Lightning & Thunderstorms - Nature’s Equalizer
One of the most powerful of all natural phenomena is lightning. Coming in numerous forms, occurring just about anywhere on the planet, and able to strike at various speeds and powers, lightning is a force to be reckoned with. While singularly beautiful, lightning can also be frightening, loud, and destructive.
What exactly is lightning?
The exact science behind lightning remains a mystery. Basically, meteorologists and other scientists have determined that lightning is a massive electrostatic charge that occurs under a variety of conditions, usually thunderstorms, but sometimes it accompanies volcanic eruptions, heavy snows, dust storms, severe forest fires, hurricanes and even nuclear detonations.
How nature creates lightning is the unknown factor although a study of the situations where it is present shows a pattern toward turbulent air. Humidity, friction, atmospheric pressure, and wind…including solar wind…are all believed factors in the formation of lightning. Another important ingredient seems to be ice, which scientists feel forces a separation between oppositely charged ions, creating a spark.
When charges are driven apart, for whatever reason, it is called electrostatic induction. This process begins with a powerful updraft that propels water upwards where it is supercooled and eventually collides with ice crystals already present, creating a mushy, cold wet substance called graupel. The collision causes a positive charge to flow into the ice crystals and a negative charge to transfer to the graupel. As the draft continues to push the lighter ice crystals upwards, the top of the cloud begins to develop a positive charge significant enough to be released as lightning.
A similar theory, which encompasses some of the electrostatic debate, involves polarization. Here, ice crystals or droplets of moisture are polarized as they fall through the Earth’s natural electric field. When they reach the updrafts within a cloud, the same general process of electrostatic induction occur, releasing a bolt of lightning.
The runaway breakdown theory is perhaps more complex, but is also utilized in several other ideas about lightning initiation. This theory was proposed in 1992 and suggests that cosmic rays ionize atoms, which in turn release electrons. These electrons make their way through electric fields and in turn ionize other air molecules, making the air conductive to electricity and triggering a lightning strike. Leader strokes can move down the cloud in varying increments (steps) with a very visible charge to follow.
Similar to this theory, is one of mysterious gamma ray emissions triggering lightning strikes. This theory is under investigation by NASA and currently many thunderheads are monitored by space shuttles and other observation mechanisms. This is a perplexing but hot theory in the formation of electricity. The fact of the matter remains that all theories have some validity, but none can fully explain how this charge is generated in so many different situations and in so many different areas of the world. Moreover, there seem to be many different types of lightning.
Common types of lightning:
The most common lightning stroke actually occurs
within a thunderhead that produces it and most remain unseen by people because
of the thick cloud cover associated with the storm. They appear to be little
more than weak flashes of light silhouetted in the sky. The strokes people are
likely most familiar with are cloud to ground strokes that occur between a
cumulonimbus cloud and the ground. These are usually initiated by a leader
stroke, and are probably the most well known because they are both the most
visible and the most destructive.
Bead lightning is a type of cloud to ground lightning, but it has a distinctly different look than traditional strikes. As the stroke moves toward the ground, it appears to split into a series of short and bright bursts. Ribbon lightning is similar in appearance to bead lightning, but is caused by high winds that move successive strikes over from the site of each previous stroke, giving the impression of a moving and flowing ribbon. Staccato and forked lightning are short but bright blasts that feature a forking pattern.
Of course, lightning does not need to contact the ground at all. Inter and intra cloud lightning are both fairly common and occur between two clouds, or within a single cloud, respectively. This is commonly called heat lightning, since it seems to occur often on hot summer nights and can be witnessed at amazing distances while the clouds are lit up in the night sky. It is usually at such a distance that no thunder can be heard. Thunder, incidentally, always accompanies lightning. Sometimes, such as in the case of heat lightning, it is just too far away for the ear to hear, but it is always present.
While all of these are examples of naturally occurring lightning, it is also possible for lightning to be triggered by the actions of people on the planet or in the atmosphere. If conditions for an electric charge are simulated or synthetically produced, a strike of a different nature occurs. For example, lightning rockets have been launched into thunderheads to induce strikes for study. These rockets carry spools of wire that unravel and offer a path for the lightning to follow. Similarly, lightning has been known to strike aircraft when the phenomenon is desirous of a path. The Apollo 12 was even struck by lightning shortly after launch. Laser testing and nuclear detonations will do roughly the same thing and have been known to induce lightning strikes.
