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Everything You Ever Wanted to Know About Lightning
Lightning Storm strikes 8 Times !! Exclusive Video....
Have You Ever Wondered About Lighting?
It is a captivating natural event; lightning has mystified humanity since the dawning of reason. It's power is so awe inspiring as to make us cower in it's thundering wake. But most of us know so little about lightning. How dangerous is lightning? Is all lightning the same? Where does it come from? What does it do and why does it do it? Here in the article I will try to cover as much as I can on the subject of lightning. By the end of this article you will have a very extensive knowledge of the dynamics of lightning.
Question: What is lightning anyway?
Lightning - Is a very powerful electrostatic discharge producing an emission of visible light and electromagnetic radiation. It is actually the same kind of electricity that shocks you when you when you rub your sock covered feet on the floor and touch the doorknob. Lightning can strike between a cloud and the ground, within a cloud, or it can strike other clouds. Weather scientists are still trying to understand how lightning works and it's interactions with the upper atmosphere and the electromagnetic field.
Lightning is the oldest observed natural phenomenon on earth. It has been observed during large hurricanes , thunderstorms, heavy snowstorms, large intense forest fires, volcanic eruptions, and surface nuclear detonations.
Lightning is a channel of negative charge called a stepped leader that zigzags in forked segments through the atmosphere during storms. The step leader is so quick it happens faster than the human eye can perceive it. The step leader travels down to the ground as it is attracted to a positive charge coming up from the ground called a streamer. The charge will likely connect to something tall like a tree or tower. Positive and negative charges connect and a sudden return stroke sends light up to the cloud which may have as many as 20 return strokes as we see the process repeated several times along the path, the actual size of the lightning is one to two inches.
Close "clear-air" lightning bolt!
How is Lightning Created?
Lightning creation is a process where the dynamics are not well understood at this time. It is believed that precipitation and convection are involved in the electrical structure of clouds. It is thought that different sized raindrops, hail, and grauple get positive and negative charges as they collide, heavier particles carry a negative charge to the bottom of a cloud . Convection is believed to come from updrafts that blow positive charges upwards to the cloud while downdrafts carry a negative charge downward.
Storms are extremely turbulent with updrafts and downdrafts that happen close together. Those upwards flowing drafts have water drops in them from the lower clouds in the storm. These winds carry those drops up to altitudes of 35,000 to 70,000 feet high, that's miles over the freezing altitude. Downdrafts carry hail and ice from the higher altitudes towards the ground at the same time the updrafts are carrying other drops upwards and freezing them. On the way up and down these frozen drops of hail, rain help to create soft hail or graupel. As the graupel collides with the water drops and ice particles something amazing occurs where negatively charged electrons are torn off the rising particles and collect on the falling particles. This gives the storm cloud a negative charge at its base and a positive charged at the top.
Since the two charges are attracted to one another the positive and negative areas become more distinct and an electrical field is formed within the cloud. The further these areas are from one another the stronger the electrical field and the strong the attraction between the charged zones. The atmosphere is a great insulator though, this inhibits the electrical field. So a large charge is built up within the atmosphere before the strength of the electrical field can overpower the air's insulating properties. At that moment though the current forces a path through the air until it makes a strong connection. It is then that we see a stroke of lightning. On the ground a positive charge pools within the earth. The charge shadows the storm wherever it goes, it is responsible fo the cloud to ground lightning. The electrical field in the storm is much stronger than the one between the storms base and the earth's surface so most of the lightning we see is inside the storm cloud itself.
NWS NOAA Weather Fatality Data Chart
Lightning is Dangerous!
Cloud to Ground
How many people are killed a year by lightning?
- Lightning associated deaths according to the National Weather Service, during the past 30 years (1979-2008) Lightning killed an average of 58 people a year. There are about 300 medically documented injuries per year, although undocumented numbers are said to be higher.
Does lightning strike from the ground up or from the sky down?
- It does both, there is cloud to ground lightning which comes from the sky down but the flash you see is from the ground up. What happens in this process is that the negative charge hits the ground in a series of strokes. Positive charges come from the ground. Here we see the rule of how opposites attract when an a streamer is stretched skyward from an object and is about to be struck, when the two meet the return stroke reaches back up into the sky. The return stroke makes the visible flash you see.
Where does lightning get its color? Why is it not always white or blue?
