One-third of Earth's land surface is partially or totally desert. Antarctica is the largest desert in the world. "Sahara" means "desert" in Arabic so the "Sahara Desert" is the "Desert Desert.". It snowed in the Sahara Desert in 1979. Sand from the Sahara is blown by the wind all the way to the Amazon, recharging its minerals. The desert literally fertilizes the rainforest. Rain has never been recorded in parts of Chile's Atacama Desert, the driest place on Earth. There were once camels roaming in the deserts of Arizona. The Sahara desert stretches farther than the distance from New York to Los Angeles. Google hired a camel to create the Street View of a desert. Alaska has a sand desert with dunes over 150 feet (45 m) high. The Lut Desert in Iran is the hottest place on earth. About 46,000 square miles of arable land turn to desert every year due to climate change and practices such as forest clear-cutting. Desertification threatens the livelihoods of more than 1 billion people in 110 countries, the U.N. says. Only about 15% of the Sahara Desert is covered in sand. More than 1 million people live in the Atacama desert, the driest place on earth, extracting water from aquifers and snowmelt streams and raising llamas and alpacas. There is a secret swimming pool in the Mojave Desert that anyone who finds it can use. In six hours, the world's deserts receive more energy from the sun than humans consume in a year. The world record for crossing the Sahara Desert by bicycle was set in 2011 by a British man who made the 1,084-mile journey in 13 days and 5 hours. The Tree of Tenere was considered the most isolated tree on Earth, being the only one for 250 miles in the Sahara Desert, until a drunk driver hit it in 1973. Temperatures in the Namib desert can reach as high as 60°C during the day and below 0°C at night.