How powerful is it?
Lightning is truly a powerful force of nature, whether it is a step leader or distant intra cloud bolt being studied. While lightning looks to be enormous and deadly from nearly any distance, most of the size we associate with lightning is simply illumination. The longest recorded bolt was 180 miles long. The actual current channel, however, is not much larger than a standard ballpoint pen. This is a hot and powerful pen. The air within this core of lightning is heated to a temperature of 54,000 degrees Fahrenheit, about six times hotter than the surface of the sun. Accompanying these incredible temperatures is a typical discharge of about 30,000 amps, though intra cloud charges may be only a few thousand amps. Superbolts from some high voltage positive lightning, however, have been recorded at an amazing 300,000 amps or more. A standard “C-Cell” battery is 1.5 volts and homes are typically equipped with power outlets ranging from 100 to 230 volts. A lightning bolt can carry a charge of up to a billion volts.
But is it useful?
As powerful as lightning is, it continues to do more harm than good in the world. Trying to harvest the power of lightning has been deemed virtually hopeless by the scientific world. Forcing lightning to go where it is bid is the first and most obvious problem and many expensive lightning towers would have to be erected in an area that is frequented by thunderstorms. The other defying factor is that a lightning strike is so short lived that its rapid burst of power is over practically before it begins. Rudimentary experiments from the eighties to present have shown that the energy harvested from an average bolt of cloud to ground lightning could possibly power a single household light bulb for several months. Ironically, lightning strikes destroy millions of dollars worth of electrical transformers each year, creating costly repairs and raising the expense of electrical power.
Lightning has, however, been reported to have some positive effects. It is undeniably powerful and beautiful, making it the subject of thousands of photographs. However, without lightning, scientists believe that the Earth would lose its natural electric charge very quickly and a dangerous imbalance would occur. Lightning also electrifies nitrogen so that it is dissolved into water, creating a rich natural fertilizer for plants, which can only absorb this necessary nutrient through their roots. Lightning is also a leader in rebuilding and creating ozone gas, which protects the Earth and its inhabitants from harmful ultraviolet rays from the sun.
A damaging force
With all of its might, it is a scientific irony that fewer than thirty percent of all humans struck by lightning actually die. Fewer than five hundred people are injured annually by lightning strikes within the U.S., about one hundred of which die. It is the second most common weather related killer of people. It strikes the ground approximately 25 million times each year in the U.S. alone. Despite the infrequency of death, it has been enough to inspire numerous adages, comparisons, and myths.
Strikes on people
Contrary to popular belief, people who are struck by lightning do not explode or burst into flames. There is often the scent of burned flesh in the air and hair will typically be singed, but people do not burst into flames. The hottest spots will likely be any area of the body that touches metal, such as near jewelry or metal fasteners, like belt buckles. The idea that a body may explode likely comes from lightning’s effect on sweat. Perspiration on a body is superheated when the body is struck by lightning, causing instant steam and air expansion. This may cause frightening phenomena, such as a person’s boots being blown of his feet or burns to occur in the underarms.
Aside from singing and obvious shock, survivors of lightning strikes report a range of afflictions ranging from momentary memory loss and blindness to long term disorders due to nerve damage. Long term memory loss, emotional disorders, and complete personality changes have all been reported in lightning strike survivors.
When groups of people are afflicted by a single lightning strike, the adage “Treat the dead first” has arisen in reference to the appropriate triage technique. Those with the ability to yell out in pain or are up flailing about are likely experiencing non-life threatening complications. Those who appear dead, are likely NOT dead, but rather in cardiac arrest and can be saved with standard CPR.
There are many other adages concerning lighting and safety. The only one that seems to ring true is “If you can hear it, fear it.” This saying urges people to take cover as soon as they can hear thunder. Lightning has been known to strike up to ten miles away from a parent storm. One that is far more popular but much less true is “Lightning never strikes the same place twice.” Over the years, this has been proven completely false. The Empire State Building is struck dozens of times each year and one man…Roy Sullivan…was struck seven times between 1942 and 1977.
Where does it strike?
Lightning can and does strike anywhere, but there are plenty of ways to improve your chances of being struck. The first is simple geographical location. The state of Florida has the highest frequency of lightning strikes due to the high surface temperature and very low-lying moist air masses above the surface. This is true of the entire Gulf Coast area. Areas near the western U.S. mountains also have a high number of cloud to ground strikes because of the turbulent air. Still, Florida has twice as many lightning related deaths as any other state. Singapore and Terasina, Brazil are two other cities with high occurrences of lightning strikes.
