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Climate change is melting the glaciers of the world's highest mountains, affecting millions downstream.
See video as it originally ran at Time.
William Wheeler: For D.P., the trekking guide, the Himalayan mountains of Nepal are a refuge from the modern ills of the city. He relishes time away from the crowds, water shortages, and pollution of the capital, Kathmandu.
Damondon Pyakurel, Trekking Guide: Mountains have very good fresh air. You can see in the background; it's so big. The forest, and the water; enough water. How [ever] much we want. And we can, like, feel extra energy in the mountains.
Wheeler: But he also wants to bring people to these majestic mountain-scapes, to see the clear and present danger of global warming. After an 8-hour drive in a Jeep, D.P. leads us on a three-day trek into the peaks, where he says evidence of climate change is most visible.
Soon into the trek, D.P. points to a chasm of rubble. One of many landslides triggered by the torrential rains of the monsoon.
D.P.: This is quite a big landslide. Every monsoon we have gotten this prevalent in the park.
Wheeler: Scientists expect this kind of extreme weather will only intensify if the planet warms. The trail rises to 14,000 feet.
As we gaze up at the mountain peaks, we see the Kenjan Glacier.
D.P.: When I was first time here, it was seventeen years ago. This here glacier was very down [sic], ten or twenty meters down, you know? But now it's melting every day, and getting higher, higher. And you can see all the glacier; it's called Lang Tang Yu. When I was first time here, I saw the glacier until down here.
Wheeler: Just beneath the glacier, we find the town of Kenjan and a Buddhist monastery. Jhandu Lama remembers how the weather was different when he was a child.
Jhandu Lama: I remember when I was a child, the snow come up right here, you know? But now, last year, like this snow, very few.
Wheeler: Every summer, as the weather grows warmer, the shepherds and their yak leave the Kenjan village and head for higher and cooler altitudes. Two hours up the mountain, we find them celebrating a ritual to welcome the animals back. They ask for good health as they make their way farther up the trail.
Gyal bu Taman, yak herder, tells us that when it's too warm, the grass dries up. So the production of milk goes down. If there's not enough grass, the animals die. Every year, about a hundred yaks die because they don't get enough food, and it's too hot. But Taman doesn't blame greenhouse gases for the problem. He blames us.
The glaciers are receding, because more and more trekkers and people are coming here, he says. That's why it isn't raining, but getting hotter.
What affects a local yak herder at this altitude, can have an even greater impact for those downstream along glacier fed rivers in India, Pakistan and Bangladesh. Less snow and smaller glaciers here in the Himalayas will mean less melting water for the millions who live downstream.
Madav Karki, ICIMOD: Because glaciers melting is highest in the Himalayan mountains compared any other parts in the world, and the glacial melting is actually an indicator of climate change.
Wheeler: Madav Karki directs ICIMOD, an international NGO that focuses on the health of the Himalayas. This year, the organization has designated one glacier in the Long Tung region as a benchmark. They'll monitor its changes and try to predict overall impacts of climate change on the Himalayas, subject about which there is little scientific understanding.
Karki: If this rate goes, by 2050, two-thirds of the glacier will be gone and by 2100, all glaciers will be gone. This means a very huge impact on the rivers like the Ganges, the Indus, the Brahmaputra. In fact, the predictions are that these rivers may turn into seasonal rivers. Which means that billions of people will be impacted
Wheeler: In the Kathmandu valley, the people are already getting a taste of how that might feel. Nepal relies on the seasons for much of its water. When the monsoon comes, it's one of the world's water-rich countries. But in the dry season, people are often parched. Many residents of Kathmandu spend hours each day waiting for water tankers or lining up to take their water from natural springs. This is because the Nepali government has been hobbled by political instability. And there's little infrastructure to store and distribute water. Soon the monsoon will come and leave the pressure on Kathmandu's thirsty residents.
D.P. will have to wait out the monsoon season amid the urban clamor of Kathmandu.
D.P.: Actually, if I said honestly to you, I don't like the Kathmandu. [There's] so much pollution in the air, and you couldn't even get fresh air.
Wheeler: In the fall, the rains will subside, and he will guide another group of trekkers back to the glacial peaks, the source of Kathmandu's water and a warning sign for the rest of the world.