Mushroom clouds?

Question

What is it exactly that causes a mushroom shaped cloud after a nuclear explosion?
Water being rapidly vaporized?

Answer 1

The cloud is a mix of dust and nitrogen dioxide; a brown gas produced when the oxygen and nitrogen in air are heated to high temperature. The rising column of air is vertical as it rises through the troposphere. When it reaches the tropopause, the boundary with the stratosphere, at a height of about 35000 feet. it spreads out like a mushroom head. This is because the tropopause is a temperature inversion. The stratosphere acts like a lid on warm, rising air. That's one of the reasons most airliners fly at about 40000 feet. There's little turbulence, cloud or weather in the stratosphere.

Answer 2

It's not just nukes; any large explosion causes a mushroom cloud. When the blast occurs, a pressure wave expands outward and then collapses back in. This returning pressure pushes the dust, debris, and smoke back in toward "ground zero." All that stuff then goes the only way it can- up. As gravity takes over, the debris mushrooms out and down, creating the distinctive cloud.

Answer 3

The explosion products are initially very hot, and rise rapidly. As they rise, they are cooled both by expansion and by mixing with the surrounding atmosphere, and cooler gases are denser. Eventually, the cloud gets high enough that its density is the same as the surrounding air, so it can rise no higher. Since it can't go up, it goes out, giving the familiar shape.

Answer 4

the extreme happiness that it gives to everyone, mushroom clouds the gift that just keeps giving.

Answer 5

the air gets really, really, hot there...then the process of convection and entrainment takes over. Of course, it's so visible because of the dirt and other debris that it picks up.

Answer 6

They appear because of the air pressure differences or something... I read about it a LONG time ago.