Nature's Gas Chamber
Other natural disasters can destroy whole towns at once too. Besides malaria, venomous snakes and leopards, the forest of Cameroon is also home to a lake that kills villages with its belches.
Lake Nyos released an estimated 1.2 cubic kilometers (0.29 cu. mi.) of carbon dioxide and noxious sulfurous gases on August 21, 1986. As the bubble of heavier-than-air gas spread along the ground, approximately 1,700 people were suffocated along with 3,500 livestock. The killing cloud spread death up to 25 km (16 mi) from the lake.
The lake's gas problem comes from an underwater magma dome that is constantly leaking carbon dioxide into the water. As the concentration builds, a disturbance in the lake's waters can cause the gas to be released in a suffocating explosion. Now, a degassing system siphon's the gas saturated deeper waters up to the surface, where the gas escapes in harmless quantities.
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