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Component-I (A) - Personal Details
Component-I (B) - Description of Module
Items Description of Module
Subject Name Geography
Paper Name Disaster management
Module Name/Title Disaster Management for Thunderstorms and
Lightning
Module Id 28
Pre-requisites
Objectives
Keywords
Role Name Affiliation
Principal Investigator Prof. Masood Ahsan Siddiqui Department of Geography, Jamia Millia Islamia, New Delhi
Paper Coordinator, if any Dr. Rajnish Ranjan Vice president, Skymet
Content Writer/Author (CW) Dr. Rajnish Ranjan Vice president, Skymet
Content Reviewer (CR) Prof. Masood Ahsan Siddiqui Department of Geography, Jamia Millia Islamia, New Delhi
Language Editor (LE)
Module 28. Disaster Management for Thunderstorms and Lightning
Learning Objective
To understand the phenomenon of Thunderstorm and Lightning
To explore the impact of lightning
To get to know the global and national scenario of lightning
To understand different preventive measures
Phenomenon of thunderstorm and lightning
A thunderstorm is a storm associated with lightning and thunder. They are typical atmospheric
phenomena and tend to be highly localised. It is generated within the clouds and thus prevention is
beyond the human control. From a purely disaster management point of view, the main hazard is
lightning and not the thunderstorm. Thus, in this module we shall focus more on the hazards caused
due to lightning.
Thunderstorm forms within a warm, moist air rising in an unstable environment. As long as rising air
becomes warmer (less dense) than surrounding air, there is upward-directed buoyant force acting
on it. The warmer the air as compared to its surroundings, the greater the buoyant force and the
convection. The triggering forces needed to start air moving upward can be one of the following (C.
Donald Ahrens, 2016)
1) Random, turbulent eddies that lift small bubbles of air
2) Unequal heating at the surface
Rationale
On account of varied hydro-meteorological condition, India is exposed to varied kinds of
hazards throughout the year. Thunderstorms and Lightning is one of them. Despite having
localised and varied spatial and temporal dimensions, thunderstorms associated with
lightning pose high risk. People as well as infrastructure are at risk in varying degrees.
Thus, a culture of disaster management is necessary to minimise the risk of lightning. This
can be done through a set of preventive measures.
3) The effect of terrain (such as small hills) or the lifting of air along shallow boundaries of
converging surface winds
4) Large-scale uplift among mountain barriers and rising terrain
5) Diverging upper-air level winds, coupled with converging surface winds and rising air
6) Warm air rising along a frontal zone
Normally, combinations of these phenomena triggers with vertical wind shear to generate severe
thunderstorm.
Lightning is a discharge of electricity, a giant spark which usually occurs in the mature thunderstorms
(C. Donald Ahrens, 2016). Lightning may take place within a cloud, from one cloud to another, from a
cloud to surrounding air or from a cloud to the ground. Lightning results from a strong separation of
an electric charge that builds up between the top and bottom of cumulonimbus clouds (Donald
Hyndman, 2011). Air carrying water droplets and ice particles move towards the top of the
cumulonimbus clouds where they clash with the downward moving ice particles or hail. In this
process, strong positive charge usually carried by top of the cloud interacts with the lower part of
the cloud which carries strong negative charge. Negative and positive charges attract one another; a
negative electrical charge may attract the positive-charged cloud top or to the positive-charged
ground. This generates electrical charges in terms of millions of volts. At one point of time the
electrical resistance in the air cannot keep these opposite charges separate from each other; it
results in positive and negative regions joining with an electrical lightning strike. A person standing
on the ground will always see ‘Lightning’ first and then hear the ‘Thunder’ sound though both occurs
at the same time. This is due to the fact that light travels at a speed of around 300,000,000 metres
per second while sound which travels at a speed of 340 metres per second. So the light is visible
before the lightning sound.
Impact of Lightning
The critical impact of lightning is death and injuries, but more than that, economic damages arising
out of lightning are worth mentioning. Lightning causes damages worth of billion rupees in the
Housing, Agriculture, Industrial and Public Sectors (Illiyas, Mohan, Mani, & Pradeepkumar, 2014).
