Monsoon arrival in Asia witnesses increased frequency of lightning strikes. During each monsoon many persons  lose their life because of it. A lightning strike is an electric discharge between the atmosphere and an earth-bound object. They mostly originate in a cumulonimbus cloud and terminate on the ground, called cloud to ground (CG) lightning. A less common type of strike, called ground to cloud (GC), is upward propagating lightning initiated from a tall grounded object and reaches into the clouds. About 25% of all lightning events worldwide are strikes between the atmosphere and earth-bound objects. The bulk of lightning events are intra-cloud (IC) or cloud to cloud (CC), where discharges only occur high in the atmosphere. A single lightning event is a flash, which is a complex, multi-stage process, some parts of which are not fully understood. Most cloud to ground flashes only strike one physical location, referred to as a termination. The primary conducting channel, the bright coursing light that may be seen and is called a strike, is only about one inch in diameter, but because of its extreme brilliance, it often looks much larger to the human eye and in photographs. Lightning discharges are typically miles long, but certain types of horizontal discharges can be upwards of tens of miles in length. The entire flash lasts only a fraction of a second. Most of the early formative and propagation stages are much dimmer and not visible to the human eye. Lightning strikes can produce severe injuries, and have a mortality rate of between 10% and 30%, with up to 80% of survivors sustaining long-term injuries. These severe injuries are not usually caused by thermal burns, since the current is too brief to greatly heat up tissues;instead, nerves and muscles may be directly damaged by the high voltage producing holes in their cell membranes, a process called electroporation. In a direct strike, the electrical currents in the flash channel pass directly through the victim. The relatively high voltage drop around poorer electrical conductors (such as a human being), causes the surrounding air to ionize and break down, and the external flashover diverts most of the main discharge current so that it passes around the body, reducing injury. Metallic objects in contact with the skin may concentrate the lightnings energy, given it is a better natural conductor and the preferred pathway, resulting in more serious injuries, such as burns from molten or evaporating metal. At least two cases have been reported where a strike victim wearing an iPod suffered more serious injuries as a result. However, during a flash, the current flowing through the channel and around the body will generate large electromagnetic fields and EMPs, which may induce electrical transients (surges) within the nervous system or pacemaker of the heart, upsetting normal operations. This effect might explain cases where cardiac arrest or seizures followed a lightning strike that produced no external injuries. It may also point to the victim not being directly struck at all, but just being very close to the strike termination. Another effect of lightning on bystanders is to their hearing. The resulting shock wave of thunder can damage the ears. Also, electrical interference to telephones or headphones may result in damaging acoustic noise.

Epidemiology

One estimate is that 24,000 people are killed by lightning strikes around the world each year and about 240,000 are injured.Another estimate is that the annual global death toll is 6,000. According to the NOAA, over the last 20 years, the United States averaged 51 annual lightning strike fatalities, placing it in the second position, just behind floods for deadly weather. In the US, between 9% and 10% of those struck die,^[10] for an average of 40 to 50 deaths per year (28 in 2008).^[11] The chance of an average person living in the US being struck by lightning in a given year is estimated at 1 in 960,000. In Kisii in western Kenya, some 30 people die each year from lightning strikes. Kisiis high rate of lightning fatalities occurs because of the frequency of thunderstorms and because many of the areas structures have metal roofs. These statistics do not reflect the difference between direct strikes, where the victim was part of the lightning pathway; indirect effects of being close to the termination point, like ground currents; and resultant, where the casualty arose from subsequent events, such as fires or explosions. Even the most knowledgeable first responders may not recognize a lightning related injury, let alone particulars, which a medical examiner, police investigator or on the rare occasion a trained lightning expert may have difficulty identifying to record accurately. This ignores the reality that lightning, as the first event, may assume responsibility for the overall and resulting accident. Direct strike casualties could be much higher than reported numbers. ..... .... Login with Google and support us
Thanks