Dissolved carbon dioxide is causing eruptions in some African lakes, and the powerful force below the surface is like a ticking time bomb.
Exploding lakes are a very real, if rare, part of natural phenomena. The Earth is host to just three exploding lakes: Lake Monoun, Lake Nyos and Lake Kivu, all of which can be found in Africa. The reason that these lakes have been known to explode is the murky, volcanic involvement with various dreaded greenhouse gases, in particular carbon dioxide, that bubbles beneath the surface.
Here are the three exploding lakes of the world.
Photo Credit: NASA Goddard Space Flight / Flickr.com
Lake Monoun, lies in West Province, Cameroon, in the so-called Oku Volcanic Field. Lake Monoun exploded on Aug. 15, 1984.
A gas cloud reportedly rose from a crater in the eastern part of the exploding lake. 37 residents in a low-lying area were fatally wounded. Survivors said that the white, smoky cloud of gas created by the lake smelled pungent. Vegetation around the eastern part of the lake was crushed by a tsunami the explosion caused.
Wind eventually swept the cloud away. Two of the survivors made it out of the disaster alive due to their raised position. They were inside a large truck, which let them breathe because carbon dioxide is heavier than air, causing it to stay close to the ground.
Further study into the incident and a similar event two years later at Lake Nyos led to the accepted scientific explanation of the CO2 explosion as the cause.
Photo Credit: Frederic Mahe / Wikimedia Commons
Lake Nyos – a crater lake also set in Cameroon, West Africa – is synonymous with another eruption disaster. In Aug. 1986, Lake Nyos fatally wounded 1,700 people with a sudden burst of carbon dioxide. The event was the largest natural event of its type ever.
Scientists believe that carbon dioxide of volcanic origin had been oozing into the exploding lake for quite some time – some even say for centuries before the disaster. The theory goes that some disturbance, such as a landslide into the lake, sparked the gust of deadly gas. To stop a recurrence, a degassing tube that siphons water from the bottom layers of water to the top letting the carbon dioxide leak in safe amounts was fitted in 2001. Two more tubes were installed in 2011.
Unfortunately, however, Lake Nyos is not fully tamed. It still represents a threat because its natural wall is deteriorating. A geological tremor could cause it to collapse, enabling water to surge into downstream villages all the way into Nigeria.
Photo Credit: YAOtieno / Flickr.com
Lake Kivu is one of East Africa’s great lakes. The lake lies between the Congo (Kinshasa) to the west and Rwanda to the east. Set at 4,790 feet (1,460 m) above sea level, Lake Kivu occupies 1,040 square miles (2,700 square km).
The lake bed rests upon a rift valley that is gradually being ripped apart, sparking volcanic activity and making it particularly deep. Its maximum depth of 1,575 ft (480 m) is ranked eighteenth in the world.
Analysis of Lake Kivu’s history shows erratic, yet immense, biological extinction on millennial timescales. Volcanic activity is suspected. Scientists fear that future volcanic interaction with the lake’s basal water, which has high gas concentrations, could heat water, push methane out of it, spark a methane explosion and cause an almost immediate discharge of carbon dioxide. Another threat is that the lake could spawn tsunamis as gases erupt from it.
Because 2 million people live near Kivu, the lake’s gas pressure is under scrutiny. If Kivu blows, the devastation from this natural phenomenon could be on a par with the tsunamis of 2004.