n
n
n
n– 1986
n
n
n
n
n
nAllnmy life I have heard of volcanoes erupting…but I didn’t know thatnlakes could erupt!
n
n
n
n
n
nLakenNyos, in the African nation of Cameroon, is a crater lake that liesnon the side of an inactive volcano. It is saturated with carbonndioxide, which seeps up from a magma chamber below the lake. Usuallynthe carbon dioxide stays dissolved in the bottom layers of the lakenwater, but over time the water becomes supersaturated.
n
n
n
n
n
nWhennthe lake is supersaturated with CO2, and an earthquake or landslidenoccurs, a lot of the carbon dioxide can suddenly come out of solutionnand erupt from the lake, overflowing the water’s edge and pouringndown valleys, suffocating animals and people.
n
n
n
n
n
Thisnis called a limnic eruption, and we only know of two such events. (Wenonly know of three lakes in the whole world that are saturated withnCO2 saturation—and they’re all in Africa!) In 1984 anothernsupersaturated lake in Cameroon suddenly outgassed carbon dioxide,nkilling 37 people. This 1986 overturn of Lake Nyos was far morentragic: 1.6 million metric tons of CO2 were suddenly released in ancloud that rose at a speed of nearly 100 kilometers per hour (62mph).nA fountain of water and foam 91 meters (300 feet) high formed at thensurface of the lake, and a wave at least 24 meters (80 feet) highnwashed the lake’s shores. The gas flowed down several valleys—beingnheavier than air, it hugged the ground—and killed around 1,700npeople!
Thisnis called a limnic eruption, and we only know of two such events. (Wenonly know of three lakes in the whole world that are saturated withnCO2 saturation—and they’re all in Africa!) In 1984 anothernsupersaturated lake in Cameroon suddenly outgassed carbon dioxide,nkilling 37 people. This 1986 overturn of Lake Nyos was far morentragic: 1.6 million metric tons of CO2 were suddenly released in ancloud that rose at a speed of nearly 100 kilometers per hour (62mph).nA fountain of water and foam 91 meters (300 feet) high formed at thensurface of the lake, and a wave at least 24 meters (80 feet) highnwashed the lake’s shores. The gas flowed down several valleys—beingnheavier than air, it hugged the ground—and killed around 1,700npeople!n
n
n
n
n
nScientistsnaren’t even sure what triggered the eruption of Lake Nyos. It maynhave been a landslide, a small earthquake, or even a small volcanicneruption on the bed of the lake. However, witnesses did not feel anyntremors on the morning of the disaster.
n
n
n
n
n
nWhateverntriggered the limnic eruption, the normally blue waters of the lakenturned deep red (because iron-rich water from the deep rose to thensurface and were oxidized by the air), the level of the lake droppednby about one meter (3 feet), and trees near the lake were knockedndown!
n
n
n
n
n
nScientistsnare trying to prevent another such disaster by degassing the lake.nSome French scientists have installed degassing columns; they pumpnwater from the bottom of the lake until the loss of pressure beginsnto release the gas and makes the process self-powered.
n
n
n
n
n
n
n
n
n
nAlsonon this date:
n
n
n
n
n
n
Anniversary of the theft of the Mona Lisa
Anniversary of the theft of the Mona Lisan
n
n
n
n
n
n
n
n
n
n
n
n
n
n
n
n
n
n
n
nAnniversary of the Voyager 2 fly-by of Triton
n
n
n
n
n
n
n
n
n
n