Lightning strikes can injure humans in the following ways-
i. Direct Strike – The person falls in the path of the lightning strike. Due to the passage of
enormous energy through the body, this kind of event results in severe burns and
damaged nervous system, and is often fatal.
ii. Contact Injury – Occurs when the person touches any object which was electrified by
the lightning strike.
iii. Side Splash – Branches coming off from the primary flash channel injuring the person.
iv. Blast Injuries – Occurs when the person is impacted by the blunt force trauma of the
lightning strike
Step Potential –Once the discharge occurs, the earth surface charges race towards the spot of
lightning strike. Ground provides high resistance. To avoid this, the charges follow a better
conductor ( e.g Human body ) in case it is present in the path. “The near instantaneous rate of
discharge causes a potential (difference) over distance, which may amount to several thousand volts
per linear foot. This phenomenon is responsible for more injuries & deaths than the above three
combined.” (NDMA, 2015)The discharge also produces electromagnetic pulses which can damage an
artificial pacemaker and affect normal biological processes.
If there is a direct lightning strike to a structure, then the types of damages include:
Injuries to living being by electric shock as a result of touch and step voltage.
Fire, explosion, mechanical and chemical reactions as a result of the physical effects of
the lightning discharge
Failure of electrical and electronic systems due to surges
If there is a lightning strike near a structure, then the types of damages include:
Failure of electrical and electronic systems due to surges
If there is a direct lightning strike to an incoming line, then the types of damages include:
Injuries to living being by electric shock as a result of touch and step voltage.
Fire, explosion, mechanical and chemical reactions as a result of the physical effects of
the lightning discharge
Failure of electrical and electronic systems due to surges
If there is a lightning strike near an incoming line, then the types of damages include:
Failure of electrical and electronic systems due to surges
The kind of losses resulting from these types of events includes loss of human life, loss of service to
the public, loss of cultural heritage, loss of economic value etc. While loss of human lives include
injury or death of a person , loss of economic value primarily includes loss of agricultural properties
likes farms, animals etc. are referred.
Individuals surviving the immediate effects may develop “Lightning Syndrome”. It is characterized by
unconsciousness, temporary impairment of central and peripheral nervous system functions,
conductive deafness and skin burns etc. (Chattopadhyay & Das, 2009).
People involved in agricultural activities, grazing animals, forest workers, homeless and nomads are
particularly vulnerable to lightning.
Hailstorm is another phenomena associated with thunderstorms. Hailstones are solid chunks of ice
having varying size, which is produced during thunderstorms. It does not induce human life loss or
major injuries, but is considered as major hazard in India due to the economic losses associated with
it , mainly in the agricultural sector.
Global Scenario of Lightning
Lightning is a common occurrence, especially in tropical and sub-tropical regions which results in the
massive number of deaths per year. It occurs intermittently throughout the year. Global estimates
range from 6000 to 24000 fatalities per year due to lightning strikes (Singh & Singh, 2015). But it is to
be noted that there has been little systematic collection of information on lightning deaths in many
regions of the world making it difficult to give correct estimates.
The below mentioned figure -1compares the rate of lightning fatalities in India with other countries
of the world. The number of fatalities have been taken from different publications all over the world.
According to the figure, the number of lightning deaths in different nations for certain periods of
time has been recorded. The time period is non uniform due to the lack of data, but it provides a
rough estimate of the average annual death rate per million people. As per the figure we can see,
that for a given period the lightning fatalities occurring in India, China and United States of America
are 5259, 5033 and 3239 respectively. But highest number of average annual death rate per million
people is of Swaziland with 15.5, followed by Zimbabwe at 13.4. In comparison to Swaziland, India
have very low average annual death rate per million people with number of 0.25.
Lightning in the India context
The Map-1 above illustrates the average number of thunder and lightning days and relative hazard
priority over major Indian cities (source- BIS-2007) We can observe that cities from Northern and
southern part of India are marked with High and Very high hazard. Parts of Gujarat, Madhya
Pradesh, Chhattisgarh, Maharashtra, Telangana and Andhra Pradesh fall under very low and low
hazard zone for thunderstorm and lightning.
