In an effort to better understand this transformation, a research team led by BC3 researcher Nicolás González-Santacruz performed an in-depth microstructural analysis of a 2017 ice core from Monte Perdido Glacier. This analysis was conducted in BC3’s specialized low-temperature lab, Izotzalab, and specifically focused on a 20 cm section of the core that was marked by a noticeable layer of reddish-brown impurities.

The study revealed that these impurities significantly modify the internal ice structure. González-Santacruz elaborates, “We found a direct link between increased particle presence and the occurrence of smaller and more irregular—less rounded—ice grains, which, according to many previous studies conducted on polar ice, are likely to facilitate the glacier’s internal movement.” This discovery raises critical concerns about the future of the Monte Perdido Glacier. It is assumed by the researchers that the observed microstructural changes could accelerate the glacier’s flow towards warmer, lower areas, resulting in faster melting. These results can provide us clues about what is happening in glaciers with similar characteristics around the world; that is, small glaciers close to large population centers.

The question remains: where do these particles originate, and how do they become embedded in the glacier’s structure? The team’s investigation suggests that the particles in the Monte Perdido Glacier ice core likely originated from past Sahara desert dust deposition events, which will be more frequent in the near future in the Pyrenees due to climate change. Nevertheless, the sources of such impurities can be diverse. They may include volcanic ash or emissions from human activities, with the latter being particularly significant for mountain glaciers located near human settlements. Over time, the particles are gradually covered and buried by successive snowfalls. As the snow transforms into ice, it entraps some of these particles, integrating them permanently into the ice’s structure.

Given the exploratory nature of this study, there is an urgent need for additional research. González-Santacruz emphasizes, “It’s crucial to build upon our findings and validate them through further investigations. While mountain glaciers haven’t been the central focus of microstructural analyses in the past, they are integral to our understanding of regional environmental impacts. Therefore, prioritizing them and allocating more resources for their research is essential”. He alludes to the historical focus of ice flow research on the expansive ice sheets of Greenland and Antarctica, valued especially for their thick layers of ice that preserve long, continuous records of Earth’s climate history. However, while the temporal record in mountain glaciers is shorter and more complex than that in polar regions, their study is equally important. Their closeness to densely populated regions makes them invaluable for providing a detailed record of human activities, heightening their significance in the context of climate change and associated processes like global warming.

An accelerated decline in mountain glaciers would not only represent a substantial loss for research. Even more alarmingly, it would have far-reaching environmental and economic implications: while both polar and mountain glacier melting contribute to sea level rise, the melting of mountain glaciers also affects freshwater availability. As essential sources of fresh water, the decline of these glaciers can lead to water scarcity, significantly affecting agriculture, wildlife, and human communities, particularly in regions dependent on glacial meltwater.

This study holds promise for significantly contributing to the preservation of this unique ecosystem in the long term and advancing our comprehension of the effects of climate change in high mountain regions. The analysis of Monte Perdido’s ice core represents an important step forward in glaciological research, providing valuable insights into glacier dynamics and enhancing our capacity to predict glacier behavior in response to changing climate patterns.

Access the full study here.