‘Extremely Exciting’: The Ice Cores That Could Help Save Glaciers

AFP/APP

Sapporo: Dressed in an orange puffer jacket, Japanese scientist Yoshinori Iizuka stepped into a storage freezer to retrieve an ice core he hopes will help experts protect the world’s disappearing glaciers.

The fist-sized sample drilled from a mountaintop is part of an ambitious international effort to understand why glaciers in Tajikistan have resisted the rapid melting seen almost everywhere else.

“If we could learn the mechanism behind the increased volume of ice there, then we may be able to apply that to all the other glaciers around the world,” potentially even helping revive them, said Iizuka, a professor at Hokkaido University.

“That may be too ambitious a statement. But I hope our study will ultimately help people,” he said.

Thousands of glaciers will vanish each year in the coming decades, leaving only a fraction standing by the end of the century unless global warming is curbed, according to a study published Monday in the journal Nature Climate Change.

Earlier this year, AFP exclusively accompanied Iizuka and other scientists through harsh conditions to a site at an altitude of 5,810 metres (about 19,000 feet) on the Kon-Chukurbashi ice cap in the Pamir Mountains.

The area is the only mountainous region on the planet where glaciers have not only resisted melting but have even slightly grown — a phenomenon known as the “Pamir-Karakoram anomaly”.

The team drilled two ice columns approximately 105 metres (345 feet) long from the glacier.

One core will be stored in an underground sanctuary in Antarctica belonging to the Ice Memory Foundation, which supported the Tajikistan expedition along with the Swiss Polar Institute.

The other was shipped to Iizuka’s facility at the Institute of Low Temperature Science, Hokkaido University in Sapporo, where the team is searching for clues about why precipitation in the region increased over the last century and how the glacier has resisted melting.

Some researchers link the anomaly to the region’s cold climate or even increased agricultural water use in Pakistan that creates more vapour. However, the ice cores offer the first opportunity to examine the phenomenon scientifically.

‘Ancient Ice’

“Information from the past is crucial,” said Iizuka.

“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.”

Since the samples arrived in November, his team has worked in freezing storage facilities to log the density, alignment of snow grains and the structure of ice layers.

In December, when AFP visited, scientists were dressed like polar explorers to cut and shave ice samples in the comparatively mild minus 20 degrees Celsius of their laboratory.

The samples can reveal weather conditions going back decades or even centuries

A layer of clear ice indicates a warm period when the glacier melted and refroze, while a low-density layer suggests packed snow rather than ice, helping scientists estimate precipitation.

Brittle samples with cracks indicate snowfall on half-melted layers that later refroze.

Other clues also emerge. Volcanic materials such as sulfate ions can serve as time markers, while water isotopes reveal temperature changes.

Scientists hope the samples contain material dating back 10,000 years or more, although much of the glacier melted during a warm spell around 6,000 years ago.

Ancient ice could help answer questions such as what kind of snow fell in the region 10,000 years ago and what particles it contained, Iizuka said.

“We can study how many and what kinds of fine particles were suspended in the atmosphere during that ice age,” he added.

“I really hope there is ancient ice.”

Secrets in the Ice

For now, the work proceeds slowly and carefully, with team members such as graduate student Sora Yaginuma meticulously slicing samples apart.

“An ice core is an extremely valuable and unique sample,” said Yaginuma. “From that single ice core, we perform a variety of analyses, both chemical and physical.”

The team hopes to publish its first findings next year and expects to conduct extensive trial-and-error work to reconstruct past climate conditions, Iizuka said.

Analysis at Hokkaido will uncover only part of the ice’s story. With additional samples preserved in Antarctica, future research opportunities will remain open.

Scientists may, for instance, search for clues about how historical mining activities affected air quality, temperature and precipitation in the region.

“We can learn how the Earth’s environment has changed in response to human activities,” Iizuka said.

With so many secrets still locked in the ice, the work is “extremely exciting,” he added.