The investigation shows that a total of 5259 fatalities were observed as a result of lightning strikes
occurred from the year 1979 to 2011. The average fatality per year in India is 159. States like
Maharashtra, Kerala, West Bengal, Uttar Pradesh and Karnataka are having the highest lightning
casualty risk.
The Map-2 above shows the rank of lightning-related fatalities by a step of 5 in rank. The west
central India demonstrates the largest number of fatalities, followed by central northeast India,
Peninsular India and Northeast India. The spatial variation also shows that lightning fatalities are
higher than over western states and least over northwest India and hilly states.
The number of fatalities due to lightning varies across seasons as well. In the Monsoon season (June-
September), 57% of lightning fatalities were recorded, while 31% of lightning fatalities occurred in
summer or Pre-Monsoon (March-May) phase. Post-Monsoon (October-November) and Winter
(December-February) corresponds for relatively small number of fatalities (Singh & Singh, 2015)
It is interesting to note that during the year 1979-2011, far more males (89%) than females (5%)
have been killed by lightning flashes in India. The reason attributed to this is the relatively higher
work participation by males in traditional tasks like agricultural work, construction work etc. and
more exposure to outdoor activities and recreational activities.
Date and Year Place and state Number of victims
11 August 2010 Sapaul (Bihar) 52
18 July 1996 Hazaribagh (Jharkhand) 39
28 September 2004 Nashik (Maharashtra) 31
25 June 2006 Gwalior (Madhya Pradesh) 30
13 March 2007 Balia and Basti (Uttar Pradesh) 28
6 July 2000 Balia (Uttar Pradesh) 27
6 June 2007 Basti and Gonda (Uttar Pradesh) 25
30 June 2007 Raigad (Maharashtra) 25
19 June 2006 Hingoli (Maharashtra) 24
27 June 2010 Yavatmal (Maharashtra) 24
The above mentioned figure-2 highlights the top ten lightning incidents each of which recorded
fatalities of more than 20 people. The largest fatality numbers were recorded in the tragic incident
that occurred in Supaul district of Bihar state, which killed 52 people and injured 12 others on 11
August 2010. The maximum number of lightning induced fatality incidents (involving 20 or more
people) occurred in state of Maharashtra (four times) followed by Uttar Pradesh (three times).
The Figure-3 above shows that lightning is responsible for at least 10% of the total deaths caused by
hazards in India according to National Crime Records Bureau data. According to another study, 29%
of disaster induced deaths in the last 45 years (1967-2012) have occurred due to lightning compared
to 18% by floods. At least 2,000 deaths were associated with lightning every year since 2005.
In spite of the massive impacts of lightning, the severity associated with the hazard and its risk
perception is low. Lightning is very localised and isolated event. Deaths from lightning are normally
single event and it affects very few people at the same place at the same time, unlike hazards of
earthquake, flood, cyclone etc. Thus, in spite of the total death toll of lightning being very high, it
often misses to grab attention due to its dispersed nature.
Lightning Hazard prevention mechanisms
After observing various dataset highlighting the risk of lightning in India, it is necessary to talk about
the preventive measures for lightning. Some of the important measures are as under -
1. Early Warning System
The Early Warning System (EWS) is very essential in disaster risk reduction. The essential
components of Early Warning Systems are risk knowledge, monitoring and warning services,
dissemination and communication of warning and response capability. Thus in order to save lives
from lightning it is necessary to develop early warning system and moreover dissemination of early
warning information .
Case study of Jharkhand
During the year of 2008-2010, a pilot project of Monitoring lightning and thunder was carried out in
the state of Jharkhand. Lightning detection centres were established at different places such as RAC
Campus, ZRS Chianki, ZRS Darisai, KVK Jagannathpur, ZRS Dumka and Gauria Karma Unit. A mobile
lightning detection unit was also established. Boltek LD-250 sensors of 500 km resolution were used
for the detection of lightning. Based on this study, an early warning system was established. With
the observation from lightning detection centres on-time warning was issued through various means
such as Hooter, SMS, Mail, Television, Radio and Agromet advisories. An Android app named
Weatherbug was also used to issue 30 minutes to 3 hours’ advance warning against lightning. This
was a significant step towards averting lightning risks.
