Glaciers contain valuable information about past environments on Earth within the layers of ice that accumulate over hundreds or thousands of years. However, alpine glaciers have lost 50 percent of their mass since 1850, and projections suggest that glaciers below 3500m will not exist by 2100. Concerns about the loss of this valuable resource motivated Jérôme Chappellaz, a senior scientist at France’s National Center for Scientific Research (CNRS), and an international team of glaciologists, to create the world’s first archive of ice cores from different parts of the world.
Ice cores are cylindrical sections of ice sheets or glaciers collected by vertical drilling. Chemical components within different layers of ice in glaciers, such as gases, heavy metals, chemical isotopes (forms of the same element with different numbers of neutrons in their nuclei) and acids, allow scientists to study past atmospheric composition and to draw inferences on environmental variables such as temperature changes and sea levels. Cores will be extracted between now and 2020, after which they will be transported for storage to Concordia Station in Antarctica, a joint French-Italian base located on the Antarctic Plateau. Antarctica serves as a natural freezer, allowing the cores to be stored 10 meters below the surface at temperatures of -54°C. International management of the archive, which will be large enough to contain cores from up to 20 glaciers, will be facilitated by the lack of territorial disputes in Antarctica.
The first cores that will go into the archive were collected in summer 2016 between August 16th and 27th. Over this time period, two teams of French, Italian and Russian researchers successfully collected three ice cores, each 130 meters long and 92 millimeters in diameter, from France’s Col du Dôme glacier (4300m above sea level) on Mont Blanc, the highest mountain in the Alps. Drilling was carried out within drilling tents at nighttime because daytime temperatures were too high. The cores were then cut into one meter sections for storage and transportation purposes.
“The cores are currently stored in our commercial freezers at Grenoble, France, waiting for the long term storage cave at Concordia Station in Antarctica to be built,” Chappellaz told GlacierHub. “One of the three cores will be used during the coming two years to produce reference records of all tracers (chemical components of ice that reveal information about the natural environment) that can be measured with today’s technologies.”
The next drilling for the archive will take place in May 2017 at Illimani glacier in the Bolivian Andes (6300m above sea level). As with the drilling at Col du Dôme glacier, the project will be overseen by Patrick Ginot, a research engineer at the Laboratory of Glaciology and Environmental Geophysics (LGGE) in Grenoble. The collection of ice cores has relied on intense international collaboration, and Ginot will be working with glaciologists from Bolivia to extract the cores.
Illimani is one of the few Latin American glaciers that contains information stretching back to the last glacial maximum around 20,000 years ago. Although ice cores collected from the Arctic and Antarctica, such as those from Dome C, provide information stretching back to that period, the value of the cores lies in the information they are able to provide about specific regions. For example, ice cores from France’s Col du Dôme glacier can provide information about European industrial emissions, while ice cores from Bolivia’s Illimani glacier could offer insight into the history of biomass burning in the Amazon basin.
Glaciers will be selected based on a number of criteria, with priority given to glaciers that contain large amounts of information about the regions from which they are collected, that are in significant danger of melting, and for which relevant expertise is available. Col du Dôme glacier was chosen by Chappellaz and his team as the first site because it met this criteria, while the proximity of the site to the CNRS laboratory allowed the starting budget to cover the logistics of the project.
Gaining funding has been one of the main obstacles to the creation of the archive, according to Chappellaz. “As we are not the scientists who are going to perform new science on the heritage ice cores, the usual funding agencies for science are not really interested by the project. Therefore, we had to build it entirely around donations,” he explained. Nevertheless, the project is gaining ground, with future plans to extract ice cores from Colle Gnifetti glacier at the Italian-Swiss border, Mera glacier in Nepal, the Huascaran glacier in Peru, and Mount Elbrus in the Caucasus Mountains in Russia. More information about current and future plans can be found here.
Scientists participating in these plans to extract cores from these regions hope to be able to preserve a valuable resource that will be the property of the international community. They are in discussions with UNESCO and the United Nations Environment Programme to coordinate the creation of a political and scientific governing body to manage the ice core archive.
Further uses for these ice cores will depend on the development of scientific ideas and technology, which may allow new aspects of data within the ice to be analyzed. However, as Chappellaz suggested, “What we can already indicate is that studies of the biological content in the ice, such as bacteria and viruses, will probably become an important area for ice core science in the future, with possible applications in medical research.” As such, efforts to preserve rapidly disappearing resources not only enhance our understanding of Earth, but could also allow for new uses yet to be discovered.