The driest place in the United States is Death Valley in California, which I recently visited. What is the driest place on Earth?
— Avery Pingree
The driest place on Earth is in Antarctica (which is the Earth’s driest continent), in an area called the Dry Valleys. The Valleys’ extreme dryness is the result of nearby high mountains that block seaward-flowing ice from getting in, and partially the result of katabatic winds that blow down the mountains. Katabatic winds (often attaining speeds in excess of 100 mph) are caused by gravity pulling cold, dense air downward, warming and drying as it goes. The second driest place is the Atacama Desert, stretching 600 miles from Peru’s southern border into northern Chile along the Pacific Coast. No precipitation falls in the Dry Valleys and none for a few years at a time in portions of the Atacama.