Everest is nearly 1,000 feet (304 meters) taller than surrounding Himalayan peaks, leading scientists to wonder why the giant mountain’s neck sticks out further than its neighbors. Now, one team thinks they’ve found the answer: The mountain isn’t just a pile of more rocks; it’s a pile of more rocks. Instead, the land around it is eroding, pushing the mountain upward.
As a result, Mount Everest (also known as Mount Everest or Sagarmatha) is growing as much as 0.08 inches (2 millimeters) per year, according to a study published earlier this week in the journal Nature Geoscience. Additionally, over the past 89,000 years, 29,032 ft (8,849m) tall peaks have sprouted between 50 ft (15m) and 164 ft (50m) high.
With the exception of Everest, the three tallest mountains—K2, Kanchenjunga, and Lhotse—are all about the same height, about 1,000 feet (305 m) lower than the world’s tallest mountain.
“Everest is a remarkable mountain steeped in myth and legend, and it continues to grow,” Adam Smith, a researcher at University College London and co-author of the study, said in a university news release. “Our study shows that as nearby river systems cut deeper, the loss of material caused the mountain to surge further upward.”
How did this happen? Then the east side of the mountain is the Arun River, and the lower reaches join the Kosi River system. Over tens of thousands of years, the Arun has eroded its banks, washing sediment downstream.
“The upper reaches of the Arun River flows eastward, with high altitude and a flat valley. Then, it suddenly turns south and becomes the Kosi River, losing altitude and becoming steeper,” study co-author Dai Jingen, a geoscientist at China University of Geosciences, said in the same paper said the press release. “This unique topography suggests an unstable state, possibly related to Everest’s extreme altitude.”
GPS measurements show that the mountain has risen faster in recent years than its long-term growth trend. The team developed a numerical model to track the growth of the mountains and concluded that about 89,000 years ago—ancient history for us but recent in Earth’s evolution—the Aren River and Koh Xihe Network merged. When this happens, the latter network absorbs more water, increasing the erosion of river banks and accelerating the uplift of mountains.
“Everest and its neighboring peaks are growing because isostatic rebound is lifting them faster than erosion is wearing them down,” Matthew Fox, a geoscientist at University College London and co-author of the paper, said in the same press release. speed. “We can see them growing about two millimeters per year using GPS instruments, and now we have a better understanding of what’s driving it. “
But this pattern is not limited to Everest. Researchers say Mount Lost Peak and Mount Makalu, the fourth and fifth highest peaks in the world, have also experienced uplift. While the rates of ascent are similar for the three peaks, the rate of ascent is probably slightly higher for Mount Malaku because it is closest to the Arun River.
The study is a reminder of how interconnected the Earth’s surface is – even water flowing through the planet’s rivers can change the shape of our most familiar mountaintops.
