Everest Base Camp sits at 5,364 metres, and it does not sit on rock. It sits on the Khumbu glacier, and for one spring season it is a seasonal town: about 1,600 tents strung 1.6 kilometres along the ice and 2,127 people living there for roughly fifty days. Researchers led by the surveyor Khim Lal Gautam asked every expedition operator what they burned. For one season it was 824 cylinders of cooking gas, 18,935 litres of kerosene and 5,130 litres of petrol, spent on heated dining tents, underfloor heating, hot showers, bakeries, espresso, televisions and generators.
Then they converted it. Fuel and urine together come to about 849,174 megajoules across the season, which is enough heat to melt some 2,492 tonnes of ice and snow — an Olympic swimming pool, give or take. Fuel supplies around 94 per cent of that and urine about 6, or 154 tonnes of ice. At that altitude people drink hard, and the camp produces more than 6,000 litres of urine a day. Solids are collected in barrels and carried down. Most of the liquid goes into the glacier.
Satellites agree that something is happening under the tents. Landsat images from 1991 to 2023 show the surface beneath the camp warming by about 0.28 degrees a year, roughly twice as fast as the glacier beside it. The authors are careful about what that proves. Global warming is the main cause, they say, and their own figures a small share of it; what belongs to the camp is that its heat sits under the busiest patch of the ice. Helicopters, body heat and the yaks were left out, so the real number is larger. And the melt figures are heat converted into an ice equivalent, a first-order estimate rather than a measured loss.
The paper ends with a recommendation: two places to the south-west, on stable ground without ice. Moving would be safer for helicopters, simpler to supply and warmer to sleep on, at the cost of a longer walk to the icefall. Gautam ran the 2019 survey that put the mountain at 8,848.86 metres and has kept an office in the camp since 2022, which is when he first suggested moving it. Nobody has decided. And no tent has yet gone through: this is arithmetic about heat, not a record of accidents.