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Sunday, September 2, 2007

Striking back: lightning in the developing world


Striking back: lightning in the developing world


Scientists are battling to stop damage and death caused by lightning strikes in the developing world, reports Anuradha Alahakoon




In July this year, dark clouds and lightning stained the sky above Ushari Dara, a remote mountain village in northwestern Pakistan. After the storm had blown over, police reported that lightning had destroyed a dozen houses and killed up to 30 people.


In 1988, residents of Cibinong in West Java, Indonesia, reported lightning strikes on 322 days of that year; lightning had struck each square kilometre of land as many as 12 times.


And in Bangladesh, the metal roofing of shanties that provide shelter for the urban poor is an easy target for lightning. In 2003, 133 people died and 137 were injured after their homes were struck.


Despite these accounts, the dangers of lightning are not taken sufficiently seriously, say lightning scientists. Alarmed by the general lack of safety precautions in the developing world, some 30 experts met in Colombo, Sri Lanka in May this year to discuss how their countries could better protect themselves against future strikes.


The purpose of the forum was to raise awareness of lightning and lightning protection standards and, most importantly, to agree to exert pressure as a group on governments in developing countries to take lightning protection seriously.


"All the scientists are very much concerned about pressuring policy-makers in their countries to adapt relevant standards of lightning protection and educate the public," says University of Colombo lightning expert Chandima Gomes, currently lightning-protection advisor to the National Lightning Safety Institution based in the United States.



Making people aware


One of the biggest problems confronting lightning-protection scientists is the lack of awareness about the dangers of lightning.


For example, in Sri Lanka, where lightning kills around 50 people every year and damages US$2.5 million worth of property, people in neighbourhoods where deaths and injuries that have occurred from lightning still do not take precautions in subsequent lightning storms, a research team from the University of Colombo has found.



A tree destroyed by a
lightning strike
Credit: Wikimedia/Luis
Fernández García
But there are some initiatives in progress to raise awareness.


In Bangladesh, where literacy levels are only 30 per cent and therefore disseminating information on lightning safety is difficult, a project to increase awareness in rural villages - where deaths from lightning are frequent - has met with success.


A team of local experts, headed by Munir Ahmed from the nongovernmental organisation Technological Assistance for Rural Advancement, began a project in 2004 by using street dramas and folk songs to teach people how to protect themselves against lightning. Follow-up by the Lightning Awareness Centre in Bangladesh found that understanding about lightning protection had improved in those communities.


According to Gomes, lightning awareness centres, which act as a meeting place for scientists and the community, are also a good solution. At present there are about eight such centres operating in Asian countries, including in Bangladesh, Bhutan, India, Nepal, Pakistan and Sri Lanka. The scientists hope to build more such centres across the developing world.


Strengthening standards


Beyond lack of awareness, one of the principal problems the scientists identified at the forum is that many developing countries lack standards when it comes to producing, testing and installing lightning-protection devices such as lightning rods.


In Malaysia, many tall buildings are marked by lightning strikes, says Hartono Zainal from Lighting Research, a consulting body in Malaysia.


This is because some of the equipment used and marketed in Malaysia does not adhere to international standards, he says. So even though a considerable number of buildings have lightning-protection devices installed, many are not out of the danger zone.


The basic principle behind lightning-protection devices is that they provide a safe pathway - from the terminal above the building, through the conductor to the rod in the ground - for the lightning to earth, without destroying the structure or object it strikes.



Lightning in Marrakech,
Morroco
Credit: Wikimedia/
Blaise Thirard
Standards specify the size and materials that can be safely used for lightning-protection devices, how and where they should be installed on buildings, and how they should be tested.


One of the biggest problems is in the positioning of the lightning-protection rod, Zainal says. If it is not positioned correctly, it doesn't shield the building from lightning effectively.


"I found that 90 per cent of lightning strikes are at the corners of buildings. In most places when damage has occurred, the placement of the rod was wrong," says Zainal.


Coming up with solutions


One of the main goals for the scientists at the forum in Colombo was to find a way to reduce the number of deaths and the extent of injury from lightning.


Mladjen Curic, from the University of Belgrade in Serbia, believes that science may be able to provide part of the solution. Anti-hail rockets, which fire silver iodide into thunderclouds to suppress hail and protect agricultural crops, can also reduce lightning, he says.


The silver iodide seeded in the thunderclouds produce an excess of ice crystals, which cause the clouds to discharge their electrical potential, thereby reducing the likelihood of the lightning reaching the ground.


Curic's analysis showed that the rockets also reduced lightning by 50 per cent, providing protection over a large area for an extended period of time. He believes that this type of protection is much more effective than individual protection of objects.


Although his research is encouraging, a more immediate solution may lie in pressuring governments in developing countries to pay more attention to lightning protection.


The scientists at the Colombo forum hope this will come about through a policy document called the Colombo Declaration.



Scientists at the International
Roundtable of Lightning
Protection
Credit: SciDev.Net/
Anuradha Alahakoon
The Declaration is a set of guidelines and recommendations - developed and signed by the forum scientists - for governments to ensure that people have proper protection from lightning.


The document recommends increasing awareness among the public, enhancing technical skills among professionals, better protection of buildings, developing national standards and promoting local manufacture of lightning-protection devices with the help of financial grants and training.


One of the recommendations in the declaration is to build an international network for lobbying governments about lightning standards, particularly in African countries, where much work needs to be done.


"This kind of a policy document, which we can use to force policy-makers to adapt standards, is very important, and it will make positive impacts in many countries if rightly adapted," says Orabile Nanabu of the Botswana Technology Centre, representing Africa as a whole.


Sri Lanka has been nominated to house a planned international institute of lightning protection and safety. The country has the oldest lightning-research group - over 35 years old - in the developing world, based at the University of Colombo. Sri Lankan scientists pioneered the promotion of lightning awareness in the region and have close ties with the National Lightning Safety Institute in the United States.



"An international centre of excellence, where you have the technology and where any interested person can use the facilities at affordable cost will be good initiative to develop the field in future. This centre can host laboratories to test the lightning-protection devices cost effectively," says Chandima Gomes.




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