Monday, March 23, 2015
MEDIA MONDAY / ASSASSINS OF THE ARAL SEA
Once the fourth largest lake in the world, the Aral Sea is near death at the hands of blundering Russian bureaucracy. Posted are two essays (1.) what caused the problem and the ongoing dilemma to climate (2.) what can be done to save the Aral Sea.
1. GUEST BLOG—By Rebecca Lindsey, writer, NASA’s Earth Observatory--In the 1960s, the Soviet Union undertook a major water diversion project on the arid plains of Kazakhstan, Uzbekistan, and Turkmenistan. The region’s two major rivers, fed by snowmelt and precipitation in faraway mountains, were used to transform the desert into farms for cotton and other crops.
Before the project, the Syr Darya and the Amu Darya rivers flowed down from the mountains, cut northwest through the Kyzylkum Desert, and finally pooled together in the lowest part of the basin. The lake they made, the Aral Sea, was once the fourth largest in the world.
Although irrigation made the desert bloom, it devastated the Aral Sea. This series of images from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite documents the changes.
At the start of the series in 2000, the lake was already a fraction of its 1960 extent (black line). The Northern Aral Sea (sometimes called the Small Aral Sea) had separated from the Southern (Large) Aral Sea. The Southern Aral Sea had split into eastern and western lobes that remained tenuously connected at both ends.
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.
Source for this post:
2. BRINGING BACK THE ARAL SEA
From University of Mary Washington Blog: http://umwblogs.org/
GUEST BLOG--The story of the Aral Sea is a very sad one. At one point in history the Aral Sea was a thriving salt lake in the Middle East and is now about three-quarters the size of what it once was. As a result of its decrease in size “the land [left] around the Aral Sea is… heavily polluted, and the people living in the area are suffering from a lack of fresh water, as well as from a number of other health problems” (http://www.aralsea.org/).
The land that once contained the water from the Aral Sea has now become a salt desert that supports little life and the people that used to live in thriving fishing communities have abandoned their homes and had to search for other jobs. It is estimated that if nothing drastic is done to help the Aral Sea it will disappear in a few years causing a negative impact not only locally but also globally.
A map showing the time lapse of the shrinking of the sea since 2000 can be found at http://earthobservatory.nasa.gov/Features/WorldOfChange/aral_sea.php, showing us how fast the sea is currently disappearing.
So far the slow decline of the Aral Sea has led to local climate change in Uzbekistan and Kazhikstan, the two countries that border the Sea. The summers there have grown shorter and hotter while the winters have grown longer and colder leaving the people of the region suffering from hunger and worsened health conditions. So how do we save the people and their shrinking Sea? There are many ways that people have thought of that can fix the problem however, most of them are too expensive for the poor countries that surround the sea to implement.
Currently Uzbekistan, the smaller and poorer of the countries, mainly exports rice to make money for their country, however this crop needs a lot of water. The people have resorted to diverting the rivers for irrigation for their crops and thus taking away about 80% of the resource of water that would have flown into the sea.
If the people could find a crop that used less water, the rivers could once again flow freely into the sea, restoring some of the volume that has been lost. Since the rivers have been diverted the land left behind is now covered in salt and toxic chemicals leaving the soil lacking in nutrients for anything to grow.
Some scientists, luckily, have thought of a slow but sure solution to fix this issue by planting Haloxylon or saksaul as it is know in Russian. This is a tree that grows well in the soil being highly drought resistant, once a path has been cleared of the harsh top layer of soil. When planted in rows the trees create paths for naturally growing “forests” and thus allow for plants and animals that would have otherwise not survived to live there, along with keeping the soil free of salt and chemicals, helping restore the land.
Despite these small efforts by the people, if more is not done for the Aral Sea it will soon be lost causing a disastrous effect on the environment; hopefully people will join together and form a solution to save the sea.