Earth’s youngest desert is shown in this July MERIS satellite image of the Aral
Sea in Central Asia. Once the fourth largest lake in the world, over the last 40
years the Aral Sea has evaporated back to half its original surface area and a
quarter its initial volume, leaving a 40,000 square kilometre zone of dry
white-coloured salt terrain now called the Aralkum Desert.

As its water level has dropped 13 metres since the 1960s the Sea has actually
split into two — the larger horseshoe-shaped body of water and a smaller almost
unconnected lake a little to its north. This Small Aral Sea is the focus of
international preservation efforts, but the Large Aral Sea has been judged
beyond saving (the shallowness of its eastern section is clear in the image). It
is expected to dry out completely by 2020.

Towards the bottom right can be seen the sands of the Qyzylqum Desert. Already
stretching across an area greater than Italy, this desert is set to extend
further west in future, eventually merging with its younger Aralkum sibling. The
distinctive darker area to the south of the Large Aral Sea is the delta of the
Amu Darya river. Its waters support environmentally-unique tugai forests found
only in Central Asia, along with land used for rice and cotton cultivation.

The grey area seen in the otherwise whitish zone between the two arms of the
Large Aral Sea was once Vozrozhdeniye (‘Rebirth’) Island, the isolated site of
biological warfare experimentation during the Cold War, now joined to the
mainland and freely accessible by foot. In reaction to this development, a
US-led international team last year moved in to destroy remaining anthrax stocks.

Located on the border between Uzbekistan and Kazakhstan, the Aral Sea shows what
happens when the concept of sustainable development is disregarded. Starting in
the 1960s, the waters of the two rivers feeding the Sea — the Amu Darya, seen
south, and the Syr Darya to the northwest — were diverted by Soviet planners to
irrigate thirsty cotton fields across the region. By the 1980s there was little
water reaching the lake and it began to shrink.

For local people the results have been disastrous. The Aral Sea’s retreating
shoreline has left ports landlocked and boats stranded on dry sand. Commercial
fishing was forced to halt twenty years ago. The few remaining fishermen commute
by car to the water’s edge. The waters that remain grow increasingly saline so
only salt-resistant fish imported from elsewhere can endure them. Wildlife
habitats have been destroyed and communities find themselves without clean water

The retreat of the waters has also altered the regional microclimate. Winters
are colder and the summers hotter. Each year violent sandstorms pick up at least
150,000 tonnes of salt and sand from the dried-up lakebed and transport it
across hundreds of kilometres.

The sandstorms are tainted with pesticide residue and have been linked to high
regional rates of respiratory illnesses and certain types of cancer. The salty
dust does harm to livestock pastures and has even been linked with melting
glaciers up in the distant Pamir Mountains, on the Afghanistan border.

Back in the days of the USSR, planners spoke casually of diverting Siberian
rivers to save the Aral Sea. Today that certainly will not happen. Instead
Central Asian governments have come together to establish the International Fund
for Saving the Aral Sea. But their economies are too dependent on cotton exports
to end all irrigation.

The Small Aral Sea is still thought to be saveable, and several dikes have been
constructed to cut it off from the Large Aral Sea — preventing water loss and
salt contamination — but shifting water levels have so far defeated these
efforts. The channel connecting the two should soon dry up anyway, preserving
the Small Aral Sea at least. Meanwhile researchers are studying the salty
Aralkum Desert — effectively the newest land surface on Earth — to see how
best to promote plant growth and stabilise the dusty dry lakebed.

About the picture

The image was acquired on 9 July 2003 by the Medium Resolution Imaging
Spectrometer (MERIS) instrument on board ESA’s Envisat environmental satellite
with a resolution of 300 metres.

Related links

* Envisat Results

* Envisat instruments

* MSF on Aral Sea

* DLR on Aral Sea

* Aralkum Desert


[Image 1:]
This image of the dying Aral Sea was taken by Envisat’s Medium Resolution
Imaging Spectrometer (MERIS) instrument on July 9. The whitish land surrounding
the remaining waters of the evaporating Aral Sea is a salt-covered dry waterbed
known as the Aralkum Desert.

Credits: ESA

[Image 2:]
During its heyday the Aral Sea fishing town of Muynak had fishing boats deliver
their catch straight to canneries that employed 2,000 people. Now the town is
150 km away from water. As local poverty grows and clean water sources dwindle,
Medecins San Frontieres reports that the rate of tuberculosis infection on the
dying shores of the Aral Sea is among the highest in the world.

Credits: Petter Hveem – Medecins San Frontieres Norway

[Image 3:]
This south-facing image of a much larger Aral Sea was taken by an astronaut on
the Space Shuttle Challenger (carrying ESA’s Spacelab) in August 1985. See how
Vozrozhdeniye Island — once the site of biowarfare experiments — was then
still very much cut off from the mainland. Space images have traced the Aral
Sea’s rapid decline during the past two decades, right up to the latest July
2003 MERIS image, in which half the former lakebed is now dry salty desert and
the remaining waters have divided.

Credits: NASA