Dialah yang memperlihatkan kepada kamu kilat, untuk menimbulkan ketakutan dan keinginan dan Dialah yang menyusun awan yang berat.

Dan bertasbihlah petir dengan memujiNya, dan malaikat pun lantaran takut kepadaNya, dan Dia kirimkan halilintar (kilat) dan Dialah timpakan kepada barangsiapa yang Dia kehendaki, namun mereka masih membantah tentang Allah, padahal Dia adalah sangat pedih siksaan.
(Surah Ar Ra’ad :12-13)

Ahad, 28 Ogos 2011

Climate change worsens lightning threat


A lightning flash lights up the night sky in Putrajaya during a thunderstorm.

Despite the increase in lightning-related cases, awareness among Malaysians of the danger is very much lacking. In the last century, lightning has been recorded as one of the top three environmental-related causes of death in the world, reports LING POH LEAN

THE intensity of lightning is getting more severe due to global warming and climate change, according to the Meteorological Department.

Its deputy director-general Che Gayah Ismail said global warming causes the sea surface temperature to rise, producing more warm and moist air which was the main factor for thunderstorms.

"With the increased amount of warm moist air over the atmosphere, the intensity of thunderstorms and lightning will also become more severe," she told the New Straits Times.

Che Gayah said the Klang Valley recorded a higher number of lightning strikes compared with other areas.

Director of Centre of Excellence on Lightning Protection (CELP), Universiti Putra Malaysia associate professor Dr Mohd Zainal Abidin Ab Kadir said the greater exposure to the sun in countries at the Equator had sped up the vertical updrafts process (the process causing clouds to form), resulting in more rainfall.

"Malaysia is a tropical country which receives annual rainfall of between 2,000mm and 2,500mm. Global warming has probably increased the severity and frequency of thunderstorms.

"The increasing number of factories in the Klang Valley and the chemicals they are releasing also contribute to the thundercloud formation which lead to more thunderstorms in the Klang Valley."

According to the National Lightning Safety Institute of the United States, Subang, Bayan Lepas and Kluang are lightning prone areas with up to 180 to 200 thunderstorm days a year.

"But this is nothing new -- with the country's geographical location at the Equator, global warming and climate change -- we should prepare ourselves for more thunderstorms in the future," said Zainal.

Although Subang, Bayan Lepas and Kluang are prone to lightning, other parts of the country are also experiencing frequent thunderstorm days.

"There is no one area in the country that can be categorised as lightning prone due to global warming. I would say it is more unpredictable nowadays," said Zainal.

With global warming, Malaysia's average temperature has also increased by 0.8 degrees celsius (from 26.5 to 27.3 degrees celsius in the last 35 years.

A study by CELP revealed that many fatalities and damage caused by lightning had been reported between 2008 and last year, with 45 fatalities.

"The study showed that Malaysia was in the higher ranking for lightning injury cases in Asia with most of the fatalities during the month of May. Most of the cases were obtained from media reports, personal accounts, coroner reports and hospital admissions," said Zainal.

He said taking extra precautions could reduce the number of lightning injuries.

"Many are not aware of the damage that lightning can do and they take things for granted. The public should be more informed and be more aware that the country has a high number of lightning strikes."

He said many were neglecting safety measures to prevent lightning accidents.

"There is no way to prevent thunderstorms from happening, but we should at least take the necessary precautions. For instance, installing the right lightning protector on buildings."

Lightning typically occurs during thunderstorms. It happens when upward drafts of warm air (convection currents) carrying moisture interact against other water or ice particles high up inside the thunderstorm clouds, generating static electricity until it reaches an explosive threshold.

Lightning can occur throughout the year, but the number of lightning activities are higher during the inter-monsoon periods -- April, May, September and October.

Of late, the country has been experiencing showers and thunderstorms in the late afternoons and early evenings.

This, according to the Meteorological Department, is expected to continue over the next two to four weeks.

The department also said the west coast states of the peninsula -- southern Perak to western Johor -- would occasionally experience heavy rain and strong gusting winds during predawn and early morning, while Sarawak and western Sabah are expected to experience slightly wetter weather conditions.

With thunderstorms in the forecast, more lightning injury and death cases can be expected. Past records and newspaper archives reveal that several such cases occur almost every year.

In Malaysia, the incidents are no less. In November 2007, two oil storage tanks at the Shell Malaysia refinery in Port Dickson caught fire after they were struck by lightning.

In December 2006, a lightning strike near the Ipoh Selatan exit of the North-South Highway fried the computerised systems.

On April 11, 2009 a fire broke out at Putrajaya Hospital after it was struck by lightning. Staff evacuated all 14 patients in the orthopaedic ward before the ceiling collapsed.

This year alone several cases have been reported.

In February, a man died after he was struck by lightning while returning home after fishing for prawns at Sungai Perak in Teluk Intan and the following month a 24-year-old land surveyor died after he was struck by lightning while surveying the site near an oil palm factory.

And just last Monday, six Indonesians were killed and five others injured when they were struck by lightning in separate incidents in Shah Alam and Hulu Selangor.

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