- Lightning may look different colors; it depends on the medium the light travels through to get to your eyes. In snow lightning is seen as pink or green. haze, dust, moisture, raindrops and any other particles in the atmosphere change the color through a process of absorbing and diffracting the white light of lightning.
How hot is lightning?
- The power of lightning super-heats the gases in the air to around 18,000 degrees Fahrenheit and the air can even reach temperatures as high as 60,000 degrees Fahrenheit.
Cloud Flashes, What are They?
- Cloud Flashes occur when lightning travels inside the cloud from one part of the cloud to another and in some cases from the cloud to the air.
- Sometimes cloud flashes have a visible channel extending into the air around the storm (a cloud to air discharge), it does not strike the ground. The term sheet lightning or intra-cloud lightning I,C, is referred to lightning that is only within a cloud and lights up as a sheet of light during the flash. Heat lightning is lightning illumination that is so far away that thunder can't be heard. Lightning can travel from cloud-to-cloud (CC) and it can also become Spider lightning or stepped arches of light traveling in flashes often seen on the underside of clouds.
Does lightning Serve a Purpose?
- Lightning maintains the Earth's natural electrical balance through recharging it in it's thunderstorms. The surface and the atmosphere conduct electricity easily acting like a complete circuit because the ground has a negative charge and the atmosphere has a positive charge. Currents of electrons flow upwards from surface of the Earth. Thunderstorms carry and transport the negative charges back to Earth. If not for our worlds thunderstorms the atmospheres electrical balance would vanish in less than five minutes. Lightning is also a natural producer of our very fragile ozone layer, the gas that protects us from the rays of our sun.
When lightning strikes what happens to the ground?
- The dirt and clay in the ground are fused into silica. What you get is a glassy black rock (a fulgarite) in the shape of a tube. There is often damage along the path of lightning as when lighting strikes a tree and travels down the trunk and then turns water to steam. If it heats the surface moisture of the wood it can blast shards of bark from the tree
Does lightning strike twice?
- Yes it does or at least it can hit near the same spot . The likely reason being that something about the site makes the place more likely to be struck.If the lightning strikes something on the ground, the object sent up a streamer to join the downward developing flash and created the connection to the ground.
Can you have lightning without thunder?
- No. Thunder is the result of lightning, but it may be possible that you could be to far away and not hear the thunder.Thunder iscaused by quickly expanding gases in the channel of the lightning strike. The lightning heats the gases in air to 18,000 degrees and causes the rapid expanding of the air. This makes the powerful sound wave we call thunder. The initial ripping sound is created by the stepped leader and the crack sound heard close to the strike, you hear these right before you hear the actual thunder which is created by the ground streamer.
- You can barely hear lightning at 15 miles from the lightning strike, but it has been heard up to 25 miles away. Thunder at that distance is more of a low rumbling because of the higher frequency pitches that are more easily absorbed by the environment, and the sound waves have different arrival times.
Upper Atmospheric Lightning Sprites and Elves
Blue jets and Red sprites
Other Lightning Related Phenomenon
Above the thunderstorms we all know there is other lightning phenomenon happening that we on the ground are not always aware of. In the upper atmosphere lighting discharges in short lived electrical breakdowns well above the altitudes of normal lightning storms. This lightning is believed to be electrically formed fluorescence or as meteorologist call them transient luminous events or T.L.E.s for short. There are various types of these T.L.E. discharge phenomena called blue jets, red sprites, sprite halos, gigantic jets, and ELVES.
The most common T.L.E. are sprites. Sprites are flashes of bright red light that happen above storms. There are columniform sprites which are vertical columns of red light. These sprites are called red sprites. A red sprite with tendrils are often referred to as carrot sprites. Other types of T.L.E. events are called gnomes, blue jets, gigantic jets, blue starters, and E.L.V.E.S. or (Emission of Light and Very Low Frequency perturbations from E.M.P. or Electromagnetic Pulse Sources). All of these T.L.E.s are phenomena associated with thunderstorms.
Blue Jets, Red Sprites, E.L.V.E.S., and Gigantic Jets:
- Sprites are varied in range and shape. They are triggered by the discharge of positive lightning between a thundercloud and the ground. They are normally reddish orange to greenish blue and have hanging tendrils below with arcing branches above. They often also are preceded by a red halo. They happen in clusters between 30 miles and 60 miles above the Earth's surface.
