Melting glaciers are destroying a valuable record of Earth's climate

The relentless acceleration of global warming has now claimed an unexpected victim: our understanding of Earth’s past climate. 

A recent study led by the Ice Memory initiative has revealed a sobering reality. The rapid melting of the Corbassière glacier, located in the Grand Combin massif, has destroyed what was once a valuable record of climate data.

The Ice Memory initiative

The Ice Memory initiative is a collaboration involving researchers from the Paul Scherrer Institute (PSI), the University of Fribourg, Ca’ Foscari University of Venice, and the Institute of Polar Sciences of the Italian National Research Council.

The team analyzed ice cores drilled in 2018 and 2020 from the Corbassière glacier. Their goal was to preserve the precious climate records held within these glaciers.

Loss of climate data

The researchers discovered significant differences between the two sets of ice cores. The 2018 core, extending up to 14 meters and containing records back through 2011, displayed the expected seasonal fluctuations in trace substances like ammonium, nitrate, and sulfate. These substances, usually deposited through snowfall, provide a seasonal account of air pollution and climate conditions.

By contrast, the 2020 core, drilled up to 18 meters under the guidance of PSI researcher Theo Jenk, revealed a disturbing trend. Only the uppermost layers showed the expected seasonal fluctuations. 

Deeper layers, representing older records, showed a flattening of these fluctuations and a reduced total amount of trace substances. This anomaly points to a significant loss of climate data, comparable to a library losing its books and the remaining ones being scrambled beyond recognition.

Accelerated glacier melting

The researchers attributed this loss to enhanced melting between 2018 and 2020, causing surface water to penetrate deeper into the glacier, washing away the trace substances. 

This process not only diluted the records but also permanently removed them, effectively erasing parts of the glacier’s historical climate record.

A threshold has been crossed 

The researchers examined the meteorological data from 2018 through 2020 and found that it was warm on the glacier in line with the general climate trend, but these years were not extreme outliers. 

“From this we conclude that there was no singular trigger for this strong melting, but that it resulted from many warm years in the recent past,” said Margit Schwikowski, head of the Laboratory for Environmental Chemistry at PSI. “It seems a threshold has been crossed, which now has led to a comparatively strong effect.”

Broader implications 

The implications of this discovery extend far beyond the Corbassière glacier. It signals a more dynamic and rapid progression of glacier melting than previously anticipated, affecting even the highest parts of alpine glaciers where ice replenishment occurs. 

The research suggests that many other glaciers worldwide might be losing their ability to serve as climate archives.

Collecting ice from endangered glaciers 

The Ice Memory Foundation aims to collect ice cores from 20 endangered glaciers over 20 years. These cores are intended to be stored in an ice cave at the Concordia research station in Antarctica. This initiative is crucial as it provides a potential safeguard against the complete loss of glacial climate records. 

However, the experience at Grand Combin, where the team faced insurmountable difficulties in drilling and preserving the ice core, highlights the urgency and challenges of this mission.

The Ice Memory project is a race against time, with setbacks like those experienced at Grand Combin becoming increasingly common. While successful cores have been obtained from other locations like the Col du Dôme glacier and Colle Gnifetti, the failure at Grand Combin serves as a stark reminder of what is at stake.

The study is published in the journal Nature Geoscience.

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates.

—–

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.