Japanese glaciologist Yoshinori Iizuka and an international team drilled two ~105-metre ice cores from the Kon-Chukurbashi ice cap in the Pamir Mountains to investigate the Pamir-Karakoram anomaly, where glaciers have resisted melting. One core is archived in Antarctica and the other is being analyzed at Hokkaido University to study layer structure, density, isotopes and volcanic tracers. The cores may preserve records stretching back up to 10,000 years, offering insight into past precipitation and climate; initial results are expected next year.
How Ice Cores From the Pamirs Could Help Save the World’s Glaciers
A researcher at Japan's Hokkaido University Institute of Low Temperature Science cuts a slice from an ice core sample taken from a glacier in the Pamir mountain range in Tajikistan (GREG BAKER)(GREG BAKER/AFP/AFP)
Dressed in an orange puffer jacket, Japanese glaciologist Yoshinori Iizuka opened a storage freezer to withdraw a fist-sized ice core he hopes will yield clues to protect the world's vanishing glaciers.
The small sample was taken from a much larger effort: an international team drilled two roughly 105-metre (328-foot) ice columns from the Kon-Chukurbashi ice cap in Tajikistan’s Pamir Mountains to study the puzzling Pamir-Karakoram anomaly — one of the few high-mountain regions where many glaciers have resisted shrinking and in some cases grown slightly.
A Split Archive: Antarctica and Sapporo
One of the extracted cores is stored in an underground cold repository in Antarctica managed by the Ice Memory Foundation, while the other was shipped to the Institute of Low Temperature Science at Hokkaido University in Sapporo. The expedition was supported by the Ice Memory Foundation and the Swiss Polar Institute.
Why These Ice Cores Matter
Scientists hope the cores will reveal why precipitation increased in the region over the last century and how the glacier has resisted melting. Iizuka says that understanding the mechanisms behind local ice growth could eventually inform broader glacier conservation efforts — though any application to other regions would be complex and is not guaranteed.
"Information from the past is crucial. By understanding the causes behind the continuous build-up of snow from the past to the present, we can clarify what will happen going forward and why the ice has grown," said Iizuka.
Methods and Clues Encoded in Ice
The team is carrying out careful physical and chemical analyses in controlled cold rooms. Methods include logging layer structure, density and grain alignment; measuring water isotope ratios to reconstruct past temperatures; and identifying volcanic markers such as sulfate peaks to provide chronological anchors. Clear ice layers typically indicate past melt-refreeze events, low-density layers point to packed snow and higher precipitation, and brittle or cracked samples can signal snowfall on partially melted surfaces.
Researchers hope portions of the cores preserve ice up to 10,000 years old, although a warm interval around 6,000 years ago caused partial melting of the glacier. If ancient ice survives, scientists can analyze trapped particles and aerosols to learn about past atmospheric composition and regional climate conditions.
Careful Work, Big Potential
Graduate student Sora Yaginuma and colleagues proceed deliberately: slicing samples, running multiple chemical and physical tests, and cross-referencing results with the Antarctic-held core. The team expects to publish initial findings next year, while more detailed studies — including investigations of historical mining impacts on air quality and regional climate — could follow using the preserved Antarctic samples.
"An ice core is an extremely valuable and unique sample," Yaginuma said. "From that single ice core, we perform a variety of analyses, both chemical and physical."
With many questions still locked in the ice, the researchers describe the work as "extremely exciting" — and potentially illuminating for efforts to understand and conserve glaciers worldwide.
