Preserve the ice memory for future generations

Objectives and key results

Number of ice cores drilled: 2 deep ice cores
Drilling depth: 104.7 m and 105 m
Climate record retrieved: Approximately 700 years

• 1 core dedicated to contemporary laboratory analysis
• 1 core dedicated to long-term preservation in Antarctica

In October 2025, the international PAMIR Project team — flagship initiative of the Swiss Polar Institute — successfully drilled two deep ice cores to bedrock on the endangered Kon Chukurbashi Glacier in eastern Tajikistan.

Why this site?

The Kon Chukurbashi Glacier (5,814 m) is located in the Eastern Pamirs, within the high-altitude region known as the Third Pole — the largest ice reservoir outside the Arctic and Antarctica.
This glacier was selected because of:

• Its climatic and scientific relevance
• Its geostrategic importance in a region facing increasing water stress
• Its high vulnerability to accelerating warming
• Its connection to the Pamir–Karakoram anomaly, a phenomenon that has led to temporary glacier mass stability or growth despite global warming

However, recent observations suggest that this anomaly may be coming to an end — increasing the urgency of preserving its climate archive.

The expedition

Period: October 2025
Altitude: 5,814 m
Conditions: High altitude, low oxygen, unpredictable weather, remote access

Despite extreme logistical challenges — including altitude constraints, limited oxygen, and difficult transport conditions — the team successfully drilled two complete cores to bedrock.
The expedition was conducted under the PAMIR Project, led by Evan Miles (Universities of Fribourg and Zurich) in close partnership with the National Academy of Sciences of Tajikistan.
Local logistics experts and Tajik porters played a crucial role in ensuring operational succes.

The team

The international scientific team included:

• Tomas Saks, University of Fribourg
• Stanislav Kutuzov, Ohio State University
• Yoshinori Iizuka, Hokkaido University
• Jahongir Abdullov, Tajik Academy of Sciences
• Zebokhonym Khushnazarova, Tajik Agency of Hydrometeorology
• Jovidon Ochildievich, Academy of Sciences of Tajikistan
• Koji Fujita, Nagoya University
• Sumito Matoba, Hokkaido University
• Ivan Lavrentiev, Russian Academy of Sciences
• Ken Kondo, Nagoya University
• Enrico Mattea, University of Fribourg
• Andreas Henz, University of Zurich
• Hikaru Kondo, Hokkaido University
• Sora Yaginuma, Hokkaido University

Scientific analysis

The first ice core is currently being analyzed at the Ice Core Laboratory of the Institute for Low Temperature Science, Hokkaido University (Japan).
Initial analyses include:

• Bulk density
• Stable water isotopes
• Tritium
• X-ray transmission imaging
• Near-infrared reflectance
• Grain size and stratigraphy
• Impurity, dust and debris content

Future analyses will include ion concentration measurements and radiocarbon (C14) dating of deeper layers.
The first 40 meters are expected to be fully analyzed within one year, including basal dating.

A historic donation

On October 13, 2025, during an official ceremony in Dushanbe, the Government of Tajikistan formally donated the two ice cores:

• One core to the PAMIR Consortium for collaborative scientific analysis
• One core to the Ice Memory Foundation for long-term preservation in Antarctica

This marks the first official donation to the international scientific community within the framework of the UN Decade of Action for Cryospheric Sciences (2025–2034).

Expedition partners and support

This drilling operation was funded by the Swiss Polar Institute (SPI), with the support of the Ice Memory Foundation.

Scientific partners included the Universities of Fribourg and Zurich, the National Academy of Sciences of Tajikistan, Hokkaido University, Nagoya University, Ohio State University, and the Russian Academy of Sciences.