The science behind the disaster is fairly simple. Lake Nyos is a deep pool of water sitting in the throat of a dormant volcano. The real culprit is a pool of hot magma, lying almost 50 miles below the lake. The magma releases the carbon dioxide and other gases, which travel upward through the earth. The gases gets trapped in natural spring water, which eventually rises toward the surface and feed into the crater lake.

The carbon dioxide, instead of being harmlessly released into the atmosphere, gets trapped in the cold water at the bottom of the lake. The amount of gas that can be dissolved in the water is dependent on water temperature and pressure. The greater the pressure, the more gas that can be trapped. None of this would be particularly hazardous if the water at the bottom of the lake were to regularly rise to the surface, where the gas could be safely released. The problem is that the waters of Lake Nyos, like many tropical lakes, are steady and still, with little annual mixing of the water layers.