Limnic eruption

A limnic eruption, also known as a lake overturn, is a very rare type of natural disaster in which dissolved carbon dioxide () suddenly erupts from deep lake waters, forming a gas cloud capable of suffocating wildlife, livestock,and humans. A limnic eruption may also cause tsunami or seiche as the rising displaces water. Scientists believe earthquakes, volcanic activity, and other explosive events can serve as triggers for limnic eruptions. Lakes in which such activity occurs are referred to as limnically active lakes or exploding lakes. Some features of limnically active lakes include: saturated incoming water A cool lake bottom indicating an absence of direct volcanic with lake waters An upper and lower thermal layer with differing saturations Proximity to areas with volcanic activity Investigations of the Lake Monoun and Lake Nyos casualties led scientists to classify limnic eruptions as a distinct type of disaster event, even though they can be indirectly linked to volcanic eruptions. Due to the largely invisible nature of the underlying cause ( gas) behind limnic eruptions, it is difficult to determine to what extent eruptions have occurred in the past. The Roman historian Plutarch reports that in 406 BC, Lake Albano surged over the surrounding hills, despite there being no rain nor tributaries flowing into the lake to account for the rise in water level. The ensuing flood destroyed fields and vineyards before eventually pouring into the sea. This event is thought to have been caused by volcanic gases, trapped in sediment at the bottom of the lake and gradually building up until suddenly releasing, causing the water to overflow. In recent history, this phenomenon has been observed twice. The first recorded limnic eruption occurred in Cameroon at Lake Monoun in 1984, causing asphyxiation and death of 37 people living nearby. A second, deadlier eruption happened at neighboring Lake Nyos in 1986, releasing over 80 million m3 of , killing around 1,700 people and 3,000 livestock, again by asphyxiation.