China-Nepal team drills first full-depth ice core from Everest summit

Overview

Updated May 25

For nearly three decades, Everest's ice-core record stopped at 6,500 meters on the East Rongbuk Glacier. A joint China-Nepal team has now pulled a full-depth core from the 8,848.86-meter summit.

The samples will be analyzed for the upper boundary of the Indian monsoon and pollutant transport into extreme altitudes. They'll also be analyzed for how Everest's northern and southern slopes respond differently to warming. Summit ice spans a shorter time window than valley cores, but it captures atmospheric chemistry no lower station can see.

Why it matters

Summit ice is the only atmospheric record from Earth's highest point, and once the glacier melts, that data is gone forever.

Questions about this story

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How long is the core that they took? What exactly is "Full Depth" in meters?

The core is approximately 9.5 meters long — that is the full ice thickness at Everest's summit measured by the 2022 radar survey that planned this drill.

Why it matters: Nine-and-a-half meters sounds modest, but it is the entire ice column: drilling 'full depth' means reaching bedrock, not a partial sample, which is what makes this archive complete.

A May 2022 ground-penetrating radar survey by Xu Baiqing's team found mean ice/snow depth at the Everest summit to be 9.5 ± 1.2 meters — far deeper than the 0.9–3.5 m estimates from the previous five decades.
That 2022 radar work was explicitly designed to set drilling targets for this expedition, so the 2026 core should match that ~9.5 m full-thickness figure.
'Full depth' means the drill went from the surface all the way to bedrock, capturing the entire summit ice column rather than stopping at a set length — a distinction that matters for completeness of the climate record.
For comparison, the previous Everest-region record cores from the East Rongbuk Glacier (6,518 m) reached up to 108 meters — longer because valley glaciers are far thicker than summit ice caps.

Sources

Room for disagreement

The 9.5 m figure is the radar-measured ice thickness, not a confirmed published length for the 2026 core itself — Chinese state media and wire reports describe it as 'full depth' without stating a meter figure, so the exact core length awaits the scientific paper.

AI-generated with web search — may be wrong. Check the linked sources.

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WHat does "full-depth" mean?

"Full-depth" means the drill went all the way through the ice to the bedrock underneath — capturing the entire climate record preserved in that location, not just the upper portion.

Why it matters: Stopping short of bedrock means missing the oldest ice; hitting bedrock guarantees researchers got everything the site has to offer.

In 1998 and 2002, teams drilled Everest's East Rongbuk Glacier at ~6,500 m and eventually reached bedrock there, pulling cores up to 108 meters long.
For the summit, the 2022 radar survey first mapped exactly how thick the ice is at 8,848 m — that data told the 2026 team how far to drill to call it 'full-depth'.
The summit core is much shorter than valley cores (summit ice is thinner), so it covers a shorter time window — but it's still the complete record that location holds.

AI-generated with web search — may be wrong.

Key Indicators

8,849 m

Summit drilling altitude

The team drilled at the summit itself, 8,848.86 meters above sea level.

First

Full-depth summit ice core

No prior expedition has extracted a core from the Everest summit itself.

2,349 m

Elevation gain on prior Everest cores

Earlier Everest ice cores came from East Rongbuk Glacier at 6,500 meters.

Glaciers around Everest thinned 100+ m

Sixty-year measurements show widespread thinning, with the rate roughly doubling since 2009.

Voices

Curated perspectives — historical figures and your fellow readers.

Ever wondered what historical figures would say about today's headlines?

People Involved

Xu Baiqing

Chief scientist, Core of the Summit mission

Leading analysis at the Institute of Tibetan Plateau Research

Wen Xu

Expedition leader, Core of the Summit mission

Returned from summit; transporting samples to laboratories

Yao Tandong

Director, Institute of Tibetan Plateau Research

Coordinates the Second Tibetan Plateau Scientific Expedition program

Organizations Involved

Institute of Tibetan Plateau Research

Research institute

Leading the 2026 expedition; will house and analyze the ice cores

The Chinese Academy of Sciences institute that runs long-term glacier and climate research on the Tibetan Plateau.

