New research: Is Mount Everest steadily getting taller?
According to an international team of scientists, Mount Everest, the tallest mountain on Earth, could indeed be getting taller. Their research suggests that Everest grows by up to 2 millimetres each year. This gradual increase in height is believed to be influenced by tectonic activity, with the river flowing at the mountain’s base playing a significant role in its uplift.
Mount Everest, the highest peak on Earth, has long been a destination for adventurers seeking glory, but it is also a place of heartbreak and loss. It is estimated that more than 300 climbers have perished on its slopes, their bodies still lying where they fell, having died either during their ascent or while descending. Among the lives claimed by Everest are seven Polish climbers, victims of avalanches and fatal falls.
Despite the dangers, thrill-seekers continue to risk everything to stand atop the world’s highest point. One such adventurer was influencer Patec, who reached the summit on 31 May 2024.
Mount Everest: Still growing?
Interestingly, the Mount Everest of today is taller than when it was first conquered in 1953. Researchers from University College London have found that the peak rises by as much as 2 millimetres each year. This increase is partly attributed to the Arun River, located 75 kilometres from the mountain's base, eroding land in its basin, indirectly contributing to Everest's steady elevation gain.
"It’s a bit like throwing a load of cargo off a ship," study co-author Adam Smith told the BBC. "The ship becomes lighter and so floats a little higher. Similarly, when the crust becomes lighter… it can float a little higher."
Scientists explain that the Arun River, which flows through the Himalayas, plays a key role in Mount Everest’s gradual rise. As the river erodes material from the Earth's crust—specifically its riverbed—it reduces the pressure on the mantle, the layer beneath the crust. This reduction in pressure causes the thinned crust to flex and lift upwards, elevating the peaks resting on it. This phenomenon is known as isostatic rebound.
A study published in Nature Geoscience reveals that this process is not only responsible for lifting Mount Everest but also the fourth and fifth highest peaks in the world, Lhotse and Makalu.
Scientists explain their study
"Mount Everest and its neighbouring peaks are growing because the isostatic rebound is raising them up faster than erosion is wearing them down," fellow co-author of the study, Dr Matthew Fox, told the BBC. "We can see them growing by about two millimetres a year using GPS instruments, and now we have a better understanding of what’s driving it."
Dr Xu Han of China University of Geosciences, lead author of the study, adds: "The changing height of Mount Everest really highlights the dynamic nature of the Earth’s surface. The interaction between the erosion of the Arun river and the upward pressure of the Earth’s mantle gives Mount Everest a boost, pushing it up higher than it would otherwise be."
Some researchers not convinced
Professor Hugh Sinclair of the School of Geosciences at the University of Edinburgh has some doubts about the study by his fellow researchers. The scientist acknowledged that the conclusions of the analysis are promising but that it is difficult to assess the impact of river erosion on the uplift of the Earth's surface. The researcher explained: "Firstly, predicting river incision of such large catchments in response to drainage capture (one river capturing another river or lake) is challenging."
Sinclair added that the distance over which mountains uplift from a point of intensive localised erosion is extremely hard to predict: "However, even accounting for these reservations, the possibility that some of Everest’s exceptional elevation is linked to the river, represents an exciting insight."
The scientists responsible for the study acknowledged that Professor Sinclair's concerns were valid.
Source: BBC
