Without snow and ice-free valleys are not unusual – unless you are in the polar regions. Although almost all of Antarctica is ice Skuta, on its territory there are three dry valleys. They lie on the mainland of the continent, east of the glacier shelf and are named Ross Taylor Valley, Wright Valley and the Valley of Victoria.
These are the trough in the U-shaped, with steep edges, carved by glaciers that melted long ago.
It took millions of years to ice skul almost the entire surface of Antarctica cover an average thickness of 3 thousand. m.
In the dry valleys of the snow does not fall, however, almost all; annual rainfall is only 25 mm. But when the snow falls, is blown by the dry winds or melts in the sun heated the surrounding rocks.
In the area of each of the valleys, completely devoid of vegetation, there are salt lakes. The biggest of these is Lake Vanda, whose depth exceeds 60 m, and surface Skuta is a 4-meter layer of ice. The water temperature at the bottom of the lake is as high as 25 ° C and maintained through the ice cover, not allowing heat to penetrate into the atmosphere.
The dry valleys of Antarctica Photo Gallery
McMurdo Dry Valleys – the valley on Earth, Victoria, in certain parts of permanently ice-free. They cover approximately 4800 km2 (0.03% of the continent) and is the largest Antarctic oasis. Due to low humidity and lack of significant ice cover, it is a de facto wilderness.
Dry Valleys bottoms are covered with loose gravel material. Despite its name, in the Dry Valleys several streams of fluid coming from melting glaciers and lakes are permanent. Some of them are among the most saline lakes on Earth. There is also a river of Onyx, the longest river in Antarctica.
The dry valleys of Antarctica video