internal seich

Internal seiches are oscillations that occur within a lake's layers of different densities, typically caused by thermal stratification. These layers, separated by a thermocline, move relative to each other. This movement is important because it can lead to significant water exchanges and turbulence, periodically exposing different parts of the lake bottom to varying water conditions. Unlike surface waves, internal seiches are much slower due to the smaller density differences between water layers. They can be observed in various lakes, with periods ranging from hours to days, depending on the lake's characteristics.12