A tsunami forms when a wave transfers the energy it receives from its source across a distance and then reaches the shore. While most people associate tsunamis with oceans, they can also occur in rivers, including the Moscow River. This piece presents a broad view of how river waves develop and why some rivers can experience dramatic surges of water.
River tsunamis are often linked to landslides that fall into the water, but powerful ships moving at high speeds can also generate such waves. When a blockage or sudden change at the riverbed occurs, the energy from the disturbance can propagate along the water, creating a large, traveling wave that travels downstream and mirrors the dynamics seen on much larger coastlines.
Experts explain that underwater landslides can unleash tsunamis that are difficult to predict unless the riverbed’s entire structure and potential triggering events are understood. The risk depends on how the bottom is arranged, how sediments shift, and how slopes respond to disturbances. Even when the trigger is not a landslide, altered river flows or rapid vessel movements can initiate significant waves. In the study of river dynamics, researchers note that causes of river tsunamis are not limited to natural events; man made disturbances can play a role as well.
Historical records show that landslide tsunamis have occurred in rivers before. In 1597 the Volga region near Nizhny Novgorod reported a landslide that released huge waves as a monastery slid into the river, an event noted in archival annals. More recently, large river waves were observed on the Bureya River in the Far East after a landslide in 2018. These instances demonstrate that tsunamis are not exclusive to seas and oceans; they can arise in rivers with steep banks and significant mass movement. In the far north, a dramatic event occurred in Lituya Bay in 1958 when a massive slide of earth, stones, and ice produced a towering wave that dramatically altered the shoreline.
Studies of deadly waves emphasize how difficult they can be to forecast and how weather conditions can influence their likelihood in coastal regions and inland waterways alike. The discussion extends to river systems in various places, including analyses that consider how atmospheric patterns interact with river dynamics and the potential for rapid surge events near populated areas and industrial sites.