Have you ever felt a nuclear explosion taking place in the sky? During stronger, stormy mining processes, it sometimes happens that a cloud in the form of a mushroom cloud appears in the sky.
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This is a special kind of thundercloud, the Cumulonimbus capillatus incus. Cumulonimbus is actually a general term for any thunderstorm cloud, but there are several types with different consequences. The most impressive mushroom-shaped thunderstorms often make headlines in the local media. It even happens that they cause moments of panic among the population, since their shape can be disturbing.
The highest clouds in the world
What makes a single cumulonimbus cloud look so apocalyptic? It is actually the very large anvil that gives this impression of a nuclear catastrophe. The anvil (Latin: incus) is the top of the storm cloud, which extends horizontally for 20 to 50 kilometers when it reaches the tropopause level. The cloud cannot rise any further, its tip then collides with the tropopause and forms a kind of envelope.
It is the anvil (like the forging tool) that peaks between 8 and 15 kilometers in altitude, sometimes as high as 18 kilometers in South American and African thunderstorms. Due to the strong wind that pushes it forward, the shape of the mushroom is often slightly asymmetrical. Formation lasts about 30 minutes, and its development is perfectly visible to the naked eye.
The effect is not only spectacular from the ground, but also from the sky:
The Cumulonimbus capillatus incus is the highest cloud in the world, but also the most dangerous. Indeed, if nothing atomic is contained in the latter, an explosion occurs: this storm cloud, which culminates very high, is enlivened by very violent up and down winds.
These currents therefore have the power to push very heavy precipitation such as heavy rain and hail to the ground. This cloud is justifiably impressive: it portends the impending severe weather with possible flooding and damage from wind, hail and lightning.
Fires and volcanoes can also produce mushroom clouds
Another type of cloud can also take the form of a mushroom cloud, the pyrocumulonimbus: a thundercloud that forms over a source of intense heat, such as a forest fire or volcanic eruption. It’s the same principle as with a classic cumulonimbus: the air becomes saturated, the water vapor condenses into droplets and forms a cloud. Unlike other clouds, the heat source is not heat from the sun, but another intense heat source coming from the ground.
In the final stage of its formation, it can then take the form of a mushroom cloud. It is exactly the same process that takes place in the sky in the event of a real nuclear explosion.