An aerial view of the ship graveyard near Muynak over the dried up Aral Sea in Uzbekistan. U.N. Secretary General Ban Ki-moon visited the sea's remains as part of a trip through former Soviet Central Asia. Sunday, April 4, 2010. U.N. Secretary-General Ban Ki-moon says the drying up of the Aral Sea is one of the planet's most shocking disasters and is calling on Central Asian leaders to step up cooperation in solving the environmental problems. - AP Photo/Alexander Zemlianichenko
The Aral Sea, Before the Streams Ran Dry.
It was once the fourth largest lake in the world. Fed primarily by snowmelt and precipitation from faraway mountains, the Aral Sea supported extensive fishing communities and a temperate oasis in a mostly arid region of Kazakhstan and Uzbekistan.
But in the 1950s and 60s, the government of the Soviet Union launched projects that diverted the region’s two major rivers—the Syr Darya and the Amu Darya. The dams, canals, and other water works were built in order to transform the desert into agricultural fields for cotton and other crops. The Aral Sea has been slowly disappearing ever since.
The changes are dramatically documented in a series of images from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite.
By 2000, when this sequence of satellite photos begins, a large portion of the sea had already been drained. Instead of a single large body of water, there were now two smaller ones: the Northern and Southern Aral Seas. The Southern Aral Sea shrunk further into two lobes connected by narrow channels at the top and bottom.
Satellite images from NASA show that over the last 14 years, one of the world's largest inland bodies of water, the Aral Sea in Central Asia, has almost completely dried up and disappeared.
Click image to see yearly details
By 2001, the southern connection had been severed, and the shallower eastern part retreated rapidly over the next several years. Especially large retreats in the eastern lobe of the Southern Sea appear to have occurred between 2005 and 2009, when drought limited and then cut off the flow of the Amu Darya. Water levels then fluctuated annually between 2009 and 2014 in alternately dry and wet years. Dry conditions in 2014 caused the Southern Sea’s eastern lobe to completely dry up for the first time in modern times.
As the lake dried up, fisheries and the communities that depended on them collapsed. The increasingly salty water became polluted with fertilizer and pesticides. 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. Completed in 2005, the dam was basically a death sentence for the southern Aral Sea, which was judged to be beyond saving. All of the water flowing into the desert basin from the Syr Darya now stays in the Northern Aral Sea. Between 2005 and 2006, the water levels in that part of the lake rebounded significantly and very small increases are visible throughout the rest of the time period. The differences in water color are due to changes in sediment.
Sources: NASA, CBS
The Aral Sea, Before the Streams Ran Dry.
It was once the fourth largest lake in the world. Fed primarily by snowmelt and precipitation from faraway mountains, the Aral Sea supported extensive fishing communities and a temperate oasis in a mostly arid region of Kazakhstan and Uzbekistan.
But in the 1950s and 60s, the government of the Soviet Union launched projects that diverted the region’s two major rivers—the Syr Darya and the Amu Darya. The dams, canals, and other water works were built in order to transform the desert into agricultural fields for cotton and other crops. The Aral Sea has been slowly disappearing ever since.
The changes are dramatically documented in a series of images from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite.
By 2000, when this sequence of satellite photos begins, a large portion of the sea had already been drained. Instead of a single large body of water, there were now two smaller ones: the Northern and Southern Aral Seas. The Southern Aral Sea shrunk further into two lobes connected by narrow channels at the top and bottom.
Satellite images from NASA show that over the last 14 years, one of the world's largest inland bodies of water, the Aral Sea in Central Asia, has almost completely dried up and disappeared.
Click image to see yearly details
By 2001, the southern connection had been severed, and the shallower eastern part retreated rapidly over the next several years. Especially large retreats in the eastern lobe of the Southern Sea appear to have occurred between 2005 and 2009, when drought limited and then cut off the flow of the Amu Darya. Water levels then fluctuated annually between 2009 and 2014 in alternately dry and wet years. Dry conditions in 2014 caused the Southern Sea’s eastern lobe to completely dry up for the first time in modern times.
As the lake dried up, fisheries and the communities that depended on them collapsed. The increasingly salty water became polluted with fertilizer and pesticides. 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. Completed in 2005, the dam was basically a death sentence for the southern Aral Sea, which was judged to be beyond saving. All of the water flowing into the desert basin from the Syr Darya now stays in the Northern Aral Sea. Between 2005 and 2006, the water levels in that part of the lake rebounded significantly and very small increases are visible throughout the rest of the time period. The differences in water color are due to changes in sediment.
Sources: NASA, CBS
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