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:
http://earthobservatory.nasa.gov/Features/WorldOfChange/aral_sea.php
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.
CLIMATE IMPACT
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.
WHAT IF?
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.
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