Which Is the Driest Desert in the World?

The Atacama desert is known as the driest desert in the world. The Atacama desert is located in Chile, South America covering up to 1000 km strip of land, the desert continues to the border of Peru. The Atacama desert occupies 105,000 sq.km and if the lower slopes of the Andes are included it occupies up to 128,000 sq.km. The Atacama desert is the world’s driest desert as well as the oldest desert in the world. The desert is mostly composed of stony terrain, salt lakes, and felsic lava. It has experienced the semi-arid condition for the past 150 million years.

Why Is It Called the World’s Driest Desert?

The Atacama desert is known as the driest desert in the world because the desert is tucked in the rain shadow region created by the Andes mountain and the Pacific ocean. The Andes mountain blocks the rainfall to the desert and the atmospheric condition created by the Pacific ocean blocks the evaporation of seawater and prevents the formation of clouds. So, the average rainfall in the Atacama desert is appx. 15 mm per year, but some of the locations in the Atacama receive about 1 to 3 mm per year whereas some areas are noted to have received no rain for more than 500 years.

Life on Mars!

The Atacama desert is often compared to Mars. NASA took the same technology to the World’s driest desert, the Atacama and got the same reading as Mars. Both have the most similar environment. The Atacama is so dry and inhospitable that the Viking Rover detected no life on Mars. But NASA scientists have found photosynthetic bacteria below the interior surface of rocks. So it seems life here is possible, so scientists are researching the Atacama to fulfill the mission of life on Mars. 

The Surprise Rainfall

The driest desert on earth got two deadly rainfalls in 2015 and 2017. Studies show the possibility of at least sixteen microbial species deep inside the soil, using nitrates as food. But after the Atacama storm, things got rough, they discovered that about 12 microbial species had vanished in the ground. About 87% of the bacteria in the lagoons died due to the sudden rainfall that caused “osmotic shock” in organisms, which occurs when single-celled organisms absorb too much water and burst like balloons.