Category:

• Home
• Salt chambers (0)
• Salt Caves (3)
• Salt grottos (0)
• Salt saunas (0)
• Salt Plates (0)
• Salt Puzzles (0)
• Salt Lamps (0)
• Graduations towers (0)
• Health (11)
• Salt Mine (11)
• Salt (31)

New articles:

• Salt cellars
• World's longest salt cave
• Salt Grottos use - part 3rd
• Salt lakes - Baskunchak
• Salt Grottos use - part 2nd
• Salt lakes - Namtso
• Salt Grottos use - part 1st
• Salt caverns in Ontario
• Salt cave in Israel

Aral Sea - current situation

The Aral sea's surface area has shrunk by approximately 60%, and its volume by 80%. In 1960, the Aral Sea was the world's fourth-largest salt lake, with an area of approximately 68,000 km² and a volume of 1100 km³; by 1998, it had dropped to 28,687 km², and eighth-largest. Over the same time period its salinity has increased from about 10 g/l to about 45 g/l. As of 2004, the Aral Sea's surface area was only 17,160 km², 25% of its original size, and still contracting.
Even the recently discovered inflow of submarine groundwater discharge into the Aral Sea will not in itself be able to stop the desiccation. This inflow of about 4 billion cubic metres per year is larger than previously estimated. This groundwater would originate in the Pamirs and Tian Shan mountains and seek its way through geological layers to a fracture zone at the bottom of the Aral Sea.
In 1987, the continuing shrinkage split the lake into two separate bodies of water, the North Aral Sea (the Lesser Sea, or Small Aral Sea) and the South Aral Sea (the Greater Sea, or Large Aral Sea); an artificial channel was dug to connect them, but that connection was gone by 1999 as the two seas continued to shrink. In 2003, the South Aral further divided into eastern and western basins; the evaporation of the North Aral has since been partially reversed.
Work is being done to restore in part the North Aral Sea. Irrigation works on the Syr Darya have been repaired and improved to increase its water flow, and in October 2003, the Kazakh government announced a plan to build a concrete dam (Dike Kokaral) separating the two halves of the Aral Sea. Work on this dam was completed in August 2005; since then the water level of the North Aral has risen, and its salinity has decreased. As of 2006, some recovery of sea level has been recorded, sooner than expected. "The dam has caused the small Aral's sea level to rise swiftly to 38 m (125 feet), from a low of less than 30 m (98 feet), with 42 m (138 feet) considered the level of viability." Economically significant stocks of fish have returned, and observers who had written off the North Aral Sea as an environmental catastrophe were surprised by unexpected reports that in 2006 its returning waters were already partly reviving the fishing industry and producing catches for export as far as Ukraine. The restoration reportedly gave rise to long absent rain clouds and possible microclimate changes, bringing tentative hope to an agricultural sector swallowed by a regional dustbowl, and some expansion of the shrunken sea. "The sea, which had receded almost 100 km south of the port-city of Aralsk, is now a mere 25 km away." There are plans to build a new canal to reconnect Aralsk with the sea. Construction is scheduled to begin in 2009, by which time it is hoped the distance to be covered will be only 6 km.
The South Aral Sea, which lies largely in poorer Uzbekistan, was largely abandoned to its fate, but the project in the North Aral has brought at least faint glimmers of hope: "In addition to restoring water levels in the Northern Sea, a sluice in the dike is periodically opened, allowing excess water to flow into the largely dried-up Southern Aral Sea." Discussions are underway to possibly recreate a channel between the somewhat improved North and the desiccated South, along with ambitious but uncertain wetland restoration plans throughout the region. As it has dried, the South Aral has left behind vast salt plains, producing dust storms, and making regional winters colder and summers hotter. Attempts to mitigate these effects include planting vegetation in the newly exposed seabed.
As of summer 2003, the South Aral Sea was vanishing faster than predicted. In the deepest parts of the sea, the bottom waters are saltier than the top, and not mixing. Thus, only the top of the sea is heated in the summer, and it evaporates faster than would otherwise be expected. Based on the recent data, the western part of the South Aral Sea is expected to be gone within 15 years; the eastern part could last indefinitely.
The ecosystem of the Aral Sea and the river deltas feeding into it has been nearly destroyed, not least because of the much higher salinity. The receding sea has left huge plains covered with salt and toxic chemicals, which are picked up and carried away by the wind as toxic dust and spread to the surrounding area. The land around the Aral Sea is heavily polluted and the people living in the area are suffering from a lack of fresh water and other health problems, including high rates of certain forms of cancer and lung diseases. Crops in the region are destroyed by salt being deposited onto the land. The town of Moynaq in Uzbekistan had a thriving harbor and fishing industry that employed approximately 60,000 people; now the town lies miles from the shore. Fishing boats lie scattered on the dry land that was once covered by water, many have been there for 20 years. The only significant fishing company left in the area has its fish shipped from the Baltic Sea, thousands of kilometres away.
The tragedy of Aral coast was portrayed in "Psy" ("Dogs"), a motion picture by Dmitriy Svetozarov (USSR, 1989). The film was shot on location in the actual ghost town, showing scenes of abandoned buildings and scattered vessels. More recently, in 1999, German filmmaker Joachim Tschirner has produced the documentary "Der Aralsee" for the channel Arte.
On 9th/10th June 2007 BBC World broadcast a documentary called 'Back From The Brink?' directed by Borna Alikhani that showed some of the changes in the region since the introduction of the Aklak Dam. His prediction is that within ten years Lake Superior in the United States will contain 15% less fresh water than it currently holds.
Source: http://en.wikipedia.org

24.08.2007. 10:23