The Aral Sea free essay sample

Disaster of Aral Sea The Aral Sea was once the fourth largest inland sea in the world. About, a million years ago from now the northwestern part of Uzbekistan and southern Kazakhstan were covered by a massive inland sea. This sea was formed when all the waters retreated from a big land; they left a broad plain that contained highly saline soil. Due to the retreating of water many ancient remains were disappeared. The only remnant that remained was a big inland sea which was the Aral Sea. The Aral Sea was an inland salt water sea, one odd thing about this sea is, there was no channels connected to the sea.There were two different rivers that feed into the Aral Sea which are the Amu Darya River that flows down from Pamir Mountain and the other one is Syr Parya that flows from Tian Shan Mountains. The fresh water from these two rivers keeps the water of Aral Sea and the slat levels in perfect balance. The first one who pulled the trigger that started the disaster of Aral Sea was the soviet central government. In 1960 decided to make the Soviet Union to be self-sufficient in cotton and to increase the production of rice.To carry on with their plan the government of Soviet Union ordered to people to take out additional amount of water needed from the 2 rivers that was currently feeding into the Sea. Maybe that time they couldn’t think of other source to take out water t use, but because of their decision they created a problem in Aral Sea that could never be fixed. Also from that time the people who lived near the Aral Sea that could never be fixed. Also from that time the people who lived near the Aral Sea had to suffer because the fishes and other organic lives started to face a disaster that might not have any solution Dams that were built by the Soviet Union across the 2 rivers for irrigation also had some affect on salinity, notably by reduction of its variability with the season’s smaller lakes within the Aral sea that have stopped being fed by river flow tend to have higher salinity due to evaporation, causing a lot of fish to die. Before the soviet central union government made the decision to put out water from the 2 rivers the actual Aral Sea was a rich source of fish. About 20 species were identified by the biologists from the sea, including sturgeon an d catfish.The town of Muynak, located on the edge of the sea, was a fishing town that attracted a lot of travelers all around the word to its seaside visits. But, as a result of the soviet central government decision, today Muynak is a desert town more than a hundred kilometers from the sea. The only remains in the town are lot of ships that is in a process of rusting and some ancient fish plant. At first they consumed it was a temporary condition and dredged a canal to the retreating shore so boats could continue to sail the sea and still dock at the wharves.But the effluents that did reach the sea were laced with a deadly mix of salt and pesticides from the cotton fields. Fish populations fluctuated and eventually when the canal was 30 km long and the sea continued to move away, the boats were then abandoned to sail on the sea anymore. The drinking water supplies have sea interrupted, and the water is contaminated with pesticides and other agricultural chemicals as well as bacteria and viruses. The farms in the area near use some highly toxic pesticides and other harmful chemicals. For decades, these chemicals have been deposited into the Aral Sea was lost water, the climate has become extreme. Also when the wind blows across the dried up Sea, it carries dust containing toxic chemicals. So, a centuries old way of life has disappeared in decades. The vast area of exposed seabed is laced with pesticides. It’s estimated that 75 million tons of toxic dust and salts are spread across central Asia each year. If the Aral Sea dries up completely, 15 billion tons of salt will be left behind. Evaporation is another cause of pollution in Aral Sea. More and more water is lost which means more and more of oxygen is disappearing also, so the fishes can’t survive so they die and decompose which emits pollutants e. . ) Algae. As more water has been taken from the rivers, the sea’s water level has decreased by over 60%. As a result of all those problems over the five years the sea’s depth has decreased from 30 metres to 12 metres. One of the main causes of the disaster in Aral Sea is significant loss of water. Although, the water level has fluctuated up to a few metres in the past due to natural variability, in the water flow from the rivers, by 1970. The water loss exceeded the limit of natural water level variation that has occurred in the past. The river inflow has been rapidly decreasing since 1960. Net evaporation has also decreased; as a result, there was a net deficit of water to the sea. In the first period of disappearance, water level has