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Monsoons are back along with lightning
By K.R. Abhayasinghe
The second intermonsoon season during October and November follows the south west monsoon season in Sri Lanka and under certain conditions may even continue till mid-December.

During this intermonsoon season, we experience various weather conditions. Wind and temperature enhance the development of the cloud type called cumulonimbus and sometimes "anvil cloud"- so called because of its similarity to the blacksmith's anvil.

These clouds produce lightning, tornadoes and hailstorms. The cumulonimbus clouds develop between the altitudes 500 and 12 km under atmospheric conditions with strong upward movement of air associated with convection.

The lower part of a cumulonimbus cloud mostly consists of water particles and drops but the region above 5 km has mainly super-cooled water drops and ice. Since rain starts with falling ice particles, we may sometimes experience rain with ice (hailstorms). Fortunately, we are living in a tropical country where the low level temperatures are much above freezing temperature and the ice tends to melt before reaching earth, saving property from damage.

A lightning flash, after travelling about half a kilometre from the clouds selects the closest conducting path to come to earth before being neutralized. Therefore, the tallest objects are the best supporters of a lightning flash on its way to ground. In a natural environment, tall trees are lightning-attracters. Otherwise, conducting (metal) structures or objects (like communication towers, telephone and power supply lines and TV antenna) will attract lightning flashes. In the absence of such objects, buildings are vulnerable to direct hits by thunderbolts.

During bad weather conditions with thunderstorms, lightning surges may reach the inside of a building in a number of ways.

*Direct hit :

Single, considerably tall buildings are vulnerable to lightning flashes. Once lightning strikes a building, the current will pass through its conductive materials (reinforced iron in concrete columns and slabs, wiring, electrical circuit metal structures etc.) on its way to the ground if no safe way is provided for the purpose.

*Side flash:

A part or whole current of a lightning flash, which has hit a telephone or powerline or a TV antenna, may travel to a building via the electrical (metal) connection between the point of striking and the building. Depending on a number of parameters, a part of a lightning flash reaching a tall object (tree, tower) close by may spark to the conducting parts (concrete sun shade, concrete chimney roof or aluminium sheet) of a building even without any electrical connection.

*Step voltage:

The voltage difference between the feet resulting in a current spreading from a point of a lightning strike on the ground.

*Contact potential:

A shock occurs when there is contact with an object like a tree, building or conducting wire that acts as a part of a conductor of a lightning current.

Lightning is a natural phenomenon and, therefore, it is difficult to stop. But hazards caused by lightning could be reduced with precautionary measures, to pass the high current surge of a direct or indirect lightning current to earth safely. Some of them are:

*Install good earths for the electric circuit of buildings.

A lightning flash conducted through a power supply circuit may be as hazardous as a direct lightning strike. In buildings powered by the main power supply lines without the earth wire, this may be very serious.

* Use power surge diverters

Supply lines of power and communication can be interrupted by a power diverter which is capable of directing high currents - intruding into a building along supply cables as a result of a lightning flash-to the ground without allowing it to come into the interior of the building circuit.

* Installing lightning conductors/arresters

The direct hit of a lightning flash on a building is the most dangerous where lightning hazards are concerned. Solitary and tall buildings are the most vulnerable to lightning. The lightning rod, lightning arrester or conductor is the widely used device for the protection of buildings.

* In environments with thunderstorms,

- Electrical instruments should be disconnected from the main power supply.

- Television antennas should be disconnected from television sets and connected to properly installed earth rod. If this is not possible the antenna socket should be placed close to the earth outside the house.

- As far as possible, avoid handling/touching electrical instruments like refrigerators, electric iron metal frames, TVs and radios.

- Find shelter in a safe place in the open. If the time interval between lightning flash and thunder becomes less than 15 seconds, move quickly to a protected location as there is immediate danger of a lightning strike nearby.

- Try to avoid being in open areas like paddy fields, tea estates or play grounds. Avoid working in open air, holding metal tools like mammoties, knives and iron rods. lf this cannot be avoided, crouch down, singly, with feet together. Footwear or a layer of any non-absorbing material, such as a plastic sheet, offers some protection against ground currents.

- Do not seek shelter under or near isolated tall trees and in high grounds. If the vicinity of a tree cannot be avoided, seek a position just beyond the spread of the foliage.

- Avoid touching or standing close to tall metal structures, wire fences and metal clothes lines.

- Limit the use of telephones when a thunderstorm is overhead.
The writer is a Deputy Director,
Department of Meteorology

Rain or sun, home for them is where their wheelchairs or carts take them
Their wheels of life
By Ruwanthi Herat Gunaratne and Esther Williams
The man on the wheel chair was there last morning. He was there late last night and this morning too. In fact he has been on that pavement every time we passed that way in the past few months, in rain or sun. His shoulder-length grey hair is unkempt, a sign of what his life has become.

