Limnic eruption

Scientists believe earthquakes, volcanic activity, and other explosive events can serve as triggers for limnic eruptions as the rising CO2 displaces water.

[4] The first recorded limnic eruption occurred in Cameroon at Lake Monoun in 1984, causing asphyxiation and death of 37 people living nearby.

[5] A second, deadlier eruption happened at neighboring Lake Nyos in 1986, releasing over 80 million m3 of CO2, killing around 1,700 people and 3,000 livestock, again by asphyxiation.

Among the victims are perfectly preserved insects, frogs, turtles, crocodiles, birds, anteaters, insectivores, early primates, and paleotheres.

[11] Regardless of cause, the trigger pushes gas-saturated water higher in the lake, where the reduced pressure is insufficient to keep gas in solution.

Second, the vast majority of lakes are holomictic (their layers mix regularly), preventing a buildup of dissolved gases.

At Lake Nyos, the gas cloud descended into a nearby village where it settled, killing nearly everyone; casualties as far as 25 km (16 mi) were reported.

[citation needed] A change in skin color on some bodies led scientists to hypothesize the gas cloud may have contained dissolved acid such as hydrogen chloride, though this hypothesis is disputed.

The deep lake waters are slightly acidic due to the dissolved CO2 which causes corrosion to the pipes and electronics, necessitating ongoing maintenance.

There is some concern that CO2 from the pipes could settle on the surface of the lake forming a thin layer of unbreathable air and thus potentially causing problems for wildlife.

[17][18] These three pipes are thought to be sufficient to prevent an increase in CO2 levels, removing approximately the same amount of gas that naturally enters at the lake bed.

The part within the Democratic Republic of the Congo is a site of active armed conflict and low state capacity for the DRC government, which impedes both studies and any subsequent mitigating actions.

[21] Two significant changes in Lake Kivu's physical state have brought attention to a possible limnic eruption: the high rates of methane dissociation and a rising surface temperature.

[citation needed] A scheme initiated in 2010 to use methane trapped in the lake as a fuel source to generate electricity in Rwanda has led to a degree of CO2 degassing.

[24] During the procedure for extracting the flammable methane gas used to fuel power stations on the shore, some CO2 is removed in a process known as catalyst scrubbing.