China-Nepal Team Extracts First Complete Ice Core from Everest Summit

A joint China-Nepal scientific expedition has achieved a historic first: the successful drilling and retrieval of a complete, full-depth ice core from the summit of Mount Everest. The breakthrough, announced on May 23, provides scientists with an unprecedented climate record preserved at the highest point on Earth.

The “Core of the Summit” (巅峰之芯) expedition reached the 8,848.86-meter peak on May 21 via the Nepal-side South Col route and drilled approximately nine meters through the summit ice cap to extract a complete “through-ice” sample, according to Xinhua News. All team members have since descended safely to the South Base Camp.

A Two-Hour Window at the Top of the World

Eight team members departed from Camp 3 at approximately 7,200 meters in the early hours of May 21. After reaching the summit in the early morning hours, the team had roughly two hours to conduct continuous scientific operations in extreme conditions of severe oxygen deprivation and freezing temperatures, as reported by the Global Times.

“This mission’s significance lies not only in reaching the summit, but in completing continuous scientific operations in the extreme environment at 8,848.86 meters,” said Wen Xu, the expedition team leader and a glacier engineering PhD. “The summit ice core samples provide important field samples for subsequent research on climate and environmental changes in the extremely high-altitude regions of Everest.”

Wen Xu, founder of Polar Future (Tianjin Extreme Climate Response Promotion Center), credited the Nepali team members for their critical role. “Their climbing ability is strong, and their experience adapting to and dealing with harsh high-altitude environments is richer. They played a key supporting role in completing this ice core drilling mission,” he told Xinhua.

Filling a Critical Gap in Climate Observation

The summit ice layer on Everest is approximately nine to ten meters thick. While relatively shallow compared to polar ice sheets, it represents the highest-altitude climate record on Earth. Previous attempts had only succeeded in extracting about four meters of ice from the northern (Tibetan) side, leaving the complete climate record at the summit untapped.

Xu Baiqing, chief scientist of the expedition and deputy director of the Institute of Tibetan Plateau Research at the Chinese Academy of Sciences, emphasized the significance of the achievement. “The summit of Everest is the highest geographical point on Earth and remains a major gap in human observation,” he said. “The summit ice core and multi-altitude gradient samples obtained will provide key materials for revealing climate and environmental changes in the world’s highest region and for understanding atmospheric circulation and material transport processes at extreme altitudes.”

Ice cores serve as natural climate archives, with each layer preserving atmospheric gases, dust, pollutants, volcanic ash, and microbial life from the time it was deposited. Scientists can analyze these layers to reconstruct past climate conditions over centuries or millennia.

Scientific Questions the Samples May Answer

The expedition, supported by the UN Decade of Action for Cryospheric Sciences (2025-2034), collected samples across multiple altitude gradients during the descent, creating a vertical climate transect from 6,000 meters to the summit. Researchers hope the samples will help answer several critical questions:

• How is the extremely high-altitude region of the Himalayas changing in response to global warming?
• How high does the Indian monsoon’s influence reach?
• Have South Asian pollutants crossed the Himalayas into the Tibetan Plateau?
• Why do the northern and southern slopes of Everest show different climate responses?

According to Polar Hub, obtaining a full-depth summit ice core marked a major breakthrough, while continued sampling across different altitude gradients will help establish a complete chain of climate and environmental evidence for high-altitude regions.

A Challenging Climbing Season

The achievement came during an unusually difficult spring climbing season on Everest’s south side. Nepal issued a record 492 climbing permits, while the Khumbu Icefall route construction was delayed by approximately two weeks due to unstable ice seracs, compressing the summit window and increasing risks in the “death zone” above 8,000 meters.

What Comes Next

The collected ice core and snow samples will be transported under strict low-temperature preservation conditions to laboratories for detailed analysis, a process expected to take months or even years. The research findings could inform climate models, improve understanding of pollutant transport across the Himalayas, and contribute to the UN Cryosphere Decade’s goals of advancing global cryosphere science.

As Wen Xu noted, the mission represents more than a single achievement: it establishes a complete chain of climate and environmental evidence from the world’s highest peak, offering a window into changes occurring at the roof of the world.