At about 9.30 on August 21, 1986, rumbling sounds lasting 15-20 seconds brought people out of their Cameroon homes in the small village of Nios. Not minutes after, a lethal gas cloud pooled out of nearby Lake Nyos and spread over the town. People reported smelling an odor like rotten eggs or gunpowder, felt a warm feeling, and quickly lost consciousness. Survivors, who woke 6-36 hours, felt disoriented and weak, and found that their friends and family were all dead. About a day later began the grim chore of recovery and burial. It wasn’t until August 24th when two Swiss missionary helicopter (Helimission) pilots flew into the area that the rest of the world heard of the incident.
By the time the Helimission pilots arrived, the lake surface was calm and littered with floating clumps of vegetation, and it had turned from its clear blue color to a rust red. Vegetation damage showed that a water surge had washed up the southern shore to 25 m. A water surge 6 m high had flowed over the spillway at the northern end of the …show more content…
The gas cloud was produced by the rapid exsolution of large amounts of CO2 out of the lake. The gas coming out of the lake resulted in waves, which were also reported being seen by survivors. Since CO2 is denser than ambient air, it increased in density, kind of like how dry ice spills out of a bowl like a cloud. At full saturation, Lake Nyos could hold about 1.5 km3 of CO2. So the lake could have released about 1.2 km3 of CO2 into the air in the gas cloud. This would have caused the lake’s level to drop about 110 cm. The cloud was likely about 100 m to 50 m tall when it poured over the small village of
By the time the Helimission pilots arrived, the lake surface was calm and littered with floating clumps of vegetation, and it had turned from its clear blue color to a rust red. Vegetation damage showed that a water surge had washed up the southern shore to 25 m. A water surge 6 m high had flowed over the spillway at the northern end of the …show more content…
The gas cloud was produced by the rapid exsolution of large amounts of CO2 out of the lake. The gas coming out of the lake resulted in waves, which were also reported being seen by survivors. Since CO2 is denser than ambient air, it increased in density, kind of like how dry ice spills out of a bowl like a cloud. At full saturation, Lake Nyos could hold about 1.5 km3 of CO2. So the lake could have released about 1.2 km3 of CO2 into the air in the gas cloud. This would have caused the lake’s level to drop about 110 cm. The cloud was likely about 100 m to 50 m tall when it poured over the small village of