The Dry Valleys are located on the continent of Antarctica
roughly 60 miles northwest of McMurdo Station
. The valleys are unique on the earth's surface as they have experienced
no appreciable precipitation
for nearly 2,000,000 years.
The Taylor Valley, typical of the dry valleys, is defined by a depression between two mountain ranges with peaks roughly 14,000 feet. The Matterhorn, the Anti-Matterhorn, and the Whats-a-Matterhorn are three of the most dramatic peaks, despite their whimsical names. The ends of the valley are capped by two blue-ice glaciers, the Canada Glacier to the east, and the Taylor Glacier to the west.
The floor of the Taylor Valley contains several perpetually frozen lakes, which are the remains of retreating glaciers. The lakes are liquid under several feet of ice and contain a variety of primitive organisms which are under study by the National Science Foundations LTER,Long Term Ecological Research, program.
The largest of the frozen lakes in the Taylor Valley are Lake Hoare and Lake Bonney.
Despite being surrounded by glaciers, there is little liquid water on the valley floor even in the austral summer months of December and January. The glacial ice sublimates rather than melts, though there are sparsely distributed mosses at the glacier feet that become active during the few days per year liquid water runoff is present.
Humidity in the dry valleys is close to zero year round, and the wind is nearly constant. The temperatures exceed freezing for brief periods between November and January. Hence the paucity of liquid water.
The valley floor is a variety of fine soils and rocks. A spongy, light green soil predates the dinosaurs and is as fine as talc. Heavier soils and gravels are the eroded remains of the granite and dolorite mountain faces. In addition floor is strewn with weathered chunks of feldspar, lava bombs, quartz, and a variety of animal bones.
The primary erosion force is wind, so there are few rounded, stream-weathered stones like one would find hiking a valley elsewhere on the Earth. Boulders ranging from the size of small buildings to human heads are scattered at the feet of the mountain ranges. Some of these wind-weathered, sand blasted, rocks develop depressions, holes, and complex patterns. These are called ventifact rocks.
NASA uses the dry valleys as a testing ground for Mars exploration equipment, as the environment is as close to the martian environment as can be found naturally.
The dry valleys are deemed ecologically sensitive and activities there are heavily regulated by international treaty. USAP participants working in the dry valleys must complete a training course in winter outdoor survival affectionately known as Happy Camper school, as well as a course in dry valley ecology. It is prohibited by treaty for anyone to disturb rock formations, mummies, fossils, and streams from glacier runoff. No detritus of any form can be deposited, including (especially) human waste. All human output from USAP participants is collected and either burned in rocket toilets or returned to the United States in U-barrels.
Travel to the dry valleys is accomplished via a 50-minute helicopter ride from McMurdo Station.