Linear lightning is characterized by a shape in the form. Types of lightning: linear, intracloud, ground
"physical phenomenon"
A giant electrical spark discharge in the atmosphere, usually manifested by a bright flash of light and accompanying thunder. The electrical nature of lightning was revealed in the studies of the American physicist B. Franklin, on the basis of which an experiment was carried out to extract electricity from a thundercloud.
Most often, lightning occurs in cumulonimbus clouds, then they are called thunderclouds; sometimes lightning is formed in nimbostratus clouds, as well as during volcanic eruptions, tornadoes and dust storms.
The process of ground lightning development consists of several stages. At the first stage, in the zone where the electric field reaches a critical value, impact ionization begins, initially created by free electrons, always present in a small amount in the air, which, under the action of an electric field, acquire significant speeds towards the ground and, colliding with air atoms, ionize them. That. electron avalanches appear, turning into filaments of electric discharges - streamers, which are well-conducting channels, which, merging, give rise to a bright thermally ionized channel with high conductivity - a step leader.
The movement of the leader to the earth's surface occurs in steps of several tens of meters at a speed of ~ 5 * 10,000,000 m/sec, after which its movement stops for several tens of microseconds, and the glow is greatly weakened; then, in the next stage, the leader again advances several tens of meters. A bright glow covers all the steps passed; then a stop and a weakening of the glow follow again. These processes are repeated when the leader moves to the earth's surface at an average speed of 2*100,000 m/s. As the leader moves towards the ground, the field strength at its end increases and under its action a response streamer is thrown out of the objects protruding on the Earth's surface, connecting with the leader.
lightning shapes
Line lightning
A discharge of linear lightning occurs between clouds, inside a cloud, or between a cloud and the ground, and usually has a length of about 2-3 km, but there are lightnings up to 20-30 km long.
It looks like a broken line, often with numerous branches. Lightning color - white, yellow, blue or reddish
Most often, the diameter of the thread of such lightning reaches a couple of tens of centimeters. This type is the most common; we see it most often. Linear lightning appears when the electric field of the atmosphere is up to 50 kV / m, the potential difference in its path can reach hundreds of millions of volts. The lightning current of this kind is about 10 thousand amperes. A thundercloud that produces a linear lightning discharge every 20 seconds has an electrical energy of 20 million kW. The potential electrical energy stored in such a cloud is equal to the energy of a megaton bomb.
This is the most common form of lightning.
Flat zipper
Flat lightning looks like a scattered flash of light on the surface of clouds. Thunderstorms, accompanied only by flat lightning, are classified as weak, and they are usually observed only in early spring or late autumn.
Tape zipper
Ribbon lightning - several identical zigzag discharges from clouds to the ground, parallel shifted relative to each other with small or no gaps.
Bead lightning
A rare form of electrical discharge during a thunderstorm, in the form of a chain of luminous dots.The lifetime of bead lightning is 1–2 seconds. It is noteworthy that the trajectory of bead lightning often has a wave-like character. Unlike linear lightning, the trail of bead lightning does not branch - this is a distinctive feature of this species.
rocket lightning
Rocket lightning is a slowly developing discharge, lasting 1–1.5 seconds. Rocket lightning is very rare.
Ball lightning
Ball lightning is a bright luminous electric charge of various colors and sizes. Near the ground, it most often looks like a ball with a diameter of about 10 cm, less often it has the shape of an ellipsoid, a drop, a disk, a ring, and even a chain of connected balls. The duration of the existence of ball lightning is from several seconds to several minutes, the color of the glow is white, yellow, light blue, red or orange. Usually this type of lightning moves slowly, almost silently, accompanied by only a slight crackling, whistling, buzzing or hissing. Ball lightning can penetrate into enclosed spaces through cracks, pipes, windows.
A rare form of lightning, according to statistics, there are 2-3 ball lightning per thousand ordinary lightning.
The nature of ball lightning is not fully understood. There are many hypotheses about the origin of ball lightning, from scientific to fantastic.
curtain zipper
Curtain lightning looks like a wide vertical band of light, accompanied by a low low rumble.
Volumetric lightning
Bulk lightning is a white or reddish flash with low translucent clouds, with a strong crackling sound “from everywhere”. It is more often observed before the main phase of a thunderstorm.
strip zipper
Strip lightning - strongly resembles the aurora, "laid on its side" - horizontal stripes of light (3-4 stripes) are grouped on top of each other.
