Ms Schwikowski, the IPICS Conference can finally go ahead after being on ice for two years. Why was Switzerland chosen as the venue, following on from previous conference hosts France and Tasmania?
Margit Schwikowski: Candidates interested in hosting the conference actually have to submit bids beforehand – a bit like the Olympic Games (laughs). So, we are proud to have been given this honour. One of the key strengths of our bid was the fact that we combine both disciplines within ice core research. As PSI representative, my research focuses on high-alpine glaciers. The co-chair of our Organizing Committee, Hubertus Fischer from the University of Bern, represents polar ice core scientists. We have put together an exciting programme for both disciplines and want to promote further exchanges between different specialists.
Can you cite a few highlights?
One important project we will be learning more about is “Beyond EPICA”. EPICA stands for the European Project for Ice Coring in Antarctica. This has already involved drilling more than 3,200 metres into the Antarctic ice cap, providing scientists with the longest continuous time series to date of greenhouse gas concentrations in the atmosphere, stretching back some 800,000 years. The Bern working group led by Hubertus Fischer has been responsible for most of the greenhouse gas measurements. They provide a wealth of information, for example, on shifts between glacial and interglacial periods or rapid climate changes. “Beyond EPICA”, in which our colleagues from Bern are also heavily involved, sets off again to Antarctica this winter, to delve even deeper into the past. The plan is to drill at a location where we expect to find ice that is 1.5 million years old at the bedrock.
What information could this ice provide?
Based on another climate archive – namely marine sediments that extend even further back into the past, but do not offer such precise details about the climate in that particular period – we know that up to roughly a million years ago an ice age cycle lasted around 40,000 years, but then the periodicity changed to some 100,000 years. ‘Beyond EPICA’ could help explain why this happened – potentially due to changes in the CO2 concentration in the atmosphere. Such information improves our understanding of current climate change. That’s why we will also be discussing marine sediments at the conference, as well as new drilling techniques offering better climatic insights extending even further into the past. There will also be a presentation on the comparatively young research field of micro-organisms in deep ice layers. One conclusion taken from this discipline: the ice cores still hold a wealth of information about the Earth’s history and climate in the past – and we are only just starting to explore this scientific treasure.
The Ice Memory project, which you’re involved in, should certainly also be seen against this background. The aim is to collect ice cores from alpine glaciers across the world and store them securely in an ice cave in Antarctica. The cores from the Ice Memory project will then be preserved for younger generations of scientists, who in the future should be able to extract even more information using advanced analytical methods.
Absolutely. Our field of research faces a massive problem: more and more glaciers worldwide are melting and the meltwater percolating into them is destroying all embedded signals locked in there for many thousands of years. It’s a race against time. We’ve seen that not only on the Grand Combin glacier saddle here in Switzerland, where we drilled two years ago and discovered that the ice cores were virtually unusable. Last year we ventured even higher to the Colle Gnifetti on the Italian border – the last alpine glacier where we hoped to find undisturbed ice. But sad to report: the glacier has changed significantly since the last time I visited in 2015. Instead of stamping across the compacted snow (‘firn’) at 4,450 metres, we found ourselves slipping on the icy surface. We even had to use ropes and cut steps into the ice in order to climb up to the Margherita Hut, otherwise it would have been too dangerous.
But isn’t ice important for your research?
Yes, but the glacier should have a looser covering of snow, known as firn. If the surface is ice, it shows us that meltwater has formed in the upper layers and has potentially percolated down into the glacier’s deeper layers as well, thereby disturbing the information held in the ice. On a few days of the year, it’s not so bad if the meltwater just freezes over again under the surface. But this year our colleagues specialising in glaciology found that that the temperature even four metres down in the glacier was around zero degrees. Such high temperatures have never been recorded before at this location. We are glad we still managed to extract good quality ice cores from the site last year, but that could well have been our last chance to do so. Summer temperatures have been so extreme this year, it has been disastrous for glaciers and for our research. This year alone has probably also been very disruptive to the climate archive stored in the Colle Gnifetti.
Will the Ice Memory project also be a discussion topic at the conference?
Climate change obviously casts its shadow over everything. But as far as Ice Memory is concerned: we are holding a workshop after the conference to discuss the way forward. This year we wanted to extract an ice core from the glacier on Kilimanjaro before samples from Africa’s last remaining major glacier perhaps become unusable – in fact it may already be too late. Despite all our efforts, however, we have still not had authorisation from the Tanzanian authorities. That’s frustrating.
Are ice core scientists perhaps becoming disenchanted as they increasingly see their main topic of research gradually melting away under their snowshoes?
That’s true, unfortunately. And it’s particularly the case for researchers working on high-alpine glaciers. Scientists involved with the polar ice cores still have a little more time – although the scale of melting in Greenland, for example, is increasing and making work much more difficult. That means it is even more important for everyone to get together again at the conference and push ahead with our work. Especially since the communal mood, despite everything, is very positive and motivating. Although the ice core community is relatively small – probably no more than about a thousand scientists worldwide – we are a close-knit and happy community. Our work can be tough, occasionally spending weeks at minus 20 degrees on mountain glaciers or ice sheets, and often drilling under harsh weather conditions. But then we celebrate to make up for it. Which is exactly what we do at the conference, once the day’s work is finished.
(Source PSI, Interview: Jan Berndorff)