2. Installation of Lightning Arresters
Lightning Arresters are devices that arrests lightning before its formation and hence there is no
sound and light. Based on the expected intensity of lightning, the lightning arresters are installed in a
series to make an area lightning safe.
Again in the state of Jharkhand, the Building Bye Laws (2016) makes it mandatory for all G+2 and
above buildings to install lightning arresters.
3. Lightning Protection System
Air Termination System, Down Conductor System and Earth Termination System are widely used as
Lightning Protection Systems in the country . Air Termination Systems consists of Rods, Spanned
Wires and cables or Meshed conductors as stand-alone or combined as required. Air Terminal is a
type of strike termination device intentionally installed for the purpose of intercepting lightning
flashes (LIGHTNING PROTECTION, 2016)
While using the Air Terminal method, Air Terminal Tip must be located at not less than 10 inches
above the protected object, if the internal spacing is not more than 20 feet between air terminals.
Figure 4 and 5 illustrates the typical roof
protection for buildings with flat roof. Air
terminal spacing can be either 20 or 25 feet
pending on terminal height. Perimeter and down
conductors, with connections to ground rods are
also shown.
Figure 4: Air Terminal, Source (LIGHTNING PROTECTION, 2016)
4. Rolling Sphere Design
This method uses an imaginary spherical ball with 150-foot radius that rolls over the building
structure touching only the tips of air terminals mounted on the roof. This dimension is based on the
fact that lightning strike distance near the surface of the earth is about 150 ft. or less. When using
spherical shape to determine the zone of protection for the building all possible placements of the
sphere on the structure shall be considered for terminal placement. A protected building that is
more than 150 feet high will provide protection for lower elevation roof areas of adjacent or
connected structure when the lower structure roof is protected by the arc of the sphere that is
tangent to the side of the protected building and to the earth. This method has been shown in the
figure 9.
Figure 5: Air Terminal, Source (LIGHTNING
PROTECTION, 2016)
Figure 6: Rolling Sphere Method, Source: (LIGHTNING PROTECTION, 2016)
5. Protective Angle Method
The Protective Angle method is based on a ratio of upper building height and size to lower building
area height and size with the location and placement of air terminals. If not more than 25 feet to the
lower eaves, a 2:1 ratio (2 horizontal feet of building coverage for each vertical foot in elevation) can
protect the lower portion of a building or out to the first air terminal location on a large roof
structure. If not more than 50 feet to the eaves or to the perimeter air terminal location on a higher
flat roof, the lower roof is protected by the higher roof in a 1:1 ratio (1-foot horizontal coverage for
each vertical foot from the upper structure). This ratio would also cover the larger flat roof to the
first air terminal based on the height ratio. Figure 10 shows the application of this ratio.
Figure 7: Application of Protective Angle method, Source-(LIGHTNING PROTECTION, 2016)
Non-structural measures to minimize lightning risks include-
First Aid
Majority of deaths in lightning takes place due to anoxia. Thus, first aid in the form of Cardio
Pulmonary Resuscitation (CPR) immediately after the strike till proper medical is care available may
prevent loss of life. Knowledge of CPR among the common man is necessary in cases of emergency.
Imparting the knowledge of CPR to common masses is important part of enhancing community
preparedness to lightning.