Didn't he have a home to go to, a family? Apparently not, for Linton is a cynic who has lost faith in every aspect of the social system. His life centres around his wheelchair.

To some extent, this is due to his amputated lower limb. At the prime age of 32, Linton came down with a bad case of diabetes which led to gangrene. This physical condition forced him to quit his job at the Model Farm.

His employers donated a tricycle-style wheelchair (self-operated) which keeps him mobile to a certain extent. His mobile home is parked on one side or the other of a by-lane, depending on the weather. Rain will see him under the big old "Mara" tree round the corner while sunshine sees him under the shady mango tree.

Homeless: Hemapala with his two children

Linton doesn't beg. But his presence evokes much sympathy from passersby who from time to time give him food packets. He goes to the Town Hall to wash each day and during the weekends he visits his brother in Narahenpita and takes the opportunity to bathe and freshen up.

Some time back he was accused of drug peddling and was taken in by the police. Having been found innocent, he is back on the road with no one to call his own.

Fifty- six -year-old K. Dianis of Matara is just around the corner. A polio victim, he is a cobbler and worked many years ago in Maradana. Owing to his disability, he chose to be out on the streets rather than trouble his relatives.

Like Linton, Dianis was given a wheelchair. The calliper and money he was promised never materialised. A devout Buddhist, Dianis goes to the temple once a week. Will his prayers ever be answered, we wonder. "Is there any place that you can think of, that I can go to?" he asks.

What would you do if you lived in a cart and a storm comes up? All your possessions and offspring have to be crowded in one small space. That is the daily ritual at the Hemapala household.

Two carts, one crammed with little toys, saucepans and other knick-knacks which you and I would call junk, while the other provides bedding for a family of four make up their home. The latter has no comfortable mattress, just a hard cardboard to line it. A grid woven from nylon cord is attached to the cart. "When it rains, I simply use the grid as a frame and cover the cart with polythene," smiles Hemapala.

His son Pradeep, aged six, attends a nearby school after which his main chore is to look after his baby sister, one-year-old Niluka. Every weekend consists of a trip to Thimbirigasyaya to wash and bathe. But why not try to earn a bit of money and provide the children with a roof over their heads? "That's what we did initially. We paid Rs. 1000 a month for two rented rooms. But the rent kept rising, and we just couldn't manage," Hemapala says.

Hemapala baby-sits while his wife is out in the mornings working - cleaning a furniture shop. She is paid Rs 1,000 a month. Once she gets home, Hemapala sets off, collecting discarded cardboard boxes from supermarkets and grocery stores, which he sells to vendors in Pettah.

Their daily earnings are enough to live on but not adequate to obtain housing. "But people around are so helpful. They give all kinds of goods and toys for the children. Yet, we are unable to utilize them as we have no space. Now we have got a room a little away from here at Rs. 300 per month to store our stuff." He lives in hope. But housing is still ages away.

What about medical attention? "That is really nothing to worry about. We are able to go to the General Hospital whenever a crisis pops up. The little one was quite sick the past few days and I think that it was due to the weather. But it blew over."

These people are not beggars. They are part of our society who lack the basic need of a roof over their heads.

There may be solutions for elders like Linton and Dianis, (see box) but as for Hemapala and family, the Social Service Department has no answer. "It is a complex problem. Land has to be acquired and built upon. If there was a disabled person amongst them we could have helped. Someone has to intervene positively," an official said.

Available options
What options do the homeless have? Where can they seek help? The Department of Social Services is quick to point out that there are facilities available for disabled and elderly citizens. "There are 154 homes for the disabled and 151 of these are run by Non- Governmental Organisations (NGOs)," an official said.

The procedure to get into these homes is simple enough. Each of the eight provinces has its own Social Service Officers. Any one wishing to obtain help needs to contact an officer from his/her province. And once the details have been documented he is then referred to the Director of the Province. If the relevant criteria is met he/she is placed in a home as soon as possible. Easier said than done though.

"Not everyone likes to enter a home which has strict rules and regulations. And most are unwilling to abide by them. Some feel that by checking into one they've signed an agreement to give up their freedom. We try to change this attitude, but it can be difficult at times," the official explained.

Helpage Sri Lanka also provides financial support to 158 elders homes and 100 day care centres for the aged around the country. K. D. Dharmawardene, the Publicity Officer of Helpage agrees with the Social Services Department that those seeking help feel that freedom is limited.

Their main focus is to encourage the elderly to live with their families and only in the worst cases do they advise that the elders should go into homes.


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