Michael Davis
Mushroom clouds are the result of a massive release of heat from a large explosion. They are best known for their appearance after nuclear detonations, but they can be created by any explosion of sufficient heat and magnitude. The height reached by the cloud depends on the heat energy of the explosion and the atmospheric conditions. The mushroom shape is formed as the fireball rises, cools, and flattens, with the top part of the cloud becoming rounded like the cap of a mushroom. The bottom part of the cloud forms a stem as dirt and debris are sucked up by the explosion.
| Characteristics | Values |
|---|---|
| Formation | The sudden formation of a large volume of lower-density gases at any altitude, causing a Rayleigh–Taylor instability |
| Shape | The upward movement of the buoyant mass of gas creates turbulent vortices curling downward around its edges, forming a temporary vortex ring that draws up a central column, possibly with smoke, debris, condensed water vapour, or a combination |
| Height | The height reached by the cloud depends on the heat energy of the weapon and the atmospheric conditions. If the cloud reaches the tropopause, it will spread out, but if there is sufficient energy remaining, a portion will ascend into the stratosphere |
| Color | Initially red or reddish-brown due to the presence of nitrous acid and oxides of nitrogen; changes to white due to water droplets |
| Visibility | The cloud may be visible for about an hour before being dispersed by the wind |
| Natural occurrence | Mushroom clouds can also be produced by some volcanic eruptions and impact events |
Explore related products
What You'll Learn
- A massive release of heat and energy from an explosive fireball
- The formation of a vacuum, which is filled with smoke and debris
- Rayleigh-Taylor instability, where low-density gases rise rapidly, forming a vortex ring
- The presence of nitrous acid and oxides of nitrogen, causing a reddish-brown colour
- The height of the explosion, which affects the shape of the resulting mushroom cloud
A massive release of heat and energy from an explosive fireball
A mushroom cloud is the result of a massive release of heat and energy from an explosive fireball. When a bomb explodes, energy is released in all directions. The fireball increases in size and rises through the atmosphere, creating a vacuum as it moves upwards. This vacuum is immediately filled with smoke and debris, forming the visible central column of what will become the mushroom cloud.
The fireball continues to rise until it reaches a point in the atmosphere where the air is cold and dense enough to slow and flatten it. The cloud continues to rise as it flattens, forming the rounded cap of the mushroom. The height reached by the cloud depends on the heat energy of the explosion and the atmospheric conditions. If the cloud reaches the tropopause, it will spread out. However, if there is sufficient energy remaining, a portion of the cloud will ascend into the stratosphere.
The formation of a mushroom cloud is not unique to nuclear explosions. Any explosion with sufficient heat and energy will create a similar effect. For example, powerful conventional weapons, such as thermobaric weapons, can produce mushroom clouds. Additionally, natural events like volcanic eruptions and impact events can also generate mushroom clouds.
The distinctive shape of the mushroom cloud is due to the Rayleigh-Taylor instability, which occurs when a large volume of lower-density gases is suddenly formed at any altitude. The buoyant mass of gas rises rapidly, creating turbulent vortices that curl downward around its edges. This forms a temporary vortex ring that draws up a central column, which can include smoke, debris, condensed water vapour, or a combination of these elements.
The colour of the mushroom cloud is initially red or reddish-brown due to the presence of nitrous acid and oxides of nitrogen. As the fireball cools and condensation occurs, the colour changes to white, mainly due to the formation of water droplets, similar to an ordinary cloud.
Drying Lobster Mushrooms: A Step-by-Step Guide
You may want to see also
The formation of a vacuum, which is filled with smoke and debris
A mushroom cloud is the result of a large explosion, often associated with nuclear detonations. However, any explosion with sufficient heat and magnitude can produce a similar effect. When a bomb explodes, energy is released in all directions. As the fireball expands, it rises due to convection, creating a vacuum in its wake. This vacuum is immediately filled with smoke and debris, forming the central column of what will become the mushroom cloud. The fireball continues to rise and cool, and as it reaches higher altitudes, the surrounding air becomes colder and denser, slowing its ascent. This causes the fireball and its smoke trail to flatten, forming the rounded cap of the mushroom. The cloud continues to rise and spread laterally, growing into the characteristic mushroom shape.
