Is Urine Really Melting Everest? What a New Study Says About the Khumbu Glacier

A new study has put a number on something Everest climbers rarely talk about: the heat from their urine. The research, co-authored by Nepal’s Chief Survey Officer Khim Lal Gautam and published in Regional Environmental Change in July, estimates that urine at Everest Base Camp could melt about 154 metric tons of glacier ice in a single spring season. It’s a quirky headline number, but the same study shows it’s a small slice of a much bigger problem.

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Everest Base Camp, the jumping-off point for the world’s highest peak, serves as the primary logistics hub and center of life for the hundreds of climbers headed for Everest’s summit. It also hosts the thousands of trekkers who come to see the Himalayas. All that activity produces a massive amount of human waste, including hot urine. Urine leaves the body at around 98.6°F (37°C), far above the freezing point of water.

Everest has two base camps: one on the northern (Tibet) side and another on the south (Nepal) side. The northern camp sits on a high desert plateau, while the south side sits on the Khumbu Glacier, so activity there directly affects the ice. At high altitudes, climbers and guides drink large amounts of water to avoid dehydration from the dry conditions. During the 2023 season the researchers studied, about 1,600 tents were set up on the south side, and climbers and support staff produced more than 6,000 liters (about 1,600 gallons) of urine per day during the roughly 50-day spring climbing season. While solid waste is usually collected and brought down, climbers typically urinate right onto the snow and ice.

That 154 tons is a small share of the camp’s total heat. The researchers estimated that human activity at base camp could melt about 2,492 metric tons of ice and snow in a season, which makes urine roughly 6% of the total. These are modeled heat equivalents, not measured ice loss.

The main human factor driving that melt is fuel consumption (LPG, kerosene, petrol) for cooking, heating, and electricity generation. Fuel is the dominant local heat source. Burning 824 LPG cylinders, 18,935 liters of kerosene, and 5,130 liters of gasoline produced enough heat to melt about 2,338 metric tons of ice, roughly 94% of the camp’s total.

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Beyond local activity, climate change is the bigger driver, and it poses a massive threat to the Khumbu Glacier. The study found that surface temperatures at base camp climbed about 0.28 °C per year between 1991 and 2023, roughly twice the rate on the neighboring glacier. A 2013 report in Smithsonian Magazine on regional research found the snow line had receded nearly 600 feet over 50 years and glaciers had shrunk 13 percent, while small glaciers shrank about 43 percent.

While both climate change and local human activity have been rapidly melting the Khumbu Glacier, it might not be too late to slow the melt. Nepal’s tourism department floated moving the camp 200 to 400 meters (650 to 1,300 feet) lower in 2022, but the plan stalled in 2023 amid opposition from local leaders. The new study’s authors are now urging a move.

Meanwhile, the rules are tightening. Climbers must now use SPCC-issued poop bags above base camp and bring back at least 8 kg of garbage, with barrels required at base camp itself. Nepal’s Supreme Court also ordered the government to limit climbing permits in 2024, though it has not set a number.

For now, the camp stays on the ice, and the next decision on relocation will show whether Nepal acts on the new numbers.