Elves, jets and sprites
Elves (English Elves; Emissions of Light and Very Low Frequency Perturbations from Electromagnetic Pulse Sources) are huge, but dimly luminous flash cones with a diameter of about 400 km, which appear directly from the top of a thundercloud.
The jets are blue tube-cones.
Sprites - a kind of lightning, beating up from the cloud. For the first time this phenomenon was recorded in 1989 by accident. Very little is known about the physical nature of sprites.
Jets and Elves form from the tops of the clouds to the lower edge of the ionosphere (90 kilometers above the Earth's surface). The duration of these aurora is a fraction of a second. To photograph such short-lived phenomena, high-speed imaging equipment is needed. Only in 1994, flying in an airplane over a big thunderstorm, did scientists manage to capture this amazing sight.
Other phenomena
flashes
Flashes are white or blue silent flashes of light observed at night in partly cloudy or clear weather. Flashes usually occur in the second half of summer.
Zarnitsa
Zarnitsy - reflections of distant high thunderstorms, visible at night at a distance of up to 150 - 200 km. The sound of thunder during lightning is not heard, the sky is cloudy.
Volcanic Lightning
There are two types of volcanic lightning. One arises at the crater of the volcano, and the other, as seen in this image of the Puyehue volcano in Chile, electrifies the smoke of the volcano. Water and frozen ash particles in the smoke rub against each other, and this causes static discharges and volcanic lightning.
Lightning Catatumbo
Catatumbo lightning is an amazing phenomenon that is observed in only one place on our planet - at the confluence of the Catatumbo River into Lake Maracaibo (South America). The most amazing thing about this type of lightning is that its discharges last about 10 hours and appear at night 140-160 times a year. Catatumbo lightning is clearly visible at a fairly long distance - 400 kilometers. Lightnings of this kind were often used as a compass, from which people even nicknamed the place of their observation - “Maracaibo Lighthouse”.
Most say that Catatumbo lightning is the largest single ozone generator on Earth, because. winds coming from the Andes cause thunderstorms. Methane, which is abundant in the atmosphere of these wetlands, rises to the clouds, fueling lightning discharges.
Scientists know that linear lightning - the kind you often see during thunderstorms - is a spark discharge of huge electric charges that accumulate under special conditions in the lower atmosphere. The shape of lightning usually resembles the roots of a giant tree that has suddenly grown in the sky. The length of linear lightning is usually several kilometers, but can reach 20 km or more. The main "spark" of lightning has several branches 2-3 km long. The diameter of the lightning channel is from 10 to 45 cm, and it "lives" only tenths of a second. Its average speed is about 150 km/s.
Most often, lightning occurs in powerful cumulonimbus clouds - they are also called thunderstorms. Less commonly, lightning occurs in nimbostratus clouds, as well as during volcanic eruptions, tornadoes, and dust storms.
Lightning discharges can occur between neighboring electrified clouds, between a charged cloud and the ground, or between different parts of the same cloud. In order for a discharge to occur, a very significant difference in electrical potential must occur. This can happen during rain, snowfall, hail and other complex natural processes. The potential difference can be tens of millions of volts, and the current inside the lightning channel reaches 20,000 amperes.
Scientists still have not come to a consensus on how and why such huge charges arise in thunderclouds. There are several theories on this subject, and each of them describes at least one of the reasons for this phenomenon. So, in 1929, a theory appeared that explains the electrification in a thundercloud by the fact that raindrops are crushed by air currents. Larger drops are positively charged and fall down, while smaller ones remaining in the upper part of the cloud acquire a negative charge. Another theory - it is called induction - suggests that the electric charges in the cloud are separated by the electric field of the Earth, which itself is negatively charged. There is another theory - its authors believe that electrification occurs as a result of the fact that drops of different sizes in the atmosphere absorb gas ions with different charges.
About 100 linear lightning discharges occur on Earth every second, and during the year it strikes every square kilometer of its surface six times. Sometimes lightning can behave in a completely inexplicable way.
There are cases when lightning:
She burned linen on a man, leaving his outer clothing intact;
She snatched metal objects from the hands of a person and did not harm him;
Melted together all the coins in the wallet without damaging the paper money;
She completely destroyed the medallion on the chain worn around the neck, leaving on the skin of a person the imprint of the chain and the medallion, which did not come off for several years;
Three times she hit a man without harming him, and when he died after a long illness, for the fourth time she landed on a monument on his grave.