The formation of the mushroom cloud's stem and cap depends on the height of the explosion. If the bomb is detonated high enough, the stem and cap may not meet, resulting in a gap between the two. In contrast, explosions closer to the ground can produce a more classic mushroom profile, where the stem and cap merge. Additionally, the height of the explosion affects the amount of dirt and debris sucked into the cloud. Surface bursts or explosions near the ground can result in larger amounts of dirt, dust, and debris being drawn into the cloud, contributing to the stem's formation.
The colour of the mushroom cloud also provides information about the explosion. Initially, the cloud is reddish-brown due to the presence of nitrous acid and oxides of nitrogen. As the fireball cools and condensation occurs, the colour changes to white, primarily due to the formation of water droplets, similar to those in ordinary clouds. The height reached by the cloud depends on the heat energy of the explosion and atmospheric conditions. If the cloud reaches the tropopause, it tends to spread out. However, if it still retains sufficient energy, a portion may ascend into the more stable air of the stratosphere.
The mushroom cloud continues to grow and spread laterally, and it may remain visible for about an hour or more before being dispersed by the winds and merging with natural clouds in the sky. The duration and visibility of the cloud are influenced by weather conditions. While mushroom clouds are often associated with nuclear explosions, they can also occur naturally through powerful volcanic eruptions or impact events.
Maitake Mushrooms: Gluten-Free Superfood?
You may want to see also
Rayleigh-Taylor instability, where low-density gases rise rapidly, forming a vortex ring
Mushroom clouds are the result of large explosions, most famously nuclear detonations. They can, however, be caused by powerful conventional weapons or natural events such as volcanic eruptions. The explosion creates a large volume of low-density gases at any altitude, causing a Rayleigh-Taylor instability.
The Rayleigh-Taylor instability occurs when there is a difference in fluid densities, with the less dense fluid accelerating into the denser fluid. This can be seen in the formation of mushroom clouds as the buoyant mass of low-density gas rises rapidly, forming turbulent vortices that curl downwards around its edges. This is the beginning of the formation of the ubiquitous mushroom shape.
As the fireball rises, it forms an inverted cup shape, causing turbulence and a vortex that sucks more air into its centre, creating external afterwinds and further cooling the fireball. This vortex forms a temporary vortex ring, drawing up a central column of smoke, debris, condensed water vapour, or a combination of these, to form the ""mushroom stem". The vortex ring is a key feature of the Rayleigh-Taylor instability, where the heavier fluid falls through the lighter fluid and rolls up, forming a vortex ring.
The mushroom cloud continues to rise and cool, and its buoyancy decreases, slowing its ascent. The cloud may reach the tropopause, where it tends to spread out. If the cloud has sufficient energy at this height, a portion of it will ascend into the stratosphere, reaching its maximum height in around 10 minutes. The cloud continues to grow laterally, forming the characteristic mushroom shape. The cloud may remain visible for an hour or more before being dispersed by the wind, merging with natural clouds in the sky.
Reishi Mushrooms: Medicine or Myth?
You may want to see also
Explore related products
$20.74 $29.99
![[( The National Audubon Society Field Guide to North American Mushrooms )] [by: Gary A. Lincoff] [Jun-1988]](https://m.media-amazon.com/images/I/41gbHvaEChL._AC_UY218_.jpg)
![[2 Pack] Photo Fog Atmosphere Spray Made in the USA for Photographers & Filmmakers - Safe Fog Machine Alternative - Smoke in a Can - Haze in a Can - Smoke Bombs for Photography - 8oz Fog Spray Cans](https://m.media-amazon.com/images/I/71I19jmFe2L._AC_UL320_.jpg)
The presence of nitrous acid and oxides of nitrogen, causing a reddish-brown colour
The presence of nitrous acid and oxides of nitrogen, particularly nitrogen dioxide, is responsible for the reddish-brown colour of mushroom clouds formed by bomb explosions. This colour is a result of the preferential absorption of light in the blue region of the spectrum (400-500 nm) by nitrogen dioxide. The reddish-brown colour is also observed in smog, which is caused by nitrogen dioxide in combination with aerosols.
