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Lake Nyos Suffocates 1,746 People With Carbon Dioxide · Chronopin

DisasterPosted 09/21/202609/21/2026 at 8:57 pm·@ScienceDesk To timeline

Lake Nyos Suffocates 1,746 People With Carbon Dioxide

Starts 08/21/1986

Lake Nyos, Northwest Region, Cameroon

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Cameroon
Carbon Dioxide
Degassing
Lake Nyos
Limnic Eruption

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The source^[1] opens with the date and the toll: "On 21 August 1986, a limnic eruption at Lake Nyos in northwestern Cameroon killed 1,746 people and 3,500 livestock." No hour is given, so the pin is all-day.

Start: Aug 21, 198690% CONFIDENCEfrom the source

Lake Nyos Suffocates 1,746 People With Carbon Dioxide

A limnic eruption released 100,000-300,000 tonnes of carbon dioxide from a crater lake in northwestern Cameroon. Heavier than air, the cloud rolled downhill and suffocated everyone and everything within 25 km.

The limnic eruption of 21 August 1986 killed 1,746 people and 3,500 livestock. [S]
It released about 100,000-300,000 tonnes of carbon dioxide, which rose at nearly 100 km/h and then, being heavier than air, descended onto nearby villages. [S]
People and livestock were suffocated within 25 km of the lake. [S]
A degassing system has since been installed to lower the dissolved CO2 and the risk of a repeat. [S]
With the Lake Monoun disaster two years earlier, it is one of only two recorded limnic eruptions in modern history. [S]
The Smithsonian records Lake Nyos within the Oku Volcanic Field. [1]

0

References 289% CONFIDENCE

The first entry is always the pin's source. Overall confidence is a weighted average of how firmly each reference supports the start and end times used above; a reference counts half as much for every 180 days older than the newest.

[1]90%
en.wikipedia.org/wiki/Lake_Nyos_disaster
en.wikipedia.org· Posted Sep 21, 2026· Starts Aug 21, 1986 ✓· 50% of score
The source opens with the date and the toll: "On 21 August 1986, a limnic eruption at Lake Nyos in northwestern Cameroon killed 1,746 people and 3,500 livestock." No hour is given, so the pin is all-day.
[2]88%
Global Volcanism Program | Oku Volcanic Field
volcano.si.edu· Added Sep 21, 2026· 50% of score
The Smithsonian's database places Lake Nyos in the Oku Volcanic Field, which is the volcanic system behind the gas release.^[1]

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1Lake Nyos Suffocates 1,746 People With Carbon Dioxide

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