November 2020 − Bright Minds
With the help of satellite images, Angelika Humbert studies the ice sheets of the Arctic and Antarctica. Her findings contribute to a better understanding of climate change and rising sea levels – and to finding possible solutions.
Explaining her work as a glaciologist, Professor Dr. Angelika Humbert likes to compare the movement of the polar ice sheets to honey. If she were instead to speak of topographical factors and conditions, flow rate and supraglacial lakes, she would leave most conversation partners completely in the dark. “Similar to honey on bread”, Humbert begins to explain, “- this is how glaciers flow once their mass has become large enough from plenty of snowfall. Glaciers flow to the edge of the ice shields of the Arctic and Antarctica, where they will then break off.”
These broken-off icebergs have long since become a symbol of climate change. Global temperatures rise, ice sheets melt, sea levels rise. “The breaking off of ice is a completely natural phenomenon”, says Humbert. “What we are worried about, though, is the speed at which this occurs.”
Humbert has been studying the movement of ice for 20 years; for the past eight years she has been based at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI). Her area of expertise: glacial modelling and remote sensing of ice. For the ice scientist, too, climate change presents the most pressing question of our time. With her work, she can further the understanding of the mechanisms by which glaciers change, and her model calculations can contribute to finding solutions to the problems presented by rising sea levels. “It is likely too late to stop this process entirely, but if we are successful in reducing the temperatures, there is a chance that glacial melting could at least be stabilized.”
Science of societal relevance
According to the Intergovernmental Panel on Climate Change, 680 million people who live in the low-lying coastal regions around globe, 65 million inhabitants of island nations and 670 million people who live in alpine regions are threatened by rising sea levels and melting ice, with a simultaneous increase in extreme weather phenomena. “We are aware that in the face of doubt and insecurity, people will have to rely on our calculations”, says Humbert. “Day-to-day, however, one tends not to think about it too much.”
Day-to-day, to the 50-year-old scientist, involves computer work and analyzing massive amounts of satellite data. Approximately 16 million square kilometers of the surface of the Earth – an area almost the size of Russia – are covered in ice. While her research area covers a mere fraction, analyzing 10,000 square kilometers based on topographical images can take years. The better the image, the better the result. The available data originate from commercial as well as scientific satellites. High-resolution images covering an area of 25 square kilometers can easily cost 4,000 Euros. “Sometimes, when we receive really good images, we do celebrate with a shot of whiskey”, reveals Humbert. Whereas conventional photographs are often used to interpret shadows, premium images offer clear views to the bottoms of the ice lakes – which, according to Humbert, makes a huge difference to the work.
Computer-based glacial research
“Contrary to common belief about polar researchers, I am not much involved in expeditions to the Arctic regions”, says Humbert. Due to the COVID-19 pandemic, two planned expeditions had to be cancelled. “The only expedition left to me this year is my commute on the train from Darmstadt, where I live with my family, to the AWI in Bremerhaven”, says Humbert and laughs.
Fascination from the very beginning
With polar research being her dream job, Humbert has no problem with the many hours of commuting. Following her studies of physics in Darmstadt, it was purely by chance that she became involved in glaciology. During her maternity leave, in her mid-twenties, she began reading the literature on the topic which she had touched on briefly during her studies – and she was hooked. “Ice fascinates me to this day”, says Humbert. “If you think about how much ice there is on Earth, how important the ice is to our Earth, and how little we really know about it – I could not imagine a more fascinating area of research.” The Geoscience students at the University of Bremen agree. Humbert, professor of ice modeling at the university, passes her knowledge and her experience on to the next generation. She is pleased: the students are very engaged, and they come prepared with plenty of prior knowledge. “They don’t need me to talk to them about honey.“
Prof. Dr. Angelika Humbert
Prof. Dr. Angelika Humbert is a glaciologist at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research. Humbert, who holds a PhD in physics, specializes in computer simulation and remote sensing of ice sheets, ice currents and shelf ice. With the help of physical formulae and computer modelling, she aims to depict and predict processes far into the future. She is also Professor for Ice Modelling at the University of Bremen.