Nitrogen dioxide is a reddish-brown gas that is poisonous and can be fatal if inhaled in large quantities. It has a pungent, acrid odour above 21.2 °C (70.2 °F; 294.3 K) and becomes a yellowish-brown liquid below this temperature. Nitrogen dioxide is one of several nitrogen oxides, which are formed through the oxidation of ammonia via the Ostwald Process. This process is used in the industrial production of nitric acid, which is then used to make fertilizers.
The reddish-brown colour of the mushroom cloud is only temporary and changes to white as the fireball cools and condensation occurs. This colour change is due to the formation of water droplets, similar to those in an ordinary cloud. The height reached by the radioactive cloud depends on the heat energy of the weapon and atmospheric conditions. If the cloud reaches the tropopause, it tends to spread out, but if it has sufficient energy, a portion of it will ascend into the stratosphere, where it stabilizes and continues to grow laterally, forming the characteristic mushroom shape.
The formation of a mushroom cloud is the result of a large volume of lower-density gases being formed suddenly at any altitude, causing a Rayleigh-Taylor instability. The buoyant mass of gas rises rapidly, creating turbulent vortices that curl downward around its edges, forming a temporary vortex ring that draws up a central column. This upward motion creates a vacuum that sucks in dirt and debris, forming the stem of the mushroom cloud.
Nuclear mushroom clouds are often accompanied by short-lived vapour clouds known as Wilson clouds, condensation clouds, or vapour rings. These clouds are caused by a sudden rarefaction of the surrounding medium, leading to a drop in temperature and the condensation of moisture in the air surrounding the explosion.
Mushroom Toxins: Which Varieties Cause Orellanus Syndrome?
You may want to see also
The height of the explosion, which affects the shape of the resulting mushroom cloud
The height of a bomb explosion determines the shape of the resulting mushroom cloud. The height of the explosion affects the amount of dirt and debris that gets sucked into the cloud. When a bomb explodes, energy is released in all directions, creating a fireball of hot gases. The height of the explosion determines how much dirt and debris is sucked into the fireball, which then cools and condenses to form the mushroom cloud.
If the explosion occurs high above the ground, the resulting cloud will have less dirt and debris and will be lighter in colour. The stem and cap of the mushroom cloud may not meet, as seen in the explosions over Hiroshima and Nagasaki. These explosions occurred at a height of nearly 2,000 feet (610 meters) above ground. The mushroom clouds produced by these explosions had a distinct white cloud and a brown stem below, but the two parts did not meet.
On the other hand, if the explosion occurs closer to the ground, more dirt and debris will be sucked into the cloud, resulting in a darker mushroom cloud. In this case, the stem and cap of the mushroom cloud are more likely to merge, forming the classic mushroom profile.
The height of the explosion also affects the maximum height reached by the mushroom cloud. The cloud continues to rise until it reaches an equilibrium level, at which point it stops ascending and begins to flatten into the characteristic mushroom shape. The eventual height of the cloud depends on the heat energy of the weapon and atmospheric conditions. If the cloud reaches the tropopause, it tends to spread out instead of continuing to rise.
Additionally, the height of the explosion can influence the formation of condensation rings and bells around the stem of the mushroom cloud. Higher-yield explosions create intense updrafts, which, combined with the associated drop in pressure and temperature, lead to the formation of skirts and bells. The layering of humidity in the atmosphere also influences the shape of the condensation artifacts along the stem.
Creating Mushroom Spawn: A Step-by-Step Guide
You may want to see also
Frequently asked questions
A mushroom cloud is formed by a massive release of heat and energy from an explosion, which creates a vacuum as it moves rapidly through the atmosphere. This vacuum is immediately filled with smoke and debris, forming the visible central column of what will become the mushroom cloud. The fireball rises and cools, causing vapours to condense into a cloud containing solid particles of weapon debris and small drops of water. The cloud continues to rise and flatten, forming the rounded cap of the mushroom.
A mushroom cloud is a mushroom-shaped cloud of debris, smoke and condensed water vapour. When a bomb explodes, the fireball is made up of vapourised products of the bomb itself and water condensed from the surrounding air.
Any explosion of sufficient heat and magnitude will create a mushroom cloud, but they are most commonly associated with nuclear explosions. Nuclear bombs create very hot gas, and as this rises, it is displaced by denser, cooler gases. This forms a torus or doughnut shape, with a jet of material being sucked into the vacuum, which pushes upwards to form the mushroom cloud.
