The Driest Place on Earth Is in Antarctica

While we often picture scorching sand dunes when we think of deserts, the most extreme desert on our planet is a frigid, barren expanse in Antarctica. The McMurdo Dry Valleys are a series of valleys that have been locked in a deep freeze for millennia. Their extraordinary dryness is caused by a unique combination of geography and meteorology. The towering Transantarctic Mountains act as a barrier, preventing the flow of glaciers from the East Antarctic Ice Sheet from reaching the valleys. More importantly, powerful katabatic winds, which are dense, cold air masses pulled downhill by gravity, heat up as they descend and evaporate any trace of water, ice, or snow.

This relentless wind scouring has left the valley floors as a stark landscape of gravel and rock, creating an environment unlike almost any other on Earth. The conditions are so hostile and alien that scientists from NASA use the Dry Valleys as a terrestrial analog for Mars. They test rovers and scientific instruments in this extreme cold and dryness to prepare them for the harsh Martian environment. Despite the hostility, life persists in microscopic forms. Hardy microorganisms, known as extremophiles, have been found living within the rocks, shielded from the brutal conditions, giving researchers clues about where and how life might be found on other worlds.