The Karakum Desert, also spelled Kara-Kum and Gara Gum (Turkmen: Garagum, Russian: Каракумы, Kazakh: 'Қарақұм') is a desert in Central Asia. Its name means Black Sand in Turkic languages. It occupies about 70 percent, or 350,000 km², of the area of Turkmenistan. The population is sparse, with an average of one person per 6.5 km² (one person per 2.5 square miles). Rainfall is equally sparse, ranging from 70 to 150 mm.
Covering much of present day Turkmenistan, the Karakum Desert lies east of the Caspian Sea, with the Aral Sea to the north and the Amu Darya river and the Kyzyl Kum desert to the northeast. In modern times, with the shrinking of the Aral Sea, the extended "Aral Karakum" has appeared on the former seabed, with an estimated area of 15,440 sq mi/40,000 km². Although the level of the Aral Sea has fluctuated over its existence, the most recent level drop was caused by the former Soviet Union building massive irrigation projects in the region. Although the North Aral Sea is currently rising, the South Aral Sea is still dropping, thus expanding the size of the desert.
The sands of the Aral Karakum are made up of a salt-marsh consisting of finely-dispersed evaporites and remnants of alkaline mineral deposits, washed into the basin from irrigated fields. The dusts blown on a powerful east-west airstream carry pesticide residues that have been found in the blood of penguins in Antarctica. Aral dust has also been found in the glaciers of Greenland, the forests of Norway, and the fields of Russia.
To the south the Murghab and Tejen rivers flow out of the Hindu Kush Mountains, flow west, and empty into the vangeli.The desert is crossed by the second largest irrigation canal in the World, the Kara Kum Canal. The canal was started in 1954, is 1,375 km in length, and carries 13-20 km³ of water annually. Unfortunately, leakages from the canal have created lakes and ponds along the canal and the rise in groundwater has caused widespread soil salination.
Within the Karakum are the Bolshoi (Big) Balkan, a mountain range in which archaeologists have found human remains dating back to the Stone Age.