Human activity at Mount Everest’s base camp, including the disposal of thousands of litres of urine, may be contributing to the rapid melting of the Khumbu Glacier, with fuel use and urine together linked to the loss of nearly 2,500 tonnes of ice and snow each year, according to a new study.

The findings, reported by the Independent, come from an international team that examined the environmental impact of activities at the Everest Base Camp on the Nepalese side of the mountain. The research has been published in the journal Regional Environmental Change.

During the spring climbing season, thousands of climbers, guides and support workers gather at the camp, which has evolved into a temporary settlement featuring cafes, large-screen televisions, high-speed internet, hot showers and heated tent floors.

Researchers examined energy use at the camp during the 50-day spring climbing season in 2023. Around 1,600 tents consumed 824 canisters of liquefied petroleum gas, 18,935 litres of kerosene and 5,130 litres of petrol for cooking, heating and electricity.

The combined heat generated by fuel use and human urine amounted to an estimated 849,174 megajoules, enough to melt about 2,492 tonnes of ice and snow.

The researchers placed the likely range between 1,964 and 3,020 tonnes, depending on the margin of error. The resulting volume of water would be enough to fill an Olympic-sized swimming pool, around 83 tanker trucks or approximately 16,700 standard bathtubs.

Urine adds to the heat

Human urine emerged as a notable contributor to the heat generated at the camp.

At high altitude, climbers and guides consume large quantities of water to prevent dehydration, producing an estimated 6,000 litres of urine every day.

While solid human waste is collected and transported down the mountain, much of the urine is released directly onto the glacier.

The researchers estimated that urine alone could melt around 154 tonnes of ice during a single climbing season.

Camp warming faster than surrounding glacier

The study also identified a broader warming trend around the base camp.

Using Landsat satellite imagery from 1991 to 2023, researchers found that surface temperatures at the camp had increased by an average of 0.28°C per year — approximately twice the rate recorded across the surrounding Khumbu Glacier.

The research team, which included Kim Lal Gautam, a senior surveyor at Nepal’s Department of Land Management, said the actual human contribution could be even greater.

Their calculations did not account for heat generated by helicopter operations, climbers’ bodies or yaks used to transport supplies and equipment.

The researchers stressed that climate change remains the main cause of glacial melt on Everest. However, they warned that maintaining a large concentration of people on a rapidly retreating glacier year after year may not be sustainable.

“In the long term, relocating the base camp from the glacier to a stable nearby area should be considered,” they said.