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Melting of Himalayan Glaciers Has Doubled in Recent Years

A newly comprehensive study shows that melting of Himalayan glaciers caused by rising temperatures has accelerated dramatically since the start of the 21st century. The analysis, spanning 40 years of satellite observations across India, China, Nepal and Bhutan, indicates that glaciers have been losing the equivalent of more than a vertical foot and half of ice each year since 2000 — double the amount of melting that took place from 1975 to 2000. The study is the latest and perhaps most convincing indication that climate change is eating the Himalayas’ glaciers, potentially threatening water supplies for hundreds of millions of people downstream across much of Asia.

“This is the clearest picture yet of how fast Himalayan glaciers are melting over this time interval, and why,” said lead author Joshua Maurer, a Ph.D. candidate at Columbia University’s Lamont-Doherty Earth Observatory. While not specifically calculated in the study, the glaciers may have lost as much as a quarter of their enormous mass over the last four decades, said Maurer. The study appears this week in the journal Science Advances.

Currently harboring some 600 billion tons of ice, the Himalayas are sometimes called the earth’s “Third Pole.” Many other recent studies have suggested that the glaciers are wasting, including one this year projecting that up to two-thirds of the current ice cover could be gone by 2100. But up to now, observations have been somewhat fragmented, zeroing in on shorter time periods, or only individual glaciers or certain regions. These studies have produced sometimes contradictory results, both regarding the degree of ice loss and the causes. The new study synthesizes data from across the region, stretching from early satellite observations to the present. The synthesis indicates that the melting is consistent in time and space, and that rising temperatures are to blame. Temperatures vary from place to place, but from 2000 to 2016 they have averaged 1 degree Centigrade (1.8 degrees Fahrenheit) higher than those from 1975 to 2000.

Oblique view of the Himalayas on the border of Sikkim, India and eastern Nepal, captured Dec. 20, 1975 by a KH-9 HEXAGON spy satellite. Such declassified images were used by researchers in a new study of Himalayan glaciers. (National Reconnaissance Office/U.S. Geological Survey)

Maurer and his colleagues analyzed repeat satellite images of some 650 glaciers spanning 2,000 kilometers from west to east. Many of the 20th-century observations came from recently declassified photographic images taken by U.S. spy satellites. The researchers created an automated system to turn these into 3D models that could show the changing elevations of glaciers over time. They then compared these images with post-2000 optical data from more sophisticated satellites, which more directly convey elevation changes.

They found that from 1975 to 2000, glaciers across the region lost an average of about 0.25 meters (10 inches) of ice each year in the face of slight warming. Following a more pronounced warming trend starting in the 1990s, starting in 2000 the loss accelerated to about half a meter (20 inches) annually. Recent yearly losses have averaged about 8 billion tons of water, or the equivalent 3.2 million Olympic-size swimming pools, says Maurer. Most individual glaciers are not wasting uniformly over their entire surfaces, he noted; melting has been concentrated mainly at lower elevations, where some ice surfaces are losing as much as 5 meters (16 feet) a year.

Some researchers have argued that factors other than temperature are affecting the glaciers. These include changes in precipitation, which seems to be declining in some areas (which would tend to reduce the ice), but increasing in others (which would tend to build it). Another factor: Asian nations are burning ever-greater loads of fossil fuels and biomass, sending soot into the sky. Much of it eventually lands on snowy glacier surfaces, where it absorbs solar energy and hastens melting. Maurer agrees that both soot and precipitation are factors, but due to the region’s huge size and extreme topography, the effects are highly variable from place to place. Overall, he says, temperature is the overarching force. To confirm this, he and his colleagues compiled temperature data during the study period from ground stations and then calculated the amount of melting that observed temperature increases would be expected to produce. They then compared those figures with what actually happened. They matched. “It looks just like what we would expect if warming were the dominant driver of ice loss,” he said.

Changri Nup Glacier, one of the hundreds studied by the researchers. Much of it is covered by rocky debris. The peak of Mt. Everest is in the background at left. (Joshua Maurer)

Ice loss in the Himalayas resembles the far more closely studied European Alps, where temperatures started going up somewhat earlier, in the 1980s. Glaciers there started wasting shortly after that increase, and rapid loss of ice has continued since then. The Himalayas are generally not melting as fast as the Alps, but the general progression is similar, say the researchers. The study does not include the huge adjoining ranges of high-mountain Asia such as the Pamir, Hindu Kush or Tian Shan, but other studies suggest similar melting is underway there as well.

Some 800 million people depend in part on seasonal runoff from Himalayan glaciers for irrigation, hydropower and drinking water. The accelerated melting appears so far to be swelling runoff during warm seasons, but scientists project that this will taper off within decades as the glaciers lose mass. This, they say, will eventually lead to water shortages. A separate study published this May estimates that yearly runoff is now about 1.6 times greater than if the glaciers were replenished at the same rate they were melting. As a result, in many high-mountain drainages, meltwater lakes are building rapidly behind natural dams of rocky debris; these are threatening downstream communities with potentially destructive and deadly outburst floods. Even on Mount Everest, long-lost corpses of climbers who failed to return are emerging from melting  ice and snow along trails.

The study shows that “even glaciers in the highest mountains of the world are responding to global air temperature increases driven by the combustion of fossil fuels,” said Joseph Shea, a glacial geographer at the University of Northern British Columbia who was not involved in the study. “In the long term, this will lead to changes in the timing and magnitude of streamflow in a heavily populated region.”

