Theos-Talk Archives (January 2006 Message tt00241)

From:
http://www.esa.int/esaEO/SEMIZRMZCIE_index_0.html

Winter snow blankets the heights of the Pamir 
Mountains and the Hindu Kush in this Envisat 
image acquired over Central Asia, the snow cover 
extending to surrounding desert lowlands.

The image covers a jigsaw of national territories 
including western Pakistan, Afghanistan, eastern 
Iran, Turkmenistan, Uzbekistan and Tajikistan. 
This region is well known for harsh winters.

The snow-covered Hindu Kush covers much of the 
image, the western section of an extended 
mountain range system that encompasses the Pamir 
and Karakorum Mountains and the Himalayas. The 
average altitude of the Hindu Kush is 4500 metres.

The overall Hindu Kush-Himalaya system includes 
the highest elevations on Earth and makes up the 
greatest concentration of ice and snow outside 
the Polar Regions. Many major rivers flow from 
it, with the system estimated to supply water for 
500 million people across the region.

Prominent to the south is the yellow expanse of 
Afghanistan's Rigestan desert plateau, with 
rippled sand dunes visible on its eastern side. 
On the western side can be seen the Helmand River 
as it flows south from the Hindu Kush.

The Helmand intermittently flows into marshland 
connected to the greenish lakes seen on the 
western edge of the image, near the city of Z bol 
just over the border with Iran. The Afghan city 
of Kandahar is located on the northern extremity of Rigestan.

Further north can be seen a longer water course 
running down from the Hindu Kush: known to the 
ancient Greeks as the Oxus River, this river 
flows for 2400 km across the arid region.

Its course can be seen about two thirds of the 
way up the image, initially running west where it 
demarcates the border between Afghanistan and 
Tajikistan – today known as the Panj – before 
turning to the northwest to trace the border 
between Turkmenistan and Uzbekistan – where its 
title changes to the Amu Darya.

The Amu Darya once ran all the way west into a 
delta connected to the Aral Sea, but today 
extensive diversion of its waters for irrigation 
means that it runs dry in the intervening desert.

Further north can be seen a dark, elongated water 
body, its southern side dusted with snow. This is 
the human-made Lake Aydarkul in southeast 
Uzbekistan. It has a length of 140 km.

Lake Aydarkul was formed during Soviet times by 
water from Kazahstan's Chardara dam across the 
Syr Darya River being diverted into a natural 
feature called the Arnassay Depression.

The Syr Darya River flows northwest towards the 
Aral Sea (part of its course through snow-dusted 
plains can be seen by clicking to see the full, 
high-resolution image) although like the Amu 
Darya River further south it nowadays dries up long before reaching it.

This is part of an image acquired on 5 January 
2006 by Envisat's Medium Resolution Imaging 
Spectrometer (MERIS) working in Reduced 
Resolution mode. It has a spatial resolution of 
1200 m and a width of 1345 km.

Winter snow blankets the heights of the Pamir 
Mountains and the Hindu Kush in this Envisat 
image acquired over Central Asia, the snow cover 
extending to surrounding desert lowlands.

Full story:
http://www.esa.int/esaEO/SEMIZRMZCIE_index_0.html


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