| ||N° 40 - February 2004|
| PORTRAIT - Ice seasons
A number of multidisciplinary teams are currently engaged in the study of polar regions, a knowledge of which is vital to understanding climate change. One of these explorers of this icy world is the German oceanographer Ursula Schauer. A slightly built woman with unquestionable scientific and moral authority, she confronts the unknown with remarkable calmness. Whether as mission leader or researcher on a specific project, she spends months at a time on board her old friend, the Polarsternicebreaker.
After studying the Baltic Sea bight off Kiel, Ursula Schauer became one of Germany’s first women physical oceanographers. She remembers raising a few eyebrows during the first 10 years of her career, but never had the feeling her gender worked against her. ‘Provided there is an understanding environment, the researcher's life can become a collective adventure. My family follows all my trips, checking where I am every day. When she was small, my daughter thought the Polarstern was my boat,' she confesses.
In fact the Polarstern belongs to the Alfred Wegener Institute for Marine and Polar Research located in Bremerhaven, northern Germany. Rarely at the quayside, this icebreaker spends most of the year sailing the polar seas, usually the Arctic waters in summer and the Antarctic waters in northern winter. Ursula Schauer, a researcher with 13 years' polar experience, generally leaves with the ship every other year, on missions lasting from several weeks to several months.
Attraction of the poles
Her attraction to the poles was not immediate. As a student at Kiel, Ursula was content with day trips on the Baltic Sea and the chance to observe the exchanges between the Baltic and North Sea waters. Later, during her first contract with the German Hydrographic Institute in Hamburg, she analysed the conditions for conserving radioactive waste dumped at sea. This is when she learned how to measure deep-sea micro-currents – as well as the importance of international contacts. 'I remember a violent storm that forced us to seek shelter in the Faeroe Isles. A number of other vessels had done the same thing. It was a very special opportunity to meet researchers from all over the world,' she recalls.
After this applied science phase she signed a contract with the Institute for Marine Research at Hamburg University. It is there that she was to discover the Far North, while studying convection currents in the Greenland Sea. It proved a revelation. What is more, her boss appointed her as mission leader. 'I was astounded. I did not know the boat, the people or the problem. But I told myself that if he thinks I can do it, it means I must be capable. I started to read all the literature on polar seas while I was on board. I wanted to make it a success.' Mission accomplished! At the end of 1989 she was offered a permanent post at Bremerhaven. Since then the poles have determined the rhythm of her life.
Ursula Schauer knows the Polarstern as if she had built it herself. She can explain the reason for every cable, every nut and bolt, every measuring instrument. Everything in fact that goes to make up a unique vessel, from its technical characteristics as a particularly powerful and manoeuvrable icebreaker to its nine scientific laboratories equipped with many devices, some of them submersible. 'Each immersed instrument has an electrical connection six thousand metres long. You can imagine the mechanical stress on the cables, the importance of the rolling out and rolling in operations. Of course, each system also has a back-up to avoid breakdown. The boat also has its own workshop on the lower deck able to make just about anything that may be needed,' Ursula explains. There are no fewer than seven decks on this icebreaker able to carry, with complete autonomy, up to 50 scientists and 40 crew on missions lasting several months – plus the two helicopters!
This floating village is also a science village. Each expedition is multidisciplinary and multilingual. 'Polar research is essentially international. We need the best experts from many disciplines – biology, geology, geophysics, glaciology, chemistry, oceanography, meteorology, etc. It is often the nature of the overall programme that indicates who should be appointed as scientific manager.' Of her seven scientific missions on the Polarstern, Ursula Schauer has headed three. On these trips, she cannot be involved in a specific research project. 'Leading a mission requires constant attention. You have to reconcile the objectives of all the teams, plan the stations so that everyone can gather data, keep in mind the technical constraints and also deal with the most commonplace practical problems,’ she says. ‘I will never forget my surprise, during my first trip as mission leader, when I realised that everyone was counting on me to decide who would be sharing a cabin with who. I didn't know most of them, but it was up to me to decide.'
Depending on whether she sets sail as a researcher or chief scientist, the trip is very different. Ursula Schauer likes them both. While often working on very advanced research projects, she also has the global vision enabling her to include different approaches within a common perspective.
Water, ice and climate
'For a long time oceanography, as well as the study of polar regions, were quite static branches. By that, I mean that the temperature and salinity of deep waters were believed to be constant, to the point where they were used as references for calibrating instruments. Today, we know that these are changing parameters, as are ocean currents and ice thickness. They are a part of the varying climate,' she notes. Conditions in the polar oceans are closely linked to the atmosphere. The key question is to determine to what extent changes are natural and to what extent they could be the result of increased greenhouse gases. For this, we must compile and test models, Ursula explains. 'The reality is complex and we can only grasp parts of it. In meteorology – the very short-term study of climate – we have quite good models based on the initial state of the atmosphere that provide forecasts on how it will develop. If we want to progress to climatic modelling, we must also include the state of polar ice and of the oceans because these interact with the atmosphere. But our knowledge of these is still poor.'
The first task of research is therefore to gather data on the state and flows in the vast reservoirs made up of water and ice. Observation is the starting point for modelling. Science is now beginning to realise how surface phenomena, such as wind and temperature, interact with the ocean depths to a much greater degree than previously thought.
Cruise in the dark
Ursula Schauer's last mission was in the winter of 2003, not in the waters of the Antarctic, as would be expected for the season, but in the Arctic. 'I was appointed scientific director of this mission because I initiated it. At first, it was not easy convincing the scientific committee that selects the projects, but other teams backed us and we finally won approval. We knew the trip would take place under relatively difficult conditions because the ice would be thicker and therefore progress slower at that time of year. In fact this caused us to cancel part of the programme. The data collected are nevertheless exciting and many researchers would like to go for further winter expeditions.'
Important processes of water-air-ice exchange, such as the formation of the Arctic ice pack, take place in winter rather than in summer and we have nearly no observations of them. The formation of ice also affects water salinity. Salt increases significantly the density of the surface water that descends to the ocean depths, thereby giving rise to major convective currents which do not exist in summer. It is therefore essential to also record observations of polar regions in this season too, Ursula stresses. One thing is certain, the Polarstern was not designed for a quiet life.