Chandigarh, Thursday, November 18, 1999
Chandigarh, Thursday, November 18, 1999 |
Meeting
cyclones mid-way Understanding
the killers Century
of natural disasters predicted Block
on GM crops India’s
first computarium Cybersurfing with Amar Chandel Science Quiz |
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Meeting cyclones mid-way by Pravin Kumar ONE thing is clear after the super-cyclone that hit coastal Orissa on October 28 — that the state has no disaster management plan. Officials have now begun to feel that it may be time to construct cyclone shelters on the lines of those in neighbouring Andhra Pradesh. The cyclone left only concrete structures intact. Cyclones are no respecters of time or place, or of people who think “it can’t happen here”. The worst cyclone disasters happen in areas which are hit by cyclones once in 30 or 40 years—a time-frame long enough for people to forget that cyclone do occur. In Australia, for example, weather officials had been warning administrators of the futility of building houses, in the port city of Darwin, that could withstand 140 km/hour winds. People had forgotten the cyclones that hit Darwin in 1896 and 1937. Then, on Christmas Day of 1974, Cyclone Tracy ravaged Darwin: it cost $ 1 billion to rebuild the city. Cyclones are wind-systems of relatively low pressure which spiral inwards towards a centre in the lowest atmospheric levels. There is a net ascent of air which is pushed upwards by converging winds. Rising air is cooled by rising to higher altitudes, where pressures are lower; hence, cloudiness, rain snow are associated with cyclones. In the southern hemisphere, cyclones have clockwise wind-systems, and in the northern hemisphere, counter-clockwise wind systems. Cyclones which originate over tropical areas and contain no sharp air-mass contrasts, (or fronts) are called tropical cyclones. They affect the eastern equatorial portions of the continents. This includes the shores of the Bay of Bengal and the Arabian Sea. A severe tropical cyclone is also known as a hurricane. The highest speeds of a cyclone’s winds are in a circular band which begins at the edge of the central “eye” and extends out 32 or 50 kilometres or more; here velocities may reach 240 km/hour. The core, which is 8 to 32 kilometres across, is called the eye, because in this region the sky is often clear and the winds very light. This is why when a cyclone passes an area, strong winds are followed by a relatively calm interval of 15 to 30 minutes, after which there is a recurrence of strong gusts. A tornado is a special kind of violent local storm formed by rapidly rotating winds. SURGES As a cyclonic storm moves forward over the sea, it piles up huge waves or surges. The cyclone which hit coastal Orissa last month piles up surges 20 to 30 feet high. Giant waves pound and smash shore buildings, roads and bridges and topple trees and power lines. The greatest loss to life is by drowning, as torrential rains flood low-lying communities. Some areas are more cyclone-prone than others. From 1891 to 1970, the Eastern coast of India has been hit by cyclones 363 times, and the western coast, 98 times; on the western coast, coastal Gujarat is more cyclone-prone. For both coasts, the worst months, on the average, are October and November. Some cyclones move forward with great rapidity, while others move slowly or remain stationary. Obviously, it would be a great help if we could know when and where a cyclone would strike. But weather forecasts more than 48 hours ahead are difficult to make. Even with the most powerful computers, modelling the weather is a formidable task, for the equations governing the atmospheric process are not completely known or are so complex that they cannot be solved. However, polar orbiting and geostationary satellites, radar and aerial surveillance have made it easier to monitor the path of tropical cyclones. Modern satellites can view the movements of clouds with great precision and resolution (the capacity to distinguish between objects which are close together). By tracking the movements of clouds, it is possible to derive the strength and direction of winds over the lower and upper atmosphere. The present warning systems are unable to predict accurately the landfall of a cyclone. This may be 150 km on either side of the predicted area. Therefore, evacuation has to be done over a swath of 300 to 400 km width along the coastline. Generally, evacuation had to be done within 24 hours, which is costly in terms of manpower and resources. COUNTER-MEASURES Coastal cities are now at greater risk from cyclones because the population growth has been greater there. Measures to minimise cyclone damage can take three forms: *Long-term measures, which require 10 to 20 years and include building houses strong enough to withstand cyclones—this is cheaper than rebuilding destroyed houses—and land planning to keep the most vulnerable areas as green areas: *Medium-term measures, consisting of improvement in the communication network and the warning systems, and the establishment of emergency centres and cyclone shelters. *Short-term measures coming into play the moment a cyclone alert is received, including evacuation from vulnerable areas, and public health and sanitation precautions. Drills could be conducted regularly during the cyclone season at village, taluk, district and state level; fishing boats could be asked to carry transistor sets and deep-sea fishing craft asked to carry wireless to maintain regular communications with the coast. Andhra Pradesh has 1,041 cyclone relief shelters stocked with basic amenities along the coastal belt, beyond the inundation points—exclusively for those evacuated, each capable of accommodating 1,000 people. In addition, the government is promoting cyclone-resistant houses for the poor. It has also identified “pucca” buildings as safe places. Since the cyclone season is April-May and October-November, meetings are held in March and September to take stock of preparedness. A simple warning device for rural areas has been developed by the Directorate of Town and Country Planning (Tamil Nadu) and the Anna University of Technology, Chennai. This consists of a PVC ball mounted on a steel rod embedded in an iron pipe. Metal rings are held elastically in a coaxial arrange- ment, so as to make contact with the rod when it bends under wind load on the sphere; an electrical circuit is thus completed, setting off light and sound signals. This was designed for a wind-velocity of 35 knots. Later it was found that people needed two or three warning systems, rather than an outright danger signal, to prepare themselves. Hence, another model was developed, providing for two more wind velocities, of 30 and 40 knots. SYSTEMS ANALYSIS BASIS Disaster management, to be affective, has to be tackled on a systems analysis basis. For instance, if 10,000 persons are likely to be marooned in a particular area by a cyclone, a relief administrator will have to decide how many boats and how much food and medicine will have to be rushed to them, and how much priority has to be given to this area over contiguous areas. Any systems analysis should first identify the elements of the system. In this case, the elements would be as follows: *Inputs: Occurrence of the cyclone, affected people, tools required; *Outputs: number of lives and value of property saved; *the systems processor: the relief organisations; *the systems purchaser: the top management and the public; * the feedback control, which influences both the purchaser and the processor, consists to resource limitations, time constraints and uncertainty due to weather. A disaster management
system calls for a very comprehensive information system.