Even stranger stories are told about people struck by lightning, but not all of them have confirmation. The only thing that the statistics show is that lightning strikes men six times more often than women.
Even though the force of the discharge is incredibly high, most people who get struck by lightning do not die. This happens because the main lightning current seems to “flow” over the surface of the human body. Most often, the case is limited to severe burns and lesions of the cardiovascular and nervous systems, and the victim of this natural phenomenon needs urgent medical attention.
The most frequent "target" of lightning are tall trees, primarily oaks and beeches. Interestingly, among violin and guitar makers, the wood of trees struck by lightning is considered endowed with unique acoustic properties.
The most interesting of them are presented in this article.
Linear lightning (cloud-ground)
How to get such lightning? Yes, it's very simple - all that is required is a couple of hundred cubic kilometers of air, a height sufficient for the formation of lightning and a powerful heat engine - well, for example, the Earth. Ready? Now take the air and sequentially begin to heat it. When it starts to rise, with each meter of rise, the heated air cools, gradually becoming colder and colder. Water condenses into ever larger droplets, forming thunderclouds.
Remember those dark clouds above the horizon, at the sight of which the birds fall silent and the trees stop rustling? So, these are the thunderclouds that give rise to lightning and thunder.
Scientists believe that lightning is formed as a result of the distribution of electrons in the cloud, usually positively charged from the top of the cloud, and negatively from. The result is a very powerful capacitor that can be discharged from time to time as a result of the abrupt transformation of ordinary air into plasma (this is due to the increasingly strong ionization of atmospheric layers close to thunderclouds).
Plasma forms peculiar channels, which, when connected to the ground, serve as an excellent conductor for electricity. Clouds are constantly discharged through these channels, and we see the external manifestations of these atmospheric phenomena in the form of lightning.
By the way, the air temperature in the place where the charge (lightning) passes reaches 30 thousand degrees, and the speed of lightning propagation is 200 thousand kilometers per hour. In general, a few lightning bolts were enough to power a small town for several months.
Lightning earth-cloud
And there are such lightning. They are formed as a result of the accumulating electrostatic charge on top of the tallest object on earth, which makes it very "attractive" for lightning.
Such lightning is formed as a result of “breaking through” the air gap between the top of a charged object and the bottom of a thundercloud. The higher the object, the more likely it is that lightning will strike it. So they say the truth - you should not hide from the rain under tall trees.
lightning cloud-cloud
Yes, individual clouds can “exchange” with lightning, striking each other with electric charges. It's simple - since the upper part of the cloud is positively charged, and the lower part is negatively charged, nearby thunderclouds can shoot each other with electric charges.
It is quite common for lightning to break through one cloud, and much rarer for lightning to travel from one cloud to another.
Horizontal zipper
This lightning does not hit the ground, it spreads horizontally across the sky. Sometimes such lightning can spread across a clear sky, coming from a single thundercloud. Such lightning is very powerful and very dangerous.
Tape zipper
This lightning looks like several lightning bolts running parallel to each other. There is no mystery in their formation - if a strong wind blows, it can expand the plasma channels, which we wrote about above, and as a result, such a differentiated lightning is formed.
Beaded (dotted zipper)
This is a very, very rare lightning, it exists, yes, but how it is formed is still anyone's guess. Scientists suggest that dotted lightning is formed as a result of the rapid cooling of some sections of the lightning track, which turns ordinary lightning into dotted lightning. As you can see, this explanation clearly needs to be improved and supplemented.
sprite lightning
So far, we have only talked about what happens below the clouds, or at their level. But it turns out that some types of lightning are higher than clouds. They have been known since the advent of jet aircraft, but these lightning bolts were photographed and filmed only in 1994.
Most of all, they look like jellyfish, right? The height of the formation of such lightning is about 100 kilometers. So far, it is not very clear what they are. Here are photos and even videos of unique sprite lightning. Very nice.
Ball lightning
Some people claim that ball lightning does not exist. Others post videos of fireballs on YouTube and prove it's all real. In general, scientists are not yet firmly convinced of the existence of ball lightning, and the most famous proof of their reality is a photo taken by a Japanese student.
