December 3, 2025, 3:07 pm | Read time: 3 minutes
Researchers have discovered a previously unknown wave in the depths of Lake Geneva. In summer, it travels around the shore within a few days. Find out exactly what this is all about here.
Most people think they know what a wave on the water looks like. However, not all waves form on the water’s surface. In the depths of a body of water, wave-like currents occur, known as internal waves. A recent study has now discovered a previously unknown type of wave in Lake Geneva.
Wave Caused by Temperature Differences
While boats sail above or swimmers do their laps, the newly discovered wave snakes along the shore underwater. It is strongest at a depth of thirty meters and moves at up to 30 centimeters per second. According to researchers, the wave is not caused by wind but by three shifting temperature layers. In contrast, previously known internal waves involve only two layers.
The emerging so-called V2 Kelvin wave has another unique feature, according to the study. The Coriolis force, caused by Earth’s rotation, gives it an additional spin. As a result, it begins to move counterclockwise along the shore around the lake, always rotating around a fixed point in the lake’s center. The effect was most strongly detected at about 30 meters deep and roughly one kilometer from the shore. “The current created by this is by far the strongest we measured this summer. It ranks among the strongest in the lake overall,” explains Rafael Reiss, the study’s lead author from the University of Cambridge.
What effect does this special type of wave have? According to the study, the movement affects the transport of sediment particles as well as pollutants and nutrients in the coastal area. The underwater wave likely has no direct impact on swimmers, Reiss explains in response to a TRAVELBOOK inquiry. “The strongest currents and vertical movements of the water layers are found at about 25 meters deep, much deeper than where regular swimmers are.” Divers, however, might notice the temperature differences. “However, the wave moves so slowly around the lake that it’s not a dramatic temperature jump but rather a gradual change,” Reiss explains.
Surprising Discovery
The discovery of the underwater wave in Lake Geneva was both surprising and puzzling. It should have been noticed long ago, as the lake is one of the most studied in the world. Reiss concludes that one reason might be that measurements were not taken in the right place.
Placed incorrectly, the probes can only capture one or two of the characteristic layers—not all three that make up the new waveform.
However, researchers are confident that V2 Kelvin waves can also be found in other lakes, particularly those similar in size and depth to Lake Geneva. Lake Constance is considered a strong candidate.