Occurrence And History Of Lightning
Even before, human beings existed on earth, lightning stroked the earth. It is even believed that the planet’s evolution is due to the effects of lightning. All over the world, the sky is usually lighted at around one hundred in terms of seconds. Furthermore, when lightning occurs, the bolts do not all reach the ground. For example, in the United States, it is estimated that lightening occurs twenty five million times. Most people associate lightning with negative aspects, but it should be known that it has its positive aspects. Lightning is known to cause extreme damage particularly for objects and people that are not well protected. It should be known that when compared to other natural disasters, lightning does not kill many people. On a yearly basis, lightning strikes at least one aircraft, which is in the sky. Luckily, modern aircrafts have been constructed in a way that they are not affected by lightning strikes. Moreover, many forest fires, as well as failure of electric power lines are caused by lightning. The advantage of lightning in forest fires is one that cannot be ignored. It helps in ensuring that the forests constantly have a life cycle that is natural (Dwyer, 2005).
Lightning is described as being an electric discharge that has an extremely high current. It then releases pulses that are in the form of energy at one hundredth millionth seconds. It is usually measured in terms of miles, and it has a diameter that measures two or one inches. Most lightning bolts have tens of thousands of peak currents in the form of amperes. They have temperatures, which are as high as 50000 Fahrenheit degrees. The heat is hotter than even the sun, as its heat is five times more deadly. Lightning columns have plasma’s, which are extremely high in temperature (Rakov & Uman, 2003). The plasma has broken atoms that exist in the form of gas and are usually particles, which are charged electrically. They also have positively charged ions and negatively charged ions. The gases are known to be ionized in nature. The charged particles movement is the one responsible for creating a lightning channel. The latter is what makes up the electrical current whereby, the electrons move.
When ice crystals and soft hail are electrically charged when in the air, lightning arises. Thereafter, negative and positive charges accumulate and in various, diverse regions. In turn, large voltage develops at the regions, which have been charged. The regions are at the ground and the charged region. The voltage then expands in size until it has a million volts ranging from fifty to five hundred. There is also a chance that ionization of the air may take place. Furthermore, a plasma column is formed, and it has a channel that is electrically conducted. This is the time people are able to see lightning in the sky. It should be known that there are various ways as well as directions through, which lightening develops. At most, in the cloud to cloud lightening that occurs globally, there is a 90% chance of it hitting the ground. The latter is due to negative charges, which are transported to the ground, from the clouds. This is referred to as negative downward lightening. The other types of lightening, which exist, are positive upward, negative upward and positive downward discharges. In some rare instances, lightning usually moves upwards even in buildings, such as the New York Empire State Building (Dwyer, 2005).
Lightning occurs at an extremely fast speed that people cannot view it well. It even becomes impossible for people to appreciate its complex structure as well as its development stages. Fortunately, it is possible to determine the lightning development direction. Most times, one can view lightning’s main channel as well as its branches. There are many individual strokes in any given lightening flash. Also, they follow a similar cloud to ground path when lightning occurs. In any given channel, the constant recreation of the plasma takes place on a regular basis. In between the strokes, there are dark intervals and they last up to many milliseconds. The latter is the reason why people often see flickering light during a lightening episode. During a flash of lightning, there are usually five or three stokes. Moreover, people can observe strokes ranging from about one even up to twenty six (Rakov & Uman, 2003).
In every stroke that is downward, there are leaders, which always move downwards. Later on, there is a return stroke that moves in an upward direction. A conducting path is created by the leader, which intersects between the ground and the cloud. Furthermore, negative charges are distributed on the route that has been created. Also, in the path, the return stroke moves to the cloud from the ground. In turn, positive charges are distributed in order to neutralize, and at the same time, make the leader become negative. In any lightning flash, there are electrical currents, and they have diverse strokes. There is usually a rapid, current rise by the return stroke, and it can even reach up to many thousand amperes. During the current’s initial phase, many amperes move and in a second, can transmit even thousandths of amperes. The channel is in turn heated up due to the return stroke that is high. In some cases, it reaches up to 50000 degrees Fahrenheit. Also, the pressure is higher than that of the usual atmospheric pressure. Later on, intense light is produced by the channel. This is what human beings view and it can even expand. Shock waves are usually produced, and people hear thunder, which is a sound wave (Rakov & Uman, 2003).
It is extremely impossible, as well as impractical, to extract energy that is useful from lightning. In every cloud to ground lightning, there is a lot of energy consumption. The flashes usually last and has energy that is 360 kilowatts in every hour. The same energy can be used in lighting light bulbs that have a 100 Watt capacity, and for one month duration. Also, energy produced by the lightning flash varies from one hundredth to one thousandth. It is then taken to a strike point, and most energy is usually lost at this stage. Moreover, other energy then exists in the form of radio waves, light and thunder, after air has been heated up. If people had the ability of containing the energy produced by lightning flashes, they would have many difficulties. The latter is because there are extremely low chances that lightning can strike the ground. An example is a lightning incident that took place in Florida. There was a tower that was sixty meters in length and lightning struck it. Ever since, lightning strikes it on a yearly basis. Florida does not have many incidents of lightning as compared to other American states. Thus, in order to capture strikes created by lightning, many towers would have to be built (Gosline, 2005).
It is possible to test and to research about lightning concerning how it can be triggered. When this is done, it can be extremely beneficial in protecting buildings and people. The most common and safest way of inducing lightning is by using a rocket. It is then charged over head where the cloud is located. The rocket usually has a grounded wire, which is thin, and it trails behind it. There are other regions other than in the atmosphere of the earth where lightning occurs. There is evidence, which shows that, in Jupiter, lightning discharges exist. Furthermore, the discharges are said to be larger than the ones, which occur during lightning on earth (Gosline, 2005). There is a lot of information regarding lightning, but more research needs to be conducted. Concerns regarding radiation that is high energy, and which is obtained from lightning needs to be known. The latter is deadly to human beings and makes them be at harm. During lightning flashes, there is the production of nitrogen oxides, and it can cause global warming. For example, ball lightning needs to be research more upon, as it is not well understood. In conclusion, lightning is a fascinating phenomenon that needs to be known. People should have knowledge on how they can protect themselves from the effects of lightning. In turn, property and human life can be saved.
References
Rakov, V. & Uman, M. (2003). Lightning: Physics and Effects. Cambridge: Cambridge University Press.
Dwyer, R. (2005).”A Bolt Out of the Blue,” Scientific American, 292, 5, 2005, 64-71.
Gosline, Anna. (2005). HYPERLINK “http://www.newscientist.com/article/mg18624981.200” “Thunderbolts from space”. HYPERLINK “http://en.wikipedia.org/wiki/New_Scientist” o “New Scientist” New Scientist 186, 2498, 30–34.