The data would include accurate projected population
figures, shelter locations and their capacity, and food
and medical facilities required. The information
processing will inevitably to be computerised. |
Understanding the killers WITHIN a span of just 10 days in October, the coastal areas in Orissa had bear the brunt of two cyclones. Coastal areas everywhere are under constant threat of cyclones in certain parts of the year when the surface temperature of ocean water is high. Other names for a cyclone are a hurricane used in the USA and Europe and a typhoon often used in west pacific. Cyclones often do extensive damage to human life and to property. The cyclone that hit Orissa on October 29 is an example of rare cyclone whose wind speed exceeded 250 km/hr. What is a cyclone and how is it created? Is it possible to forecast a cyclone in its formative stage and initiate measures to reduce the loss to human life? Cyclone are intense atmospheric vortices ( wind whirlpools) which derive their strength from warm surface waters of summertime tropical ocean. Cyclones can be mild or catastrophic. Their development is governed by natural factors and their movement determined by the flow in the surrounding undisturbed atmosphere. Damaging winds are concentrated within about 100 km of its centre ( eye of the storm). Damage capacity of a cyclone is dependent on the magnitude of the low pressure generated within the whirlpool and the associated wind speed. Cyclones have been divided into five categories depending on the wind speed within it and hence its damage capacity. Table I lists the five categories on the Saffir-Simpson scale.
Category 5 cyclones are rare. About 80% of all the cyclonic damage is caused by cyclones that fall under categories 3,4 or 5 and only 20% of all the cyclones come under these three categories. The first cyclone to hit Orissa on October 29 had a wind speed of 200 kph and the second one on October 29 had windspeed of 260 kph. The second one comes under category 5 and it did the maximum damage. A cyclonic condition is created whenever there is an exchange of heat between the warm ocean water at a temperature of around 30°C and the cold upper part of the atmosphere 17 km above the surface (called troposphere ) whose temperature is about minus 70° C . An air vortex at the sea level picks up water vapour from the ocean. As air full of water vapour ascends to the top of troposphere the water vapour condenses releasing heat energy which gets converted into mechanical energy. This energy is used by the air whirlpool to increase its speed i.e. to strengthen the vortex. Amount of mechanical energy released depends on the temperature difference between that of the ocean water and that of the troposphere. Further vortex induced upward mixing of cooler water from below the ocean surface can reduce the surface water temperature by a few degrees which, in turn, has considerable defect on the fastest wind speed attained. Another phenomenon that can change a mild cyclone into devastating one is “rapid deepening”. It is a self-feeding process in which the pressure in the eye of the storm falls quickly as wind speed increases leading to a still higher speeds and lower pressures. A cyclone path is easy
to forecast but not its intensity or damage capacity. At
present path forecasts made 24 hours before the cyclone
hits land are reasonably accurate. In another five years
it is expected that path forecasts can be made 48 hours
in advance. Since the path of a cyclone and the time when
it is likely to hit land can be predicted 24 hours in
advance the best that can be done to reduce loss to human
life is to take necessary precautions. Movement of people
to safer cyclone shelters is one step that should go a
long way in alleviating the misery. That requires a
coordination between the forecasters and the local
administration. Appropriate steps need to be taken for
reducing the magnitude of human tragedy caused by the
cyclones. |
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Century of natural disasters
predicted The world’s climate is heating up far faster than predicted, with the average temperatures in Europe soaring in the next century, according to new super-computer predictions. The increase will be faster than at any time in the world’s history. It will be far too fast for natural systems to adapt and will threaten world food production. The results of five years of work into die-back of tropical rain forests and increased microbe activity in soils caused by higher temperatures have startled scientists at the Hadley centre for climate change in Berkshire. Most of the Amazon rain forest will disappear, releasing millions of