The blowing dust from the exposed lakebed, contaminated with agricultural chemicals, became a public health hazard. The salty dust blew off the lakebed and settled onto fields, degrading the soil. Croplands had to be flushed with larger and larger volumes of river water. The loss of the moderating influence of such a large body of water made winters colder and summers hotter and drier. In a last-ditch effort to save some of the lake, Kazakhstan built a dam between the northern and southern parts of the Aral Sea.
The Kok-Aral dike and dam, finished in , separates the two water bodies and prevents flow out of the North Aral into the lower-elevation South Aral. The dam has led fisheries in the North Aral to rebound, even as it has limited flow into the South Aral.
Between and , water levels in the North Aral rebounded significantly and very small increases are visible throughout the rest of the time period.
Even re-watering those lakes does not compensate for the increased salinity over the years. In , water level was down by 20m, with a total volume of km3 compared to 1,km3 in Most of the changes in climate and landscape in the Aral Sea basin that we are about to explore are at the least indirect products of Human induced changes.
Thus, the difficulty lies as much in understanding the way climate and other natural systems function as in being capable of weighing the potential consequences of our actions before we undertake them. Risk assessment combined with scientific understanding should undercut our actions more efficiently; adding an ethical dimension to the equation remains more than welcome in addition to those more accessible and quantifiable factors, but is too fragile to be the centerpiece on which our decisions rely before we commit to large scale actions which can often, as we are about to see, engender even larger responses from our environment.
The Aral Sea Crisis. It took the Russians two years to explore the entire area. Before the s, the Aral Sea had a maximum depth of 69 meters western shores and a surface area of 68, square kilometers. It has a maximum length of kilometers from north to south and was kilometers wide from west to east.
However, the average depth was less than 16 meters. The northern shore had numerous bays and the eastern shore had a huge river delta Syr Darya bordered by shallow waters.
Amu Darya delta is on the southern shores. In the early s, the Soviet government came up with a plan to make cotton one of its chief exports. As part of the plan, waters from the Syr Darya and the Amu Darya were diverted from flowing into the Aral Sea to irrigate the desert region.
The Soviets converted large tracts of unused land in Uzbekistan, Kazakhstan, and Turkmenistan into farmland and depended on water from the two rivers and their tributaries. By , the Soviet government had diverted close to 60 cubic kilometers of water from going to the Aral Sea.
By the end of the s, the water level reduced by at least 80 cm every year. The disappearance of the Aral Sea did not surprise the Soviets since they expected it to happen at some point. However, not many people were prepared to deal with the environmental consequences that would follow.
The high mineral and salt content has made the water unfit for use by both wildlife and humans and killed off once-abundant marine species, such as a barbell, carps, sturgeon, and roach. The fishing industry that once thrived in the region, employing over 40, people, was virtually destroyed. As soon as the water levels dropped, the health of the people living in the region began deteriorating.
Dust blown from the sea bed contained toxic material, such as fertilizers, salt, and pesticides.
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