Saint Elmo's fires
This, in principle, is not lightning, but simply the phenomenon of a glow discharge at the end of various sharp objects. The fires of St. Elmo were known in antiquity, now they are described in detail and captured on film.
Volcanic lightning
These are very beautiful lightning bolts that appear during a volcanic eruption. It is likely that the charged gas-dust dome, penetrating several layers of the atmosphere at once, causes disturbances, since it itself carries a rather significant charge. It all looks very beautiful, but creepy. Scientists do not yet know exactly why such lightning is formed, and there are several theories at once, one of which is outlined above.
Here are some interesting facts about lightning that are not often published:
* Typical lightning lasts about a quarter of a second and consists of 3-4 discharges.
* An average thunderstorm travels at a speed of 40 km per hour.
* There are 1,800 thunderstorms in the world right now.
* The US Empire State Building is struck by lightning an average of 23 times a year.
* Lightning strikes aircraft on average once every 5-10 thousand flight hours.
* The probability of being killed by lightning is 1 in 2,000,000. Each of us has the same chance of dying from falling out of bed.
* The probability of seeing ball lightning at least once in a lifetime is 1 in 10,000.
* People who were struck by lightning were considered to be marked by God. And if they died, they supposedly went straight to heaven. In ancient times, victims of lightning were buried at the place of death.
What should you do when lightning approaches?
In the House
* Close all windows and doors.
* Unplug all electrical appliances. Do not touch them, including phones, during thunderstorms.
* Keep away from bathtubs, faucets and sinks as metal pipes can conduct electricity.
* If ball lightning has flown into the room, try to get out quickly and close the door on the other side. If you can't, at least freeze in place.
On the street
* Try to go into the house or car. Do not touch metal parts in the car. The car should not be parked under a tree: suddenly lightning will strike it and the tree will fall right on you.
* If there is no shelter, go to an open area and, bending over, snuggle up to the ground. But you can't just lie down!
* In the forest, it is better to hide under low bushes. NEVER stand under a free-standing tree.
* Avoid towers, fences, tall trees, telephone and electrical wires, bus stops.
* Stay away from bicycles, barbecues, other metal objects.
* Keep away from the lake, river or other bodies of water.
* Remove all metal from yourself.
* Do not stand in the crowd.
* If you are in an open area and you suddenly feel your hair stand on end, or hear a strange noise coming from objects (that means lightning is about to strike!), bend forward with your hands on your knees (but not on the ground). The legs should be together, the heels pressed against each other (if the legs do not touch, the discharge will pass through the body).
* If a thunderstorm caught you in a boat and you no longer have time to swim to the shore, bend down to the bottom of the boat, join your legs and cover your head and ears.
In addition to the two most famous types of lightning - linear and ball - there are many little-known and little-studied - beaded, sprite, current and blue jets, sitting discharges, St. Elmo's fires. Each of these types of lightning has its own peculiarities. characteristics and poses a danger to people and buildings.
Ball lightning
Ball lightning resembles a luminous ball with an average diameter of 12 to 25 centimeters, capable of moving through the air in an arbitrary direction. The average lifetime of ball lightning is estimated at 3-5 seconds, however, there is evidence that the lifetime of ball lightning can be up to 30 seconds. An unusual phenomenon is associated with ball lightning - metal objects of small mass, in the immediate vicinity of the discharge, become weightless. For example, eyewitnesses have repeatedly noted that when they met with ball lightning, rings slipped from their hands.
Ball lightning is not yet sufficiently studied by science. At present, intensive experiments are being carried out in specialized laboratories to obtain artificial ball lightning.
current jets
Current jets do not necessarily appear during a thunderstorm - they can also appear in clear weather, with strong winds, in the form of blue flashes that are difficult to see.
Saint Elmo's fire
The fires of St. Elmo amaze with their beauty. Most often they can be observed in the form of a specific glow around the spiers of towers and ship masts. In the old days, this phenomenon was interpreted as a divine sign. According to legend, the parishioners of the Church of St. Elmo once saw an unusual glow around the cross on one of the towers. So this type of discharge got its modern name. However, it has been observed before. Already in the ancient Greek texts we find evidence of the "fires of Castor and Pollux", which were considered a good omen.
The physical meaning of the phenomenon is rather prosaic. The glow occurs in a dry and highly electrified atmosphere, when the intensity of the electromagnetic field reaches the level of several tens or hundreds of thousands of volts per meter. The glow occurs when there are dielectric particles in the air - snow, sand, dust. They rub against each other, thereby forming an increase in the electric field strength. As a result, a characteristic glow appears in the air.