“It shows how endangered [the Himalayas] are if climate change continues at the same pace in the coming decades,” said Etienne Berthier, a glaciologist at France’s Laboratory for Studies in Geophysics and Spatial Oceanography, who also was not involved in the study.

The study was coauthored by Joerg Schaefer and Alison Corley of Lamont-Doherty Earth Observatory, and Summer Rupper of the University of Utah.

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Shreeram Thapaliya
3 years ago

Yes, it is melting very rapidly, I have been a mountain guide for 13 years and I have observed many things which are about Climate change. The Glaciers are losing their volumes and tree lines are moving into the higher elevations. Talking about the Khumbu Glaciers which comes from the Mt.Everest is one of the glaciers which is melting so quickly and you can see water at a 6000-meter level too. Likewise, in Annapurna, the Glaciers are shrinking so the trees are growing their where it was a glacier before 40 years ago. ICCIMOD has recently published the article about the Glaciers melting on a topic of Global Warming Could Melt At Least A Third Of Himalayan Glaciers. You can find here the report. https://www.npr.org/sections/goatsandsoda/2019/02/05/691578203/report-global-warming-could-melt-at-least-a-third-of-himalayan-glaciers This is sad for a Human being and environment.

Shreema Shrestha
2 years ago

It’s very informative news. Global Warming and its effect is a contemporary burning issue in the world. It’s affect in the Himalayan zone is huge. As the mountain guide in Nepal I have also been experiencing the changes caused by Global warming in Himalayas for more than a decade. The snows are the melting quickly, new glacial lakes are appearing which we could not see in the past. I think the concerned authority should address this problem soon and take initiative to minimize it. Otherwise, it brings a great problem in the environment. 

Last edited 2 years ago by Shreema Shrestha
Jason Dhs
Jason Dhs
2 years ago

The melting has doubled because of the increase in global temperatures. The glaciers and snow blocks we used to see in our childhood have completely disappeared. We also notice a little change in the largest glaciers, the Ngozumpa glacier, and the Khumbu glacier, along the Everest trekking route. Seriously, global warming is a great threat to the Himalayas. If it is not addressed early, it will be too late.

Ram
Ram
1 year ago

Do you know glaciers are large bodies of ice that can be formed high in the mountains? As global warming increases, glaciers melt faster and faster from the bottom, reducing their mass. It also shortens the glacier.
To reduce the effect we humans need to act on it by planting trees, and recycling half of our household waste, and powering our homes with renewable energy.
Do you know:1,200 pounds of carbon dioxide can be saved if you reduce your garbage by 10%

Chirst M
Chirst M
11 months ago

The rise in global temperatures has resulted in a twofold acceleration in the rate of melting. The glaciers and chunks of snow that once marked our younger days are now entirely gone. Notable changes are visible even in the largest glaciers, including the Ngozumpa and the Khumbu, both key features of the Everest base camp trekking area. Truly, the Himalayas are under severe threat from global warming. It’s crucial to confront this issue promptly; delay might lead to irreversible consequences.

Sukute Beach
Reply to  Chirst M
11 months ago

You make a compelling case about the threats of climate change and melting glaciers in the Himalayas. Here are some key points to consider:

1. Glacial melt is accelerating rapidly due to rising global temperatures. The pace of melting has increased from just a few feet per year decades ago to about 100 feet per year now. This is unsustainable.

2. The Himalayan glaciers supply water to major rivers like the Ganges and Indus that over 1.3 billion people depend on for drinking water, agriculture, and hydropower. As glaciers shrink, these water sources become unstable.

3. Glacial melt also contributes to rising sea levels and threatens coastal communities around the world, including in South Asia.

4. Loss of glaciers has negative ecological impacts on the Himalayan region by altering habitats, ecosystems, and the region’s biodiversity.

5. Many Himalayan glaciers could disappear entirely by the end of this century if drastic climate action is not taken soon to reduce greenhouse gas emissions and global temperature rise. This would be catastrophic.

6. Himalayan glaciers are considered the “third pole” due to the sheer volume of ice they contain. Their decline is a stark indicator of how serious climate change has become.

In summary, you’re right that we must act urgently to mitigate climate change through measures to transition to renewable energy, improve sustainability, and reduce emissions. Delay means allowing this important region and the people who depend on it to suffer irreversible damage. International cooperation and commitment will be needed to effectively address this issue.

Balaram Thapa
Balaram Thapa
4 months ago

The doubling rate of Himalayan glacier melt as highlighted in this article underscores a critical environmental crisis, emphasizing the urgent need for global climate action. It serves as a stark reminder of the tangible impacts of climate change on water security and ecosystems. This research underlines the necessity for immediate and collective efforts to mitigate these changes, reinforcing the importance of sustainability and conservation practices for future generations.

Best Regards
Nepal Hiking Team

Shobitaneupane
Shobitaneupane
3 months ago

We have seen the Everest and nearby mountains go snowless in some months. The glaciers are literally filling up and on the verge of bursting. This bursting might affect 100s of villagers in the mountains of Nepal. So, when will this be a global issue?

Pradeep Guragain
Pradeep Guragain
1 month ago

As a seasoned Everest guide, the mountain’s transformation due to climate change is deeply personal. Even from the vantage point of a helicopter flying over Everest Base Camp, the evidence is undeniable. Over the years, I’ve witnessed firsthand the alarming retreat of glaciers, the destabilization of icefalls, and the increased risk of avalanches. The once-familiar landscape is changing at an unprecedented pace, making each expedition more unpredictable and challenging. It’s a stark reminder of the urgency of addressing climate change, not just for the preservation of this iconic peak, but for the future of our planet.