the process of photosynthesis. All in all ocean water was found until 70 chemical elements. But according to some scholars, there is a possibility that the oceans are present all the chemical elements in our planet's oceans originated life of the planet. Vegetation, which it arose, enriched oxygen atmosphere and make it suitable for animal life. And until now the activities of vegetable organisms in the ocean on the decomposition of water into oxygen and hydrogen are the main source of free oxygen in the atmosphere between the ocean, atmosphere and land is a continuous exchange of substances Ocean is primarily a reservoir of the planet Water evaporates from the ocean surface winds transported to the mainland and falls as Precipitation that irrigate the land fed rivers and underground water ice but it's incredibly hard facts, together with the spray during storms wind picks up and makes the land for the year 300,400 million tons of salt! But at the same time, by land runoff hedgehog Dry brings the ocean to the average of 3 3 million tons of dissolved solids. About half of this amount is deposited on the seabed more than three billion years is the development and existence of life in the ocean. Marine and oceanic organisms continuously absorb necessary for them to life dissolved substances and gases and form of these complex organic compounds. In turn, the marine organisms secrete metabolic products, and moving in the water, sometimes over long distances, leaves everywhere traces of a variety of their livelihood. And after the death turn into organic matter. When connecting them with the dissolved oxygen in water, restoring the original mineral salts. This happens as if "samoudobrenie" Ocean. Marine animals and plants have relatively surprising ability to accumulate in their body, some elements: copper, zinc, vanadium and iron, as well as some others. As a result of the accumulation of these elements in their tissues in the hundreds and thousands times higher than in seawater. Geochemical significance of this phenomenon is very large. Thanks to him for the withering away of organisms, some salt, and many scattered and rare chemical elements fall out of circulation. They sink to the bottom of the oceans and seas, where they form a powerful layers of bottom sediments and become part of the mineral compounds. The chemical composition of precipitation varied. Basically they are a sludge formed by calcareous and siliceous skeletons and shells - the remains of organisms that inhabit the water column. They pave about half of the ocean floor. It should also focus on the content of gases in seawater. After all, in all natural waters contain a variety of gases, mostly nitrogen, oxygen, carbon dioxide. Amount of gas that can dissolve in the sea Yeah, depends on its salinity, hydrostatic pressure and, oddly enough, mainly on the temperature. The greater the degree of salinity and the higher the temperature, the less gas can dissolve the salt water, and vice versa. Sea water by participating in a variety of chemical and biochemical transformations of the substances is in fact more of the ancient "geochemical reactor. He works at the outer fuel - heat and light energy from the Sun and tirelessly, over billions of years converts geochemical and geological our planet. Oceans also play the role of heat storage in the world. About 95 percent of the water mass it has an average temperature 3.8 degrees. This temperature is in the current climatic conditions remained largely unchanged. But the temperature at the ocean surface - varies greatly. For example, in the equatorial zone of water is heated to 25-26 degrees. In the polar regions, the temperature falls below 0 degrees. With depth, water temperature in the ocean is usually reduced. In northern latitudes, the upper layer of the heated water to fall up to the thickness of 10-15 mW ditch, and in the middle - 40-50 meters. But beneath this layer there is a thin layer of a seasonal spike in temperature. This layer is called the thermocline. Below its water is much colder. When the storm agitated and the winter cooling of the transition layer is destroyed. And then the water temperature becomes uniform to a depth of 50 meters, and sometimes even up to 200 meters, depending on the strength of emotion or the degree of cooling. In winter, cooling water starts at the top. Cold water is heavier and denser than warm, so it falls down and mixes with the lower, warmer water. This vertical circulation of sea water enriches its lower layers of oxygen and carbon dioxide absorbed from the air, and rises to the top of the nutritive salts that have accumulated on the ocean bottom in the decomposition of dead organisms. With the change in temperature, thus changing the density of water. Where the temperature jump - there and jump in density. Therefore, in the layer near the thermocline accumulate small animal organisms. In the vertical direction, they can not overcome this barrier. Following the plankton are going well, and fish. Thermocline partly prevents the spread of sound in water. Noise of the propellers of the submarine acoustic instrumentation surface ship is not captured, if it is below the thermocline. And then the submarine can feel safe. Submariners called the thermocline fluid ground, because a boat, sunk in a dense layer of water under the thermocline, stop the engine, lies, chkak at the bottom ", rather, kept it afloat. An interesting phenomenon in the activities of the oceans began to open once the so-called ocean currents. The main reason for their education - to the winds in a particular trade-wind. They are blowing throughout the year in the Atlantic and the Pacific Ocean. So, on both sides of the equator, moving a flood of North and South trade-wind (equatorial) flows. They blow up water to the western outskirts of both oceans. Part of this water is returned to the east in calm equatorial strip in the form of the Equatorial countercurrent. And the other part rests on the threshold of the continents and islands, and turns to the north or south and then east and forms a circular circulation in both the northern and southern hemisphere. To distinguish between warm and cold currents. But it is not always necessary to understand it literally. For example, the temperature of the water flow of Bengal at the Cape of Good Hope is +20 °. But it is a cold current in comparison with the surrounding water. But the Norwegian current (one of the northern branch of the Gulf Stream) with water temperature 4-6 degrees above zero is considered to be warm, because it warms the surrounding beach. Powerful Pacific During the Kuro-Sio (from the Philippine Islands along Japan) and Gulfstream vot coast of Florida in the north-east to Nyufaunlendekoy banks) in the Atlantic Ocean its water differ from the surrounding water color, salinity and temperature. But the continuous stream, as in rivers, streams do not. For example, the Gulf Stream is divided into separate streams. Some of them aside in and form a huge twist, which were then completely separated from the main flow. The intensity of the currents, the volume of water transported vary widely. It is noticeable impact on the weather and especially the behavior of the fish. "Fluctuations of power the Gulf Stream and Kuro-Sio depend on changes in atmospheric circulation, and in particular the trade winds. We can say that the powerful ocean currents - a river in the ocean. But these rivers pulsing and wandering in their liquid and mobile banks. Until recently it was believed that with depth, especially at the very bottom, ocean waters are fixed. But with the improvement of measuring equipment showed that even at the very bottom of the water moves at a speed of several miles a day (one mile is equal to 1 kilometer 852 meter), and the powerful undercurrent differ little from the surface.
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