“I realized that, in Switzerland, you don't give students a zero!"

When we spoke with Alexis Berne, who heads EPFL’s Environmental Remote Sensing Laboratory (LTE), he was getting ready to leave on a three-month expedition to the Antarctic. Is it a problem to leave his students for such a long stretch? “It certainly poses challenges,” he says. “I had to be creative and change the order in which I teach things. I covered the most essential topics at the start of the semester and arranged my trip so that I’ll be back in time to grade the exams.” Teaching assistants and postdocs will supervise the students’ hands-on projects while he’s gone. “It’s another reminder of how important it is to build of team of people you can count on, whether for research or teaching,” he says.

From hot to cold, and then glacial

It’s easy to picture Berne as a young boy spending entire afternoons watching documentaries on penguins and melting glaciers. Yet his interest in polar regions actually came much later. He discovered what would become his main research area – precipitation – in a much more temperate climate. “I completed my senior-year project for my engineering degree in Marseille, working for the city’s technical experts to investigate rainfall patterns in Mediterranean areas,” says Berne. Until then, he wasn’t sure what he wanted to do. “That was when I found my calling,” he says.

Berne therefore decided to obtain a master’s degree, followed by a PhD on the hydrology of urban areas – in this case Marseille. “Back then I was already using weather radars for my research,” says Berne. He subsequently completed a postdoc at Wageningen University in the Netherlands, and then joined EPFL in 2006.

“Precipitation is still my main focus area, but I switched from the warm Mediterranean climate to a cold one, and then a polar one!” says Berne. When he first started at EPFL, he continued his work on Mediterranean regions, “but since the School is located in Switzerland, I naturally oriented my research towards the Alps.” Drawing on his expertise in using weather radars in demanding environments, Berne began studying the Antarctic around ten years ago.

In parallel to this work on polar regions, Berne’s research group is continuing to investigate precipitation dynamics in the Alps, as these insights are crucial for forecasting the area’s water resources and natural risks. “We work very closely with the Swiss Federal Office of Meteorology and Climatology,” says Berne. For instance, engineers at LTE are helping to develop algorithms for processing radar data. Some of these algorithms have been incorporated into the MeteoSwiss app for the general public. “We’ve also helped MeteoSwiss track intense weather events, like severe hailstorms,” he says.

Liking by doing

The underlying features of Berne’s research – protecting the environment, learning about water resources and exploring new technology – were already things he was interested in as a teenager. But that’s not quite true for his love of teaching. “I can’t really say teaching was a vocation – it was one of my job requirements when I joined EPFL. But my interest grew as I gave more and more classes,” he says.

Berne smiles as he recalls the first course he taught, back in 2007, on the topic of geostatistics. “I had to adjust the course curriculum during the semester because I saw it was much too complicated for the students.” He also had to change the way he graded exams. “After the first few exam sessions I realized that, here in Switzerland, you don’t give students a zero.”

Changing the pace

Such teaching missteps are now a thing of the past. Berne has since learned that “instead of trying to pack a lot of material into their lectures, as teachers often do,” it’s better to focus on a handful of key topics, go slowly, repeat things when needed and, especially, leave enough time to answer students’ questions. The goal is “to prevent students from disengaging.” Berne continues: “Teachers aren’t there for the good students – they’re there for the other ones. I’m lucky to have always taught mandatory classes, because this means there are always some students in the room who aren’t really interested. I’ve had to learn how to teach people like them.”

But streamlining the class material doesn’t mean making it simpler. “I like to dive deep into subjects, sometimes even more than necessary. After all, EPFL is an institute of technology!” The trick to teaching – “especially when it comes to today’s short-attention-span generation” – is to strike the right balance between describing things in detail and mixing things up to keep students’ attention. “A more experienced professor suggested I use quizzes. Now, once or twice during the 45-minute period, I’m the one who asks the questions.” This method doesn’t just change the pace and reignite the students’ brain cells – it also lets Berne “drive home specific concepts.”

Making it work for everyone

Over the years, Berne has figured out how to interpret teacher evaluations. “Deciphering students’ feedback is a skill!” he says. “You know right away when students aren’t happy, although you have to be able to look past the harshest comments, as they don’t really help you improve.” Berne attributes his best teacher award to the fact that he’s fully invested in what he does. “I guess my students sense that I’m happy to be teaching and that I’m trying to do it in a way that works for everyone.”