Disasters at Nyos: overview
In 1986, a tremendous explosion of CO2 from the lake Nyos, West of Cameroon, killed more than 1700 people and livestock up to 25 km away. The dissolved CO2 is seeping from springs beneath the lake and is trapped in deep water by the high hydrostatic pressure. If the CO2 saturation level is reached, bubbles appear and draw a rich mixture of gas and water up. An avalanche process is triggered which results in an explosive over-turn of the whole lake. Since 1990 a French team has carried out a series of tests in an attempt to release the gas slowly through vertical pipes …

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