McMurdo Dry Valleys
![Map of the [[McMurdo Sound](https://upload.wikimedia.org/wikipedia/commons/9/9f/Mcmurdo_sound_USGS_map.jpg)
The
McMurdo Dry Valleys are a row of largely
snow-free valleys in
Antarctica, located within
Victoria Land west of
McMurdo Sound. The Dry Valleys experience extremely low
humidity and surrounding mountains prevent the flow of ice from nearby
glaciers. The rocks here are
granites and
gneisses, and glacial
tills dot this
bedrock landscape, with loose gravel covering the ground. It is one of the driest places on Earth and is sometimes claimed to have not seen rain in nearly two million years, though this is highly unlikely and several anecdotal accounts of rainfall within the Dry Valleys exist.
The region is one of the world's most extreme
deserts, and includes many features including
Lake Vida, a saline lake, and the
Onyx River, a meltwater stream and Antarctica's longest
river. Although no living organisms have been found in the
permafrost here,
endolithic photosynthetic bacteria have been found living in the relatively moist interior of rocks, and
anaerobic bacteria, with a metabolism based on iron and sulfur, live under the
Taylor Glacier.
The valleys are located within the McMurdo Valleys
Antarctic Specially Managed Area (ASMA-2).
Provided by Wikipedia