Ice Memory Project: The Race to Preserve Earth’s Past
Glacial ice stores information about our planet’s environmental past, however, climate change is causing it to melt away. UNESCO’s ‘Ice Memory Project’ is racing to extract samples from glaciers around the world and preserve this important data for future scientists.
Illustration by Katie De Lusignan.
Over the last 10,000 years there have been volcanic eruptions, ice ages, and floods. But how do we know this?
Earth’s environmental past has been revealed by studying ice cores extracted from glaciers across the globe. These cylinders of ancient ice contain particles and gases that were present when the ice was formed. Scientists can use these components to determine past global events and the composition of the atmosphere at the time - painting a picture of the last few thousand years of environmental change. They have the potential to reveal information that could guide us as we tackle extreme climate change.
But increasing rates of climate change are causing these glaciers to melt away - more than 9 trillion tonnes of glacial ice was lost between 1961 and 2016. Along with the ice, Earth's valuable past environmental record is also disappearing.
This is where the Ice Memory Project is stepping in.
The Ice Memory Project
Launched in 2015, the Ice Memory Project is an international collaboration with the goal of extracting ice cores from glaciers to create a library of samples for current and future scientists. The team of founding glaciologists were motivated by the increasing numbers of mountain glaciers, and the chemical data they store, that are being endangered by climate change. It is
funded by scientific organisations and private sponsors, as well as being supported by UNESCO (United Nations Educational, Scientific and Cultural Organisation).
The inaugural Ice Memory Conference took place in 2017 and was attended by scientists from 12 countries, during which a roadmap for this ambitious project was determined. Extraction of these ice cores began with initial expeditions to France’s Col Du Dôme glacier in 2016 and Bolivia’s Illimani glacier in 2017.
But how exactly do we get these samples?
Retrieving these ice cores is no mean feat - it involves a team of scientists transporting large loads of equipment while tackling the harsh mountain conditions. The 2017 expedition in Bolivia required scientists to carry over 4 tonnes of essential apparatus, whilst maneuvering three ice cores that represented approximately 18,000 years of Earth's history!
A typical Ice Memory Project mission aims to retrieve 3 ice cores - drilled from the summit of the glaciers where there is minimal mixing of ice and therefore provides an accurate ice record. One of these cores is immediately analysed following the mission. This is to create a detailed public database that will be used by current scientists, but will also be a valuable reference for scientists in the future. The other 2 cores are then transferred to storage - which is it’s own mission!
Following the expedition, the samples are put into short term cold storage but will eventually be transferred to Antarctica for long term storage in snow caves. Chosen for its reliably freezing weather and political neutrality, the French-Italian Concordia research station will house this ice archive by keeping the cores 10m below the surface and at a frosty -54°C. The logistical challenges of relocating the cores to the caves during COVID has caused delays, but they will hopefully start receiving samples in 2023.
Unfortunately, not all of these missions are successful. In October 2020, an expedition led by Dr Margit Schwikowski to the Corbassiére glacier in the Swiss Alps was cut short. While her team was drilling, they repeatedly hit a thick hard layer of ice known as an ice lens. Hitting an ice lens during an extraction is bad news - they form when high temperatures melt glacial surface layers
that then mix with the snow and refreeze as a thick ice sheet. This mixing means the historical record stored in the ice of Corbassiére glacier is now lost. Discovering an ice lens, coupled with dangerous weather conditions, meant this mission had to be abandoned.
How important are these ice cores really?
Glaciers have a relatively young ice record (1000 to 10,000 years) compared to continental ice sheets in Greenland and Antarctica (up to 800,000 years in some locations), therefore extremely long term images of the climate can’t be constructed from them. However, glaciers and their historical record are under more pressure from warming climates, so extraction from these locations have been prioritised by glaciologists.
Ice cores store valuable chemical information that can be analysed to create a timeline of how the planet's climate has changed over the last few thousand years. Within the cores, small bubbles of ancient air are captured - which is a sample of the environment at the time. Analysis of these cores provides a range of useful data, including: past air temperatures, precipitation rates, and pollen levels.
One of the most valuable properties of ice cores is that they are a record of past greenhouse gas levels. From this, we can understand glacial-interglacial cycles (the relationship between the changing climate and atmospheric gas levels) by reconstructing past environments using this data. Understanding these trends may contribute to our understanding of how climate
change will affect our environment.
Along with chemical data, there are new lines of research investigating what we can find out about ancient microorganisms from ice core records. One process involves following how a microorganism and its genes evolved in response to a changing environment. For example, if there are numerous genes related to mercury resistance present in an organisam, this suggests that mercury was present in the environment.
Not only can we reveal important information about Earth's environmental record, we can find evidence of human activity in the past captured within the ice cores. Using carbon-14 dating analysis on samples from the Col du Dôme glacier, evidence of atmospheric pollution from mining activity in Ancient Roman times has been detected. Analysis has also detected a caesium-137 peak, showing that even the 1986 Chernobyl Disaster has left an impact on glacial ice.
Ice cores are not just essential for researching our planet’s past, they can be useful for climate modelling its future. Climate models are a valuable resource, especially during a time of accelerating climate change, which have to be extremely accurate. To calibrate models and test their accuracy, past climates are simulated using data from ice cores.- another reason these samples are vital as we move into a period of increasing climate change.
Extracting these ice cores doesn’t just provide a valuable resource for current scientists, it provides a wealth of data for future generations of researchers. There is hope that future scientists will have access to new techniques and tools that can be used to analyse ice cores even further, potentially unveiling things we can’t today. Due to climate change degrading these glaciers, sadly these glaciers won’t be available for future researchers to study first hand. Therefore, these cores may even be more valuable in the future than they are now.
With current climate forecasts predicting that glaciers will disappear from New Zealand, Europe, and western North America by the end of this century, the Ice Memory Project is more important than ever.
By focusing on our future scientists and the positive discoveries they may make, the ice memory project offers a refreshing perspective during a time of climate-anxiety.
This project will not only make our climate models more robust and our understanding of the environmental past more reliable, it leaves behind a valuable resource for future scientists.
Thank you to Katie De Lusignan for her beautiful illustration. You can find more of her work on her Instagram @myhandsmadethese.
Caitlin Thomas
Caitlin is an aspiring ecologist with a passion for marine ecology and accessibility in science. She is currently interning as an ecological consultant and will graduate in 2022 with an Ecology and Conservation Biology degree from the Uni of Sheffield. After this, she hopes to volunteer with some marine mammal charities. In her free time, she enjoys long hikes, watercolour painting, veggie cooking, and getting involved with science communication charities.
Find her on Instagram @caitlin.ecology or Twitter @CaitlinAThomas2.