Non-state specific areas that are prone to lightning strikes include the middle of an open field or ball park. Scientists feel that a lone human standing in a wide expanse of nothing serves as a type of lightning rod and channels the electricity to the ground. Heavy machinery, such as that found on modern farms, serves in a similar fashion with the machinery being both tall and metal. Isolated structures are also unsafe, but the one of the worst possible shelters is beneath a tree.
Trees are commonly blown apart by lightning strikes in a manner similar to a person losing his shoes. The sap within a tree becomes superheated very quickly and expands, blowing the bark and inner pulp out of the tree. Oak and elm trees are the two most common types of trees struck, and evergreens follow closely behind them. What people don’t understand about a tree in a lightning storm is that they actually make a safe lightning rod to draw lightning from a person if the person stays AWAY from the tree instead of directly under it.
Being male also seems to add to the chances of being struck. It is unknown if a chemical makeup accounts for this sexism in lightning, or if the likelihood of males being in lightning-prone areas (such as near heavy machinery) accounts for this. Males make up over eighty percent of both fatalities and injuries due to lightning. Postal workers, farmers, and construction workers are some of the leading occupations of lightning strike victims. Popular activities that are commonly associated with lightning include swimming, golfing, fishing, and walking in an open field. Phone use is the leading cause of death of indoor lightning fatalities with bathing a close second.
It is recommended that a person seek shelter as soon as thunder can be heard. Inside a vehicle, while very dangerous during a tornado, is an excellent insulator against lightning so long as a person does not touch any metal. The metal of a car will draw the lightning safely to the ground and the tires provide somewhat of a poor insulator.
Lightning in history
While damaging, lightning has been responsible for some interesting if not fascinating incidents in recorded history. Its amazing power was recorded by early Greeks when Zeus was attributed with the ability to throw lightning bolts from the sky to express his displeasure. Since then, science has been more involved in the study of lightning, but historical facts still detail its destructive capabilities.
Some notable lightning disasters from history:
August 1769: A deadly lightning bolt strikes the Church of the Nazaire in Brescia, Italy. The strike alone was deadly enough without it having ignited 207,000 pounds of gunpowder stored in the vaults. The ensuing blast destroyed one sixth of the town and killed 3000 people.
July 10, 1926: Lightning strikes the United States Navy’s largest ammunition depot in Lake Denmark, New York. TNT Bombs and depth charges are released throughout the depot.
August 8, 1937: Three people are killed by a bolt of lightning that struck New York’s Jacob Riis Park. On August 7, almost exactly one year later, three more people were killed when lightning struck the same place.
December 8, 1963: Pan American Flight 214 is struck by lightning over Maryland. The bolt ignited the reserve fuel tank, causing a fiery crash that killed 82 people. It was the only U.S. airliner ever lost to lightning.
March 26, 1987: Lightning costs the U.S. Airforce 162 million dollars when it struck and destroyed a rocket carrying a communications satellite just forty-two seconds after it was launched.
Summer 1988: Forty-two fires started by lightning contributed to the destruction of nearly forty percent (793,800 acres) of the Yellowstone National Park.
April 10, 1994: One person was killed and eighteen more were injured by lightning during a competitive Frisbee match in Nashville, Tennessee
October 2002: Hernan Gaviria, famed Colombian soccer star, died after being struck by lightning during a training session in Cali
October 31, 2005: 68 dairy cows sheltering beneath a tree die from a lightning strike in New South Wales. Three others recover from temporary paralysis.
Other lightning facts:
- Golfers Lee Trevino and Jerry Heard were both struck by lightning during the 1975 Western Open in Chicago.
- An average American has a 1:700,000 chance to be struck by lightning in his or her life.
- The Fourth of July has historically been one of the worst days of the year for deadly lightning strikes.
- Fulgerite is the term for weird root-like particles of sand, fused together during the heat of a lightning strike.
- Almost 50 percent of the people killed by lightning in the state of Colorado between 1980 and 1991 were climbing mountains.
- The fear of lightning is called keraunophobia.
Keraunophobia should be a fear shared by all people when the damaging capabilities of lightning are reviewed. It is one of nature’s most powerful and deadly forces, one to be respected and admired.
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