Transantarctic Mountains

Long ago, the ground next to these mountains began to stretch and pull apart.

At the edge, the land rose up into these mountains.

Scientists explain that forces inside the Antarctic Plate stretched Earth's crust and opened the West Antarctic rift system. Along its edge, the Transantarctic Mountains were lifted up.

A US Geological Survey (USGS) study interpreted the mountains as rising since about 60 million years ago, in bursts rather than at a steady pace.

A USGS report (Demyanick and Wilson, 2007) says the modern range formed as a rift-flank uplift on the margin of the West Antarctic rift system, due to extensional forces acting on the Antarctic Plate in Mesozoic and Cenozoic times. It interprets the range as a series of tilted blocks bounded by faults; in the sector it studied, between the Royal Society Range and the Churchill Mountains, the boundaries between blocks coincide with major outlet glaciers.

A 1991 USGS study by Behrendt and Cooper interpreted the range as rising since about 60 million years ago at episodic rates of about 1 km per million years, most recently since the mid-Pliocene, rather than continuously at a mean rate of 100 m per million years.

Most of Antarctica is under ice, but some valleys in these mountains have no ice cover.

They are very dry and very cold.

Less than 2% of Antarctica is free of ice. The largest ice-free area is the McMurdo Dry Valleys, inside the Transantarctic Mountains. The mountains act as a barrier that holds back ice flowing from the polar plateau.

The valleys have been mostly free of ice for about 4 million years and get less than 10 centimeters of precipitation a year.

A Long Term Ecological Research (LTER) network overview notes that less than 2% of Antarctica is ice-free and that the McMurdo Dry Valleys, located within the Transantarctic Mountains, are the largest such region. The mountains act as barriers to ice flowing from the polar plateau, and the valleys have been predominantly ice-free for the past 4 million years.

With precipitation below 10 cm a year, the overview calls them the most arid, coldest deserts on Earth. In the short summer, alpine glaciers release meltwater that flows in streams into closed-basin lakes.

No trees or bushes grow here.

Tiny living things hide inside rocks and in the soil.

The dry valleys have no flowering plants and no vertebrate animals, and very few insects. Life there is often hard to see with the naked eye.

Some lichens live just under the surface of sandstone rocks. In damp spots near glaciers, mosses, algae and tiny animals such as nematodes, rotifers and tardigrades live in the soil.

The LTER overview describes soils lacking vascular plants and vertebrates, with very few insects, and simplified communities of microinvertebrates, algae and microbes. Cryptoendolithic lichens, a partnership of fungi and green algae growing between the crystals of the rock, are the main organisms living just under the surface of sandstone; lichens on rock surfaces are very rare.

In moist areas near glaciers, mosses, algae, protozoa, rotifers, tardigrades, nematodes, yeasts, fungi, bacteria, mites and springtails are found. Eleven nematode species in 6 genera had been described from the Antarctic by 1979, and a 1991 study found 34% of sampled soils lacked nematodes.

Antarctica is very cold. In the cold, wear warm layers and stay dry.

Wet clothes and wind make you cold faster.

The US Centers for Disease Control and Prevention (CDC) says the most important thing in cold places is to stay dry by wearing layers and quickly changing out of damp clothing.

The CDC explains that the body loses heat fastest through water and wet clothing, then through wind. It suggests a base layer that wicks moisture away from the skin, an insulating middle layer and a hooded, windproof and waterproof outer shell.

The CDC Yellow Book lists the main ways the body loses heat, in descending order of cooling rate: conduction (water immersion, wet clothing), convection (wind) and radiation. In cold environments the most important step is to remain dry by layering and quickly changing moist clothing.

Its sample layering is a moisture-wicking base layer, an insulating middle layer (fleece, down or microfiber) and a hooded, waterproof, breathable, windproof shell. Mild hypothermia begins when the body's core temperature falls to 35°C (95°F) or lower.