Timeline

September 1998 May 2026

6 events Latest: May 25th, 2026 · 4 months ago

Tap a bar to jump to that date

May 2026
Expedition announces successful summit ice-core extraction
Latest Announcement

Chinese and Nepali agencies confirm the cores are in low-temperature transport to laboratories for analysis of monsoon, pollutants, and slope-by-slope warming.
May 25th, 2026
China-Nepal team reaches summit and drills full-depth core
Expedition

The Core of the Summit team reaches 8,848.86 meters and completes the first full-depth ice-core extraction from the Everest summit in about two hours.
May 21st, 2026 • 7:30 AM
May 2022
Earth Summit Mission reaches Everest summit
Expedition

Thirteen Chinese researchers run the first radar mapping of summit ice thickness and install the world's highest weather station at 8,830 meters.
May 4th, 2022
January 2017
Second Tibetan Plateau Scientific Expedition launches
Program

China launches a multi-decade research program covering glaciers, water, and ecology across the Tibetan Plateau.
January 1st, 2017
October 2002
Bedrock cores recovered from East Rongbuk Glacier
Research

Researchers drilled to bedrock at 6,518 meters, producing cores up to 108 meters long for monsoon and pollutant studies.
October 1st, 2002
September 1998
First Everest ice cores drilled at East Rongbuk
Research

An early Chinese-American team recovered ice cores at 6,500 meters on the East Rongbuk Glacier, far below the summit.
September 15th, 1998

Scenarios

First peer-reviewed paper on summit cores published by mid-2028

Likely Resolves by May 25, 2028

Discussed by: Implied by Chinese Academy of Sciences and Institute of Tibetan Plateau Research statements describing planned laboratory analysis

The cores travel under cold-chain preservation to ITP laboratories in Beijing. Prior ITP Everest cores have produced first English-language papers within 18 to 30 months. Analysis of the upper layers, chemistry, and dust deposition usually publishes before deeper paleoclimate work.

IPCC AR7 cites Everest summit ice-core findings

Possible Resolves by Q2 2030

Discussed by: IPCC working group timelines; cryosphere chapter authors

The next IPCC Assessment Report cycle is scheduled to complete its main working group reports between 2028 and 2029. If summit-core chemistry yields new constraints on Asian monsoon variability or pollutant transport, those results could enter the AR7 reference list.

A second full-depth Everest summit core is extracted within three years

Uncertain Resolves by May 25, 2029

Discussed by: Coverage in Global Times and Chinese Academy of Sciences releases framing the 2026 trip as part of an ongoing program

Glaciologists often re-drill to verify dating and capture additional layers. The 2022 weather station and 2026 drilling protocols make a repeat extraction much cheaper than the first one. A second drilling would also let teams compare cores from the northern and southern routes.

Historical Context

3 moments from history that rhyme with this story — and how they unfolded.

1998–2002

East Rongbuk ice cores (1998–2002)

Joint Chinese-American teams drilled ice cores on the col of the East Rongbuk Glacier at 6,500 meters on Everest's north side. The 2001 and 2002 drilling reached bedrock, yielding cores of 117, 108, and 95 meters. Analyses produced the first long records of Asian monsoon variability and pollutant deposition from the Everest region.

Then

Papers in the mid-2000s mapped seasonal dust, trace metals, and snow chemistry on the north slope.

Now

The East Rongbuk dataset became the benchmark Everest ice-core record for two decades and the comparison point for every later high-altitude drilling project.

Why this matters now

Every prior Everest ice-core study came from this lower-elevation glacier. The 2026 summit cores test whether the chemistry seen at 6,500 meters holds at the actual peak.

September 1997

Dasuopu ice cores, Shishapangma (1997)

Lonnie Thompson's team from Ohio State drilled three ice cores at 7,200 meters on the Dasuopu Glacier of Mount Shishapangma, then the highest ice-core record in the world. One core reached bedrock at 168 meters and captured more than a thousand years of climate history.

Then

The cores documented a sharp rise in dust and lead beginning in the Industrial Revolution.

Now

Dasuopu held the record for highest ice core extraction for 29 years until the 2026 Everest summit drilling.

Why this matters now

Dasuopu showed that high-altitude Himalayan cores can hold readable records over centuries. The Everest summit core surpasses it by 1,649 meters, but wind scour at the summit means the new record will likely cover a shorter span.

April–May 2022

Earth Summit Mission (2022)

Yao Tandong led roughly 200 scientists across multiple Everest research teams. On May 4, 2022, thirteen researchers reached the summit and ran the first radar map of summit ice thickness. The team installed the world's highest automatic weather station at 8,830 meters and flew an observation balloon above 9,000 meters.

Then

The weather station began returning continuous temperature, wind, and humidity data from the upper Everest atmosphere.

Now

The 2022 radar survey identified where the summit ice was thick enough to drill a full-depth core, and the weather station gave teams real-time conditions for summit work.

Why this matters now

The 2026 expedition is the operational follow-up to 2022. Without the radar map and the on-summit weather station, the full-depth drilling would have been far harder to plan and execute.