TORNADO: CHARACTERISTICS, CAUSES, TYPES AND CONSEQUENCES - ENVIRONMENT - 2025

A tornado or whirlwind is a natural event that is characterized by the formation of a kind of air funnel that is produced by the change in speed and direction of the winds, usually during an electrical storm.

The union of a cold air current with a warm one causes different temperatures in a storm, which causes the cold winds to descend to the ground level to compensate for the different temperatures.

Justin1569 at English Wikipedia, via Wikimedia Commons

The speed of the winds of this meteorological phenomenon can reach 400 kilometers per hour and, in general, it can have a travel speed of between 16 and 32 kph. The force of tornadoes can blow people up, destroy buildings, and lift cars.

This natural event can take place at any time of the year; however, it tends to occur more frequently during the spring and summer season.

characteristics

Cloud C

Tornadoes are formed by the presence of the "cumulonimbus cloud", one of the largest types of clouds that have been recorded in the Earth's atmosphere and whose formation occurs between 18 kilometers and 20 kilometers in height. Despite this, the base of the cloud can be located as little as two kilometers above the ground.

These clouds are formed thanks to the presence of air masses with different levels of humidity and temperature; their presence tends to indicate the formation of a storm that could include hail. Tornadoes always start from a cumulonimbus cloud and end on the ground.

Atmospheric pressure

A particular characteristic of tornadoes is the low atmospheric pressure inside the natural event, better known as "the eye." This condition causes an increase in the speed of the winds that make it up, as well as their rotation.

Despite this, the atmospheric pressure in cumulonimbus clouds is high, which causes the winds to move towards areas with lower pressure.

Shape

The vast majority of tornadoes are funnel-shaped, the width of which can be greater than 100 meters. However, there are other ways that tornadoes can manifest themselves.

One of the mildest eddies is waterspouts, which have the appearance of a swirl of dust or dirt on the ground. Furthermore, other meteorological phenomena can take the form of a wedge with a considerably wide diameter and a low height.

Another form adopted by these natural events is that of a rope, characterized by having a great height and being considerably narrow. This form originates mainly when the phenomenon is in its final phase; its winds weaken and its thickness diminishes.

Color

Tornadoes can present different shades depending on the environment where the meteorological phenomenon is formed: if they develop in a dry place, they are usually practically invisible. The only way to know where they are is by noticing the debris you drag across the ground.

On the other hand, tornadoes that kick up some debris are lighter in color; while if they move through the water they can reach blue tones.

Natural events of this type that pick up a lot of debris tend to be dark in color or take on the pigmentation of the objects it absorbs. In addition, the position of the sun also influences the hues that the tornado can acquire.

Causes

Training

The vast majority of the most devastating tornadoes have their origin in supercells, which are storms with winds that maintain a constant rotation. These types of storms are not common: about one in every thousand storms becomes supercells.

Supercells form when a stream of cool air descends to compensate for another stream of hot air that rises, causing a storm. Tornadoes originate when the temperature difference between the two air currents is wide; cold air swirls downward.

The natural phenomenon becomes visible the moment the cold air current reaches the ground and begins to kick up debris and dust. Also, the force of the tornado increases as it gets closer to the ground. This causes the supercell to travel to its place of origin.

At this point, at which the tornado has already formed, the event is capable of causing damage to whatever is in its path, depending on the speed of its winds.

The tornado

The constant movement of the winds of a whirlwind allows both warm and cold air to enter it, which causes an increase in power in a short time. During this process, which can take more than an hour, the greatest amount of damage occurs.

The tornado picks up steam as it advances, until a downdraft of cold air is positioned around it, blocking warm air from entering.

End of tornado

When the cold air stream begins to impede the supply of hot air, the tornado's power source is lost. This causes its vortex to weaken.

At this point, the wind eddy begins to slow down until it turns into a rope-like column of air. Despite weakening at this time, the whirlwinds can also gain strength, causing much more damage in their wake.

The storm that caused the natural event also weakens during this process; this makes it disappear after a short time. However, if a new storm re-forms during this process, the cycle could repeat itself.

Types

Rope

Tornadoes can be caused by two types of storms: those that are supercell and those that are not. One of the tornadoes generated in a supercell storm is the rope storm, which is characterized by being extremely thin and long. Its appearance resembles that of a rope.

It is one of the most common tornadoes. Despite being small, this type of tornado is capable of causing severe damage in its path. It is characteristic of both the initial and final phases of this type of natural events.

Cone or wedge

The main characteristic of this type of tornado is that the point that reaches the ground is narrower than the one that is in contact with the storm itself.

The damage it causes is much greater than that which a rope tornado could generate, due to its larger diameter being capable of dragging more objects in its path. Like the rope whirlwind, this type of natural event is formed in the wake of a supercell storm.

