As recently as the 1960’s the Aral Sea of Kazakhstan and Uzbekistan was
the fourth-largest inland sea in the world. Since then, its water volume
has dropped by about 80% due to extensive irrigation systems developed
during the Soviet era to produce cotton and other crops. What was once a
single body of water has now separated into several smaller seas. Since
the separation of the Little Aral from the Large Aral in 1987, the
shores of what had once been an island in the middle of the Large Aral
(Vozrozhdeniya Island) have expanded to form a land bridge that almost
completely separates the eastern and western parts of the Large Aral.
These views from the Multi-angle Imaging SpectroRadiometer (MISR)
portray the Little Aral and the eastern Large Aral at the onset of
winter, on December 3, 2002.
A natural-color view from MISR’s nadir camera is shown at top, while the
bottom panel is a 3D stereo anaglyph in which red-band data from the
60-degree forward-viewing camera is combined with green and blue-band
data from the nadir (vertical-viewing) camera. To facilitate stereo
viewing, the images have been rotated so that north is toward the left
and east is toward the top. Viewing the anaglyph in 3D requires the use
of red-blue glasses, with the red filter placed over your left eye.
Information on ordering glasses can be found at
Little Aral Sea is located near the left-hand edge of these images, and
the eastern portion of the Large Aral is below image center.
Of the two major rivers that once fed the Aral Sea, the freshwater
contribution from the Amu Darya River is now negligible. The Syr Darya
River now only feeds the Little Aral. Depletion of the Aral Sea has led
to soil and water salination and agrochemical contamination. The
retreating shoreline leaves the surface encrusted with salt and with
agrochemicals brought in by the rivers. As the Sea’s moderating climatic
influence has diminished, temperature variations in the region have
altered, resulting in colder winters and hotter, drier summers. When
strong westerly winds occur, large quantities of saline dust (and
agrochemical toxins) can travel several hundred kilometers.
In these images, several groups of low cumulus clouds are clustered over
open bodies of water and are identifiable in the stereo view by their
height above the surface. A number of large white streaks extend
eastward toward the Kyzylkum desert. Although their altitude cannot be
ascertained from the nadir image, the stereo anaglyph shows that they
are close to, or at, the surface. Several of these features originate
from the eastern edge of the Large Aral, and may be associated with
windblown snow and/or salt particles carried aloft.
The Multi-angle Imaging SpectroRadiometer observes the daylit Earth
continuously and every 9 days views the entire globe between 82 degrees
north and 82 degrees south latitude. The MISR Browse Image Viewer provides access to
low-resolution true-color versions of these images. These data products were generated
from a portion of the imagery acquired during Terra orbit 15741. The
panels cover an area of about 370 kilometers x 300 kilometers.
Though the Aral Sea has been steadily shrinking over the past decade, this true-color image from August 2010 shows slight growth in the southern sea as water flowed into it from the Amu Darya for the first time since 2008.