Making History Come Alive Newsletter The tragic event occurred on August 21, 1986, at Lake Nyos, a crater lake in the Northwest Region of Cameroon

This natural disaster was caused by a limnic eruption, also known as a "lake overturn," which released a large cloud of carbon dioxide (CO2) gas from the lake, suffocating approximately 1,746 people and over 3,500 livestock in nearby villages.

Key aspects of the Lake Nyos disaster include:

1. Limnic Eruption: A limnic eruption is a rare natural phenomenon where dissolved CO2 in a lake suddenly erupts, releasing the gas into the atmosphere. In the case of Lake Nyos, CO2 had accumulated in the lake's depths from volcanic activity beneath the lake bed. The release was triggered by a disturbance, possibly a landslide or a change in water temperature.

2. Impact: The CO2 cloud, being heavier than air, flowed down the valleys surrounding the lake and displaced the oxygen in the air. This caused asphyxiation in people and animals within a 25-kilometer radius of the lake, as they were unable to breathe the CO2-laden air.

3. Response and Investigation: The disaster prompted scientific investigations to understand the cause and prevent future occurrences. Researchers determined that the CO2 buildup in the lake was due to volcanic activity and identified other lakes in the region with similar risks.

4. Mitigation Efforts: To prevent future disasters, degassing efforts were implemented at Lake Nyos and nearby Lake Monoun (which experienced a similar, smaller-scale event in 1984). Pipes were installed to help release the CO2 from the bottom of the lakes in a controlled manner, reducing the risk of another sudden gas release.

5. Lessons Learned: The Lake Nyos disaster highlighted the need for geological and environmental monitoring in regions with volcanic activity. It also underscored the importance of community awareness and preparedness for natural disasters.

Overall, the Lake Nyos tragedy remains one of the deadliest natural CO2 emissions in recorded history, and it has led to increased understanding and preventive measures for similar phenomena worldwide.