Defusing Africa's Killer Lakes

Crater lakes in the volcanic highlands of Cameroon were responsible for a natural disaster of mass proportions. In 1986 residents along the shore of Lake Nyos died of a mysterious mass asphyxiation, fulfilling ancient geomythological prophesies about this region. The scientists who flocked to the craters determined that gases trapped deep in the waters accumulated and exploded in a lethal emission. A similar incident occurred at a nearby lake in 1984, killing 47. Scientists have concluded that an accumulation of carbon dioxide, kept under pressure from the lake waters, was responsible. The constant temperature of this equatorial lake increased the pressure. The detonation of accumulated carbon dioxide may have occurred through a rockslide, an unexpected drop in air temperature which would cause the surface water to cool or sink, or a strong wind. Vent pipes have been installed to relieve some of the pressure.