Multivortices

This type of vortex is characterized by the formation of two or more simultaneous wind eddies that belong to a common tornado. The vortices that form alongside the main tornado tend to expand the areas it can reach, also causing significant damage in its path.

satelite

Unlike multivortex tornadoes, satellite-type tornadoes are those that form independent of the main tornado, thus amplifying the impact caused on its surroundings.

This type of natural phenomenon is extremely rare and originates from a supercell storm.

Waterspouts

Waterspouts, better known as "waterspouts", are those that originate on a body of water. Within this category there are two types: those that originate as a result of an electrical storm and those that do not.

Waterspouts that arise from a thunderstorm are formed in the same way as a tornado and are capable of sinking boats and churning the seas, depending on their intensity. On the other hand, those that do not arise as a result of a thunderstorm pose much less danger.

Land waterspouts

Landspouts or “waterspouts” are small tornadoes that form without the need for a storm to occur previously, so they are not supercells.

Like waterspouts, terrestrial waterspouts are weak, short-lived, and have a small vortex. Its characteristics mean that most of the times they fail to cause significant damage.

Gustnado

Many scientists consider that these types of eddies do not belong to the group of tornadoes; however, others qualify it as one of the non-supercell eddies.

This type of meteorological phenomenon is characterized by being a whirlpool whose intensity is much lower than that of another whirlwind, so it does not cause significant damage.

Dust swirl

The dust eddy, also known as the dust devil, is a stream of wind that picks up sand or dust from the ground. Its origin is not associated with storms, on the contrary, they can form in good weather conditions; especially when there is intense solar radiation during days with cold winds.

Although not considered by many to be a tornado, these types of eddies can cause significant structural damage.

Fire swirl

This particular type of eddy can form in the vicinity of fires and could join a cumulonimbus cloud. The swirl of fire (or fire devil) is characterized as a column of fire that rises up to the sky, which results in a high risk due to the spread of flames.

Steam swirl

Steam eddies, also known as steam devils, are extremely rare. They are identified by being columns of smoke or vapor that can form in places such as hot springs or deserts.

Consequences

To determine the consequences of devastation after a tornado strikes, a system called the "Fujita Scale" is used, a system to measure the intensity of tornadoes based on the severity of the damage they cause in their wake.

F0

Those that are considered the weakest are classified as category F0: they register winds between 60 kilometers and 117 kilometers per hour and cause deterioration in the branches of the trees, as well as damage to television antennas and traffic signals.

F1

Characterized by having winds between 117 kilometers per hour and 181 kilometers per hour, category F1 tornadoes can damage tiles, break windows, overturn vehicles, or damage structures that are slightly more resistant than trees or signs on public roads.

F2

After category F1 tornadoes, the natural events that follow on the intensity scale are category F2. With winds that register a speed between 181 kilometers per hour and 250 kilometers per hour, this type of tornado is capable of uprooting trees by the roots and detaching roofs.

F3

Considered one of the most dangerous categories, F3 category tornadoes are capable of sustaining winds with speeds between 250 kilometers per hour and 320 kilometers per hour.

Once at this point, natural events devastate entire forests, as well as dislodge the walls and roofs of homes.

F4

With sustained winds between 320 kilometers per hour and 420 kilometers per hour, category F4 tornadoes cause significant damage such as the loss of the foundations of buildings and the overturning of vehicles they manage to reach.

F5

Considered the highest intensity tornado that could be recorded, category F5 natural events are those whose winds are capable of reaching speeds ranging from 420 kilometers per hour to 510 kilometers per hour.

Once the tornado reaches the F5 category, it is capable of destroying buildings, lifting trains and taking cars, trees or any other object with a similar weight with it.

One of the countries with the highest incidence of tornadoes in its territory is the United States: its wide terrain and the lack of mountains to stop the course of the natural event are the main causes that make this country one of the most affected. Up to 1,200 tornadoes have been registered annually in the North American territory.

F6

Category F6 events produce such catastrophic damage that it is difficult to describe their power. These types of tornadoes reach speeds between 512 and 612 kilometers per hour, but they are very rare.

In fact, only one event of this magnitude has been recorded in the history of humanity, which occurred in 1999, in Oklahoma, United States.

References

1. Tornadoes, National Geographic Portal, (nd). Taken from nationalgeographic.com
2. Cumulonimbus Clouds, Met Office, 2018. Taken from mettofice.gov.uk
3. Severe Weather 101: Types of Tornadoes, NSSL Portal The National Severe Storms Laboratory, (nd). Taken from nssl.noaa.gov
4. Identifying nature's dangerous whirlwinds: A guide to 5 types of tornadoes, Brian Lada, Portal AccuWeather, (nd). Taken from accuweather.com
5. Fujita Tornado Damage Scale, National Oceanic and Atmospheric Administration, (nd). Taken from noaa.gov