“A hotel with sensors” very valuable for understanding the impact of global warming

The Tour de France stops in Switzerland this weekend, with an arrival in Lausanne on Saturday July 9. On Sunday, the runners will go around Lake Geneva: the largest lake in Western Europe is of great interest to some scientists who have set up a floating laboratory off Lausanne.

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To access this laboratory, Sébastien Hallier embarked with Sébastien Levanchy, the technical manager of the platform for a trip of a few minutes by boat. “The LéXplore platform is 600 meters offshore, it’s a wonderful day for a Zodiac ride“, comments Sébastien Levanchy. The sun is indeed there and for the scientists, the study of Lake Geneva deserves to move away from the shore. “We are here in a very deep lake, testifies Marie-Élodie Pergawhich is more than 300 meters deep, so what happens on the coast is not very representative of the processes that take place in open water.“

The scientific platform, surrounded by orange buoys, floats peacefully on the waters of Lake Geneva. Researchers have installed a multitude of computers and instruments of all kinds. Sensors and probes place the lake under surveillance 24 hours a day.

“For years, the way to sample the waters of a lake was to take a boat and take samples from one place or another…”

Marie-Elodie Perga

at franceinfo

For the scientist, this platform allows both to be “a hotel with sensors” and also makes it possible to be able to directly process the samples, from LeXplore, by bringing machines directly to Lake Geneva.

On the platform, 48 temperature sensors, hydrophones, in other words microphones that go under water. Enough to collect a lot of data and better understand what is happening in the lake, in particular on the mixing of the waters. An essential process for the oxygenation of the waters of the lake but disrupted by global warming. “We are increasingly under the threat of seeing the arrival of periods of deoxygenation of the lake“, regrets Marie-Élodie Perga. Despite everything, the scientist wants to be optimistic: “SIf we continue to control the levels of phosphates that come into the lake, we can manage to buffer the harmful consequences of climate change.“

From the carbon cycle, to the invasion of the quagga mussel or even the concentrations of microplastics in the waters of Lake Geneva, this platform makes it possible to supply some forty research projects.