In this photo essay, the editor of the Nepali Times describes the dramatic changes underway in the ice and snow of the Himalayan Mountains.
For many tourists trekking to Mount Everest Base Camp, the trip is an adventure of a lifetime. The thin clear air, stark landscape and ice-tipped peaks pierce the inky sky providing Instagram backdrops.
However, what is stunning scenery to tourists is for climate scientists an apocalyptic sight. They see dramatic evidence all around of a rapidly warming atmosphere.
Visitors returning to the Everest region after many years will notice changes in the landscape: large lakes where there were none; glacial ice replaced by ponds, boulders and sand; the snowline moving up the mountains; and glaciers that have receded and shrunk.
All these features are visible from ground level right from the start of the trek in Lukla. The banks of the Bhote Kosi, part of the river system that drains the slopes of the Himalayas in Nepal and Tibet, still bear the scars of a deadly flash flood in 1985 that washed off a long section of the Everest Trail and the hydropower plant in the village of Thame. The flood was caused by an avalanche into the Dig Tso, a glacial lake.
Further up, near the village of Tengboche, the Imja Khola bears signs of another huge glacial lake outburst flood that thundered down the western flank of Ama Dablam in 1977. And below the formidable south face of Lhotse is Imja Tso, a lake 2 kilometers long that has formed and grown in the last 30 years. It does not exist on trekking maps from the 1980s. All these lakes were formed and enlarged as a result of global warming melting the ice.
Imja Tso, a glacial lake, did not exist on trekking maps 30 years ago. Today it is 2 kilometers long and 1 kilometer wide. Credit: Kunda Dixit/Nepali Times |
Green and blue meltpools on the North Ama Dablam Glacier, where the vanishing icefall has exposed the eroded bedrock below. Credit: Kunda Dixit/Nepali Times |
The Lobuje Icefall is now a hanging glacier, having retreated above the cliff. Credit: Kunda Dixit/Nepali Times |
Khumbu Glacier, the world's highest glacier, has retreated as the planet has warmed. Its lower portion is largely covered by debris. Credit: NASA Landsat 8 image by Jesse Allen and Robert Simmon |
The Khumbu Icefall carries debris and ice from the Western Cwm to the Khumbu Glacier, 1,000 meters below. Credit: Kunda Dixit/Nepali Times |
A map shows base camp and how a key climbing route up Mount Everest changed after a deadly avalanche in 2014. Credit: Gregory Leonard, with data by Digital Globe and Mark Fahey/USGS, via NASA |
The velocity of the glacier is about 70 meters per year at Base Camp, and it slows to about 10 meters per year further below. It's zero at the terminus at 4,900 meters. This means the ice is decelerating as it is squeezed, and the pressure is being released by the melting of the ice mass.
Scientists conclude that the Khumbu Glacier is not about to vanish, and the Icefall is not going to turn into a waterfall any time soon. However, the permanent ice catchment of the glacier above 6,000 meters could start to deplete under a worst-case scenario of 5 degrees Celsius warming.
*This photo essay was shot and written by Kunda Dixit, editor and publisher of the Nepali Times, and first appeared in that publication.
Links
- Melting glaciers around Mount Everest may be forming killer lakes
- Climate Change Is Melting Everest
- Warm ice in Mount Everest’s glaciers makes them more sensitive to climate change – new research
- Scientists Have Discovered 'Warm' Ice in The World's Highest Glacier
- Climate change, crowding imperil iconic route to top of Mount Everest
- Going, Going ... Glacier National Park's Iconic Glaciers Are Melting Away
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