A limnic eruption, which is sometimes known as a lake overturn, is a rare but deadly type of natural disaster that occurs when large amounts of dissolved carbon dioxide erupt from deep lake waters, suffocating livestock, humans, wildlife and anything on its path. It does not involve any fire, lava, smoke or even ash. It is just a tremendous discharge of carbon dioxide.
Although indirectly related, scientists have established that limnic eruptions are very different from volcanic eruptions. While it is true that carbonation can trigger the onset of limnic eruption, cataclysmic events can initiate it as well. In this respect, rainstorms, volcanic eruptions, explosions and wind may all play a part in causing a limnic eruption.
In two instances, which both occurred in Cameroon, a limnic eruption killed 37 people and another 1,800 in 1984 and 1986 respectively. It is believed that the high-pressure of the lakes where it occurred and the tropical nature of the region both played a role in this. Both lakes have the same characteristics in that they are both very deep. The stable nature of the lake due to its deepness allowed the gas to build up within the sediment at the bottom and eventually erupt in a devastating fashion.