What is the hottest place on Earth? NASA satellite imaging shows that Iran’s Lut Desert is the winner, with its sweltering sandscapes of dunes and wind-carved rocks. The 25th largest desert in the world also holds a few surprises: Even though it is remote and extremely arid, researchers have found life coping with these extreme conditions.
What Is the Hottest Place on Earth, and How Is It Measured?
Imaging data shows the actual heat on the land surface of the Lut Desert as the satellite passes overhead, according to Geoscience and Remote Sensing Letters.
NASA has used MODIS (Moderate Resolution Imaging Spectroradiometer) data collection, which differs from land-based temperature recording in that it relies on remote sensing. Land-based data collection uses specific weather stations placed in physical locations. The stations must not be placed in shade, and the thermometers must be out of the sun. They’re also situated a few feet above the land and measure the surrounding air temperature rather than that of the surface. Temperature recording is affected by air circulation.
However, satellite imaging is not affected by wind or convection currents. It shows how hot it would be to walk across the desert surface, with Lut’s maximum land surface temperature recorded above 80 °C (176 °F) in 2018.
What Makes the Lut Desert So Hot?
There are various factors that make this area such a hot spot. Its geographical location is one; Iran gets only a third of the world’s average amount of annual rainfall.
Another factor is the desert’s appearance. The landscape is described as low albedo land. Its most extreme hot spots are covered with dark rocks, volcanic debris and sand. This makes the surface so dark that it does not reflect the light and therefore absorbs solar energy from the sun. The heat energy then radiates out and the surrounding area gets hotter. This thermal radiance is what the MODIS satellite picks up.
This solar energy absorption is the reverse of the albedo effect seen in the ice fields at the poles, where the brightness of the frozen surface reflects back the sun’s rays, keeping the surrounding air cool and reducing ice melt. This opposite nature earned the Lut Desert its nickname as Earth’s thermal pole.
Life in the Dunes
The Lut Desert is quite remote and almost inaccessible, but researchers have explored some of its vast area, investigating how life adapts under extreme conditions. They discovered both plant and animal life surviving and thriving. Although it’s extremely arid, there are areas where water lies not far from the desert surface.
Plant life is rare, but specialized long-rooted sedges colonize the sand around some of the tallest shifting sand dunes in the world. There are also moths, numerous insects and even some mammals. National Geographic describes how Rüppell’s desert fox copes with the arid conditions by concentrating its urine to reduce water loss. The region may also be home to the critically endangered Asiatic cheetah. There may be fewer than 100 individuals left in the wild.
Researchers also recently identified a previously unknown crustacean, Phallocryptus fahimii sp. n. living in the rare salty marsh areas in the desert. A 2020 Science Daily summary describes how this new creature has adapted to living in seasonal freshwater ponds. It can survive years of drought then hatch once water returns.
How to Live in a Desert
Since the area is so dry and plant life is not particularly abundant, biologists wonder — how do animals survive in what is the hottest place on Earth?
One theory is a little gruesome, but it seems highly probable according to an article in Science Mag. On one expedition, researchers noted numerous bird carcasses stripped bare in the sand. They theorized that migrating birds might get lost and then perish from lack of water in the desert’s steep-walled canyons. Desert dwellers would then use these to supplement a meager diet.
Other desert inhabitants take it a step further. The spider-tailed horned viper has tufts protruding from its tail. When it waves them around, they look very much like a spider. Using this as a lure, the snake brings the exhausted birds closer before striking at them for a meal.
Hotter Days Ahead
Climate change is predicted to make large areas of the Middle East uninhabitable without air conditioning. Already, habitations around the fringes of the desert are pulling back, which further guarantees that the Lut Desert, a UNESCO World Heritage Site, will remain mostly undisturbed. However, this won’t protect its inhabitants from the additional stress of higher daytime temperatures on top of their daily challenges for survival.