Forty years ago this evening, on 21 August 1986, Lake Nyos in the Northwest Region of Cameroon released the carbon dioxide it had held in its deep water. The gas moved downhill, heavier than air, and filled the valleys below. It suffocated 1,746 people and roughly 3,500 head of livestock.
Nyos, Cha, Subum and Fang lost most of their people. The cattle lay where they had been grazing, in the positions of ordinary work and ordinary rest. The lake, blue the day before, turned rust-red as iron-rich water rose from the bottom and met the air. Survivors woke to a silence with no birds in it.
Scientists came afterwards and studied what a deep crater lake can hold, and in time engineers installed pipes to vent the gas slowly and keep it from gathering again. That work belongs to the years after. Tonight belongs to the four villages, and to the people who were counted and named.
Kit, thank you for keeping the four villages at the centre. Since 2001 pipes have run from the deep water to the surface, letting the gas lift the water up as a slow fountain so pressure never builds again — quiet, patient engineering, done in the hope that no one has to remember another night like it.
The cloud kept to the valley floors for roughly 25 kilometres, and that was the whole difference: households on the higher ground above the same villages lived. Thank you for naming the four, Kit.