dropped by about 21 cm/year. But, in the next decade or so, the speed of water level has increased to 57 cm/year and as the time goes the rate got faster and faster. As the lake loses water, it becomes shallower. The incoming solar radiation for a given square area now has to heat up a smaller volume of water, thus the water temperature at the surface increases faster.This in turn lowers the specific humidity at the surface, which further increases the rate of evaporation. Another factor that accelerated the evaporation is that the Salinization of the lake leads to vertical stratification. (Full of water) (Almost no water) As the sea level dropped because of water, inflow of salts to the sea exceeded the salt discharge. In the salt ten years, the salinity increased by 14%, which exceeded the threshold for many commercial fish. As a result commercial fishing catches fell from 43,000 tons in 1960 to zero in 1980.From 1960 to 2004 in 44 years the surface salinity increased from 10ppt to 92ppt. The steep rise in salinity was loss, the element which alters landscapes the most. When agriculture uses furrow irrigation, soil receives an excessive amount of water from rivers and canals. Water then gets filtered by depositing the salt in the soil. Excess water accumulated in groundwater that remains after filtration raises the water table. Risen groundwater dilutes and moves upward the salt resting in the soil. Water moves upward and salt concentration increases in the surface layers of the soil.The water evaporates during day time, leaving the salt behind as it becomes like a layer of snow on the surface of the ground. The other cause of shrinking of Aral Sea is change in the sea surface temperature. The heat capacity is reduced; therefore it can warm up and cool off faster than before. The change in the sea surface between day and night creates more and more of sea breezes. In a sense, Aral Sea has started to exhibit a monsoon climate, which is characterized by seasonal climate change due to warming and cooling of the sea. The shrinking period was also characterized by less ice covering of the sea.The Aral Sea region experienced significant desertification during the desiccation period. Several factors influenced the desertification, including the decline in the groundwater level. Bu cutting off water supply to a region, the hydrological balance of the area becomes offset as more water leaves the region. Frequent low-water periods contributed to the shortfall of needed resources for vegetation. The decline in the groundwater level in the Amudarya and Syndarya deltas lead to increase in salinity. Due to increase in salinity plants began to die away.The vegetation decreased to 40% and the side effect of the decrease in the protective vegetation stronger winds, which led to dust storms in the area. Six million hectares of agricultural land were destroyed as a result of Salinization and desertification. In 1960 the Aral Sea’s biodiversity was considered low. The water in the sea supported no more than 24 species of fish, over 200 species of free living macro invertebrates, and 180 land animal species. Due to the lowering of water level and the rise of salinity and toxicity none of the fish species survived. Less than 30 macro invertebrates survived and of the land animal that were reliant of the Aral Sea a few dozen remain. With the retreating shores once water locked breeding grounds of many fish species became vulnerable to land predators. Also, with the decreasing volume of animal life in the region more salient species were introduced in an attempt to preserve the 44,000 tones of fish pre anuum. The disaster of Aral Sea has degraded the environment in many different ways. After all the miserable things happened they finally came out with possible solutions to recover the Aral Sea.The possible solutions that they came out with were 1. Improving the quality of irrigation canals 2. Installing desalination plants 3. Charging farmers to use the water from the rivers 4. Using alternative cotton species that require less water 5. Using fewer chemicals on the cotton 6. Moving farming away from cotton 7. Installing dams to fill the Aral Sea 8. Redirecting water from the Volga, Ob and Irtysh rivers. This would restore the Aral Sea to its former size in 20–30 years at a cost of US$30–50 billion 9.Pumping sea water into the Aral Sea from the Caspian Sea via a pipeline, and diluting with freshwater from local catchment areas Not all parts of Aral Sea was possible to recover since the south Aral sea has almost completely dried there isn’t anything to do for them because even they try to recover the south Aral Sea they won’t see any progress. At least they had the North Aral sea to attempt to recover one of the thing that they did is the Kazakh government planned to build Dike Kokaral, a concrete dam separating the two different parts of the Aral Sea.