Located in northern Chile, the Atacama Desert is not just an arid region. It covers more than 600 miles (965 km) along the Pacific coast of South America and is one of the most extreme landscapes in the world. Thanks to certain oceanic conditions, there are areas where no rainfall has occurred in recorded history, making the Atacama Desert the most common driest place on earth.
Let’s take a closer look at the geography and climate of the Atacama to better understand why the Chilean desert is so dry and what else makes it unique.
The geography of the Chilean desert
The Atacama Desert, also known in Spanish as Desierto de Atacama, is located between the Pacific Ocean to the west and the Andes Mountains to the east. The northern border touches the south of Peru, while the southern side extends into Chile, towards the port city of Antofagasta.
Within this expanse lie several distinctive features, including the Atacama Salt Flat, the Pampa del Tamarugal (Tamarugal Plateau) and two famous dry valleys near the town of San Pedro de Atacama: Valle de la Luna (Valley of the Moon) and Valle de Marte (Mars Valley).
People compare the Atacama to Mars because the red planet’s surface has a similar climate and terrain. Another common name for Mars Valley is Valle de la Muerte, or Valley of Death.
The desert floor of the Atacama is characterized by arid, alien landscapes, with vast sandy and rocky terrains. Unlike other deserts that occasionally contain oases or scattered vegetation, the Atacama Desert is mainly characterized by how stark and desolate it is.
The altitude varies throughout the region. For example, San Pedro de Atacama is approximately 2,438 meters above sea level, but some higher areas exceed 4,877 meters.
Climate of the Atacama Desert
The Atacama Desert is characterized by its extreme aridity. The combination of cold air from the Peru Current (also known as the Humboldt Current) in the Pacific Ocean and the hot desert air creates a unique weather pattern. The cold sea currents cool the air, causing it to lose its moisture. This dry air then flows over the coastal areas and inland towards the desert.
The Atacama receives almost no water from precipitation, and some parts of the region have not had rain in centuries, making it the absolute driest place on earth.
This lack of precipitation is due to the high elevation of the Andes Mountains, which prevent seaward flowing ice from reaching the desert, and to katabatic winds (high-density air pulled downward by gravity) descending from the mountains, causing the mountains to dry out further. sky.
You might assume that the Atacama Desert would be blisteringly hot because of the extreme drought, but that assumption would be incorrect. The average summer temperature in Antofagasta, a major port city in northern Chile, is a relatively average 65 degrees Fahrenheit (18 degrees Celsius).
Despite its reputation for extreme drought, the Atacama Desert is not whole devoid of moisture.
Along the coast, a phenomenon known as the camanchaca occurs: a dense sea fog from the Pacific Ocean that covers the desert. Although it does not produce rain, the camanchaca does provide a minimal source of moisture for certain plants and animals.
Wildlife and vegetation in the Atacama
Despite the harsh conditions, the Atacama Desert is home to a surprising array of wildlife and plant species.
Along the coast and in the valleys you will find hardy cacti, succulents, flowers and herbs that have adapted to the dry environment. These plants play a crucial role in providing habitat and food for the desert’s animal inhabitants, including foxes, birds, rodents and reptiles.
The desert’s prominent salt flat, Salar de Atacama, is located in the southern part, where unique microorganisms thrive in the salty water. These microorganisms serve as a food source for flamingos, which flock to the country’s largest salt deposit in summer, adding a splash of color to the arid landscape.
Human impact on the Atacama Desert
No matter how inhospitable the Atacama Desert may seem to some, more than 1 million people live there. Throughout its history, the region has faced exploitation of its natural resources, including rich nitrate deposits (also called saltpeter deposits), which companies exploited extensively in the 19th and early 20th centuries.
Mining brought wealth and development to the region, but it also left scars on the landscape and caused conflict between Chile and Bolivia, both of which competed for the area’s natural resources.
Today, the Atacama Desert is still an interesting place for scientists and researchers from all over the world. Its unique conditions make it an ideal location for studying life in extreme environments, while the lack of light pollution or precipitation makes it a perfect place to observe the night sky.
The Atacama is currently home to the Atacama Large Millimeter Array and the Extremely Large Telescope (ELT), and there have been numerous astronomy projects in the region in the past.
5 more incredibly dry places on Earth
The Atacama Desert has the distinction of being the driest place on Earth, but there are a number of other places that are similarly (but not as) arid. It should come as no surprise that the driest areas on Earth are typically deserts, where precipitation is extremely scarce.
1. McMurdo Dry Valleys
Although Antarctica’s McMurdo Dry Valleys have a landscape covered in ice and frozen ground, this polar desert also has extremely low humidity and almost no rain. Located west of McMurdo Sound, the area has an average annual temperature of minus 4 degrees Fahrenheit (minus 20 degrees Celsius) and annual total precipitation of just under 6 inches.
McMurdo Sound is known as a base for British explorer Ernest Shackleton, who wintered there while trying to reach the South Pole between 1907 and 1909. His hut still stands.
2. Sahara Desert
Located in North Africa, the Sahara is the largest hot desert in the world, with high temperatures regularly reaching 122 degrees Fahrenheit (50 degrees Celsius) during the hottest months. It extends from the Atlantic Ocean in the west to the Mediterranean Sea in the north and the Red Sea in the east.
The desert receives an average of 3 inches of rain per year, most of which falls between December and March. Despite the extreme climate, approximately 2.5 million people live in the Sahara.
3. Sonoran Desert
The Sonoran is located in southwestern North America and extends across parts of the United States and Mexico. In the area near the lower part of the Colorado River, temperatures can reach 120 degrees Fahrenheit (49 degrees Celsius) in summer, and average rainfall is no more than 3 inches.
The common vegetation there includes various cactus plants, including saguaros, as well as mesquite trees and creosote bushes.
4. Arabian desert
This tropical desert stretches across much of the Arabian Peninsula in the Middle East and is a land of extremes. The region experiences extremely high temperatures, sometimes as intense as 130 degrees Fahrenheit (55 degrees Celsius).
Although annual rainfall can vary between zero and as much as 51 cm, the average rainfall is less than 10.2 cm per year. Dust storms and violent flooding occur periodically, contributing to the harsh conditions.
5. Namib Desert
The Namib in southern Africa is considered one of the oldest deserts in the world and has suffered from extremely dry conditions for millions of years. Located along the west coast of Africa, the area receives very little rainfall, with inland areas receiving perhaps 5 cm per year and coastal areas averaging 1.3 cm per year.
Very few people live there, although you can find elephants, rhinos, lions and other mammals inland.
This article was created using AI technology, then fact-checked and edited by a HowStuffWorks editor.
Original article: The driest place on earth: the Atacama Desert in Chile
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