- Blue Jets are different from sprites because they are projected from the tops of thunderstorms. They are usually a narrow cone and reach up to the lowest levels of the ionosphere some 30 miles above the earth. Unlike sprites that are associated with lightning strikes blue jets are not directly triggered by lightning (it does seem that there is a correlation between blue jets and strong hail activity in thunderstorms). They are brighter than sprites and have a blue color because of the near ultraviolet emissions they expel and because of ionized molecular nitrogen. They happen much less frequently than sprites.
- Blue Starters - are an upward moving luminous phenomena related to blue jets. They are shorter and brighter than blue jets and reach up to 20 km. Blue starters are blue jets that never really make it to being blue jets.
- Gigantic Jets are extremely large jets of chaRged particles moving upwards to about 45 miles altitude at exponential speeds starting at the speed of lightning some 50,000 miles a second (the typical speed of lightning) increasing to over 160,000 miles a second that then break up and reach speeds upwards of over two million miles a second to become a burst of bright light in the ionosphere.
- E.L.V.E.S. appear as dim, flat, expanding glows 250 miles in diameter and they usually only last 1 millisecond. They happen in the ionosphere at an altitude of 62 miles over a thunderstorm. They produce a red hue. Light is generated by the excitation of nitrogen molecules because of electron collisions. It is believed these E.L.V.E.S. may also produce jets of antimatter.
Photograph or Ball Lightning
Other Lightning Phenomena
St. Elmo's Fire "is an electrical weather phenomenon in which luminous plasma is created by a coronal discharge originating from a grounded object in an atmospheric electric field (such as those generated by thunderstorms or thunderstorms created by a volcanic explosion).”
Ball lightning Ball lightning has been described as transparent, translucent, multicolored, evenly lit, radiating flames, filaments or sparks, with shapes that vary between spheres, ovals, tear-drops, rods, or disks; "is an unexplained atmospheric electrical phenomenon. The term refers to reports of luminous, usually spherical objects which vary from pea-sized to several metres in diameter. It is usually associated with thunderstorms, but lasts considerably longer than the split-second flash of a lightning bolt. Many of the early reports say that the ball eventually explodes, sometimes with fatal consequences, leaving behind the odour of sulfur." Ball Lightning have been reported to disperse in many different ways, such as suddenly vanishing, gradually dissipating, absorption into an object, "popping," exploding loudly, or even exploding with force, which is sometimes reported as damaging. Accounts also vary on their alleged danger to humans, from lethal to harmless.
Ball Lightning Characteristics:
- They frequently appear almost simultaneously with cloud-to-ground lightning discharge
- They are generally spherical or pear-shaped with fuzzy edges
- Their diameters range from 1–100 cm, most commonly 10–20 cm
- Their brightness corresponds to roughly that of a domestic lamp, so they can be seen clearly in daylight
- A wide range of colours has been observed, red, orange and yellow being the most common.
- The lifetime of each event is from 1 second to over a minute with the brightness remaining fairly constant during that time
- They tend to move, most often in a horizontal direction at a few metres per second, but may also move vertically, remain stationary or wander erratically.
- Many are described as having rotational motion
- It is rare that observers report the sensation of heat, although in some cases the disappearance of the ball is accompanied by the liberation of heat
- Some display an affinity for metal objects and may move along conductors such as wires or metal fences
- Some appear within buildings passing through closed doors and windows
- Some have appeared within metal aircraft and have entered and left without causing damage
- The disappearance of a ball is generally rapid and may be either silent or explosive
- Odors resembling ozone, burning sulfur, or nitrogen oxides are often reported
A Dirty Thunderstorm (AKA, Volvanic Lightning) is a weather phenomena that is produced in the plume of a volcanic eruption.
"A study in the journal Science indicated that electrical charges are generated when rock fragments, ash, and ice particles in a volcanic plume collide and produce static charges, just as ice particles collide in regular thunderstorms.
As the plume started going downwind, it seemed to have a life of its own and produced some 300 more or less normal [lightning bolts] ... The implication is that it has produced more charge than it started with. Otherwise [the plume] couldn't continue to make lightning.
—Martin Uman, co-director of the University of Florida Lightning Research program"
Personal Thoughts on Lightning
I've always been intrigued by lightning, ever since I was a boy I always looked at lightning as mother natures fireworks. It's powerful bright flash, the booming thunder that shakes ground beneath my feet, I always wondered why it behaves the way it does, and why it happens at all. Well now I know and so do you. Lightning is a pretty freaking cool thing to behold and after learning more about it I see that lightning is far more dynamic and mysterious that I would have ever imagined.