Sprites
In the mid-1990s, a new type of lightning discharge was discovered. It was recorded at an altitude of 60 km above sea level in the form of short optical flashes. They were called sprites. The color and shape of sprites can vary greatly. Scientists still know little about this phenomenon. It is only known that their occurrence is associated with discharges running between the ionosphere and thunderclouds. The difficulty in studying sprites is that they appear at an altitude at which it is difficult to fix them both with the help of probes and rockets, and with the help of satellites.
It is believed that sprites occur only over strong thunderstorms and are provoked by super-strong discharges between the earth and clouds.
elves
Elves are huge cone-shaped flashes with a faint glow. Their diameter can reach 400 kilometers. Elves appear directly above the thundercloud and can reach a height of up to 100 kilometers. The duration of the discharge is up to 5 milliseconds.
Jets
these are discharges, shaped like tubes and cones up to 70 kilometers high, the duration of the existence of jets is approximately the same as that of elves.
Element - it simply enchants in its incomprehensibility. And from time immemorial, lightning has inspired poets to create famous masterpieces. Remember at least these lines of Tyutchev:
"I love the storm in early May,
When spring, the first thunder,
As if frolicking and playing,
Rumbles in the blue sky."
However, physicists have their own romance - numbers, formulas, calculations. They also decomposed the phenomenon of lightning into facts. And it is precisely because of this that we can single out the following types of lightning today.
Linear lightning (cloud-ground)
The discharge of such lightning occurs between the clouds. Moreover, it can occur, both between the cloud and the ground, and inside the clouds. Its length usually does not exceed 3 meters, however, phenomena of 20 meters in length have also been observed.
This type is the most common and has the shape of a broken line, from which there are several branches. Its color is often white, but there are also yellow and even blue variants.
Lightning earth-cloud
The reason for the formation of such lightning is the accumulation of an electrostatic discharge on top of the highest object on earth. Thus, it becomes an "appetizing" bait for lightning that breaks through the air gap between the cloud and the charged object.
In other words, the higher the item, the more likely it will become lightning prey, so never hide from bad weather under tall trees.
lightning cloud-cloud
Such phenomena occur as a result of the "exchange" of lightning (essentially electrical charges) between clouds. This is easy enough to explain, since the top of the cloud is positively charged, while the bottom is negatively charged. As a result, nearby clouds can sometimes "shoot" these charges at each other.
But here it is worth saying that quite often you can see lightning that breaks through a cloud, but when it comes from one cloud to another, you can notice it less often.
Horizontal zippers
As you may have guessed, such lightning does not hit the ground, but spreads over the entire surface of the sky. Perhaps this is one of the most spectacular phenomena. But at the same time, it is precisely such a discharge that is the strongest and poses a great threat to the living.
Tape zipper
Such a natural phenomenon consists in the occurrence of several lightning bolts, which run exactly parallel to each other. The reason for their appearance lies in the action of the wind force, which can expand the plasma channels in each lightning, as a result of which such differentiated options appear.
Beaded lightning
This is the rarest variant of lightning. And the reasons for its occurrence are not known to scientists. And the thing is that it is represented by a dotted line, not a solid line. There is an assumption that some of its sections cool down on the way to the ground. And it is as a result of this that ordinary lightning becomes beaded. But you yourself can agree that the explanation looks at least strange.
Ball lightning
It is this phenomenon that is legendary, in particular that they can incinerate or destroy jewelry. Of course, they are dangerous to humans, but most of the stories are just fictional horror stories.
sprite lightning
Remarkably, these lightnings are formed above the clouds, at an altitude of about 100 km. Alas, little is known about them. And although they became known with the advent and development of aviation, photographs of this fascinating phenomenon have become available only now.
Volcanic
These are the last types of lightning that we will consider. They occur during volcanic eruptions. Scientists tend to explain this phenomenon by the fact that the resulting dust dome breaks through several layers of the atmosphere at once, and since it carries with it a colossal charge, it naturally causes disturbances.
All the phenomena described are very spectacular and capable of bewitching. But at the same time, their beauty is deadly for a person. Therefore, we can only admire the incomprehensible power that nature shows us and try to disarm ourselves from the raging elements.