Community Preparedness
To develop a culture of safety and resilience, Community Preparedness is extremely necessary. The
risk of lightning is not uniform across the country. Thus, it is necessary to follow different means to
increase and enhance community preparedness. This can be done through different strategies
proposed below.
a) In areas having lower level of literacy, the awareness program should be conducted by the
people who are familiar with local languages and customs. The message of dangers
associated with lightning and lightning safety should be conveyed through songs, dramas,
story-telling etc. at the places, where people gather often. Display of posters with photos of
lightning impacts and safety rules can also be done.
b) For communities with medium literacy rate conducting public seminars and demonstrations
in local language and use of posters with written safety tips should also be used. Seminar
should consist of basics of lightning, lightning safety and protection and first aid such as CPR.
c) In areas with high literacy rate such as urban centres awareness program can be
incorporated with web based information and educational programs which are ICT enabled.
d) Incorporating the lightning safety in the School curriculum will streamline the knowledge at
a formal level and help in dissemination of information.
A judicious mix of above recommended strategies will definitely help in increasing community
preparedness and building a culture of safety.
Lightning study Centre (LSC)
In order to prevent losses due to lightning incidents in the country , it is of urgent necessity to
establish a dedicated Lightning Study Center (LSC) that could actively involved in conducting
research, awareness programs and information dissemination for lightning protection. The LSC will
be able to work with international institutions/individuals and other regional organizations in close
coordination. Through collaboration with entrepreneurs, LSC will be able to provide solutions of
lightning protection at various levels. Sensitization of bureaucracy and engineers regarding lightning
risks, lightning safety and protection can also be conducted by LSC.
Precautions
Following precautions are necessary to be followed during the event of thunderstorm and lightning
(Donald Hyndman, 2011).
Take shelter in an enclosed building. Its metal plumbing and wiring will conduct the electrical
charge on the ground. So, better to stay away from it.
Do not touch anything that is plugged in.
Stay away from open water. Also do not take bath or wash dishes as water is good
conductor of electricity
Stay away from open fields. It can be harmful as lightning can travel along the ground for
about 20 metres.
Stay away from trees, power poles or any other tall object. Rather than staying under a tall
tree, taking cover in low bushes well away from tree is better plan.
Stay away from metal objects, such as fences, umbrellas, farm equipment’s and outside of
cars and trucks. Be aware of overhead power lines.
While driving, stop the car in a safe spot. Stay inside a car with the windows closed and do
not touch any metal.
Installation of light protection system is necessary to protect from any direct lightning.
The following Do’s and Don’ts are essentially required for any community affected by lightning –
Do’s and Don’ts on Thunderstorm and Lightning
If you are outside
1. Go Inside when Thunder Strikes
2. Stay Individual , Stay Safe
3. Do not lie down in open , Rush to a Safe Shelter
4. If caught in Lightning, Bent down yourself in a rounded shape
5. Keep away from Trees or open areas , prevent disasters
6. Mountain tops or Highlands are dangerous during thunderstorm, get down immediately
7. Flying Kites or playing in open areas may be dangerous! Avoid doing so.
8. Avoid using Umbrella, Fishing Rods, Metal Sticks etc.
9. If you are in water or Swimming pool during thunderstorm, immediately rush out .
10. If you are in Boat/Steamer, go ashore to a safe shelter
If you are Inside
1. It’s dangerous to use plugged in Telephone or Electric /Electronic Appliances –Avoid using
them during lightning and thunderstorm.
2. Avoid using all the electric appliances or wired gadgets during thunderstorm and lightning .
3. Install ‘Lightning Conductor’ in your house/office/other installations . It can save you .
4. Moving Barefoot inside the house may be dangerous ! wear rubber slippers.
Institutional Mechanism to address Lightning and Thunderstorms in India
Certain initiatives have been undertaken in the institutional frameworks to address risks of lightning
and thunderstorms.
Indian Standard Code of Practice for Protection of Buildings and Allied Structures against Lightning
outlines the technical aspects of lightning. It mentions how to assess risk of lightning strike and
provides guidelines to determine if a structure is in need of protection. It also provides guidance on
good building practices to prevent harm.
Currently, lightning is still not recognized as a major disaster. It is not present in the national list of
notified hazards, in spite of the alarming number of lightning deaths. It falls in the state notified
hazard list of only select states, like Jharkhand. As such the reporting of lightning events and ensuing
compensation mechanism is not streamlined. Concentrated efforts to prevent and mitigate the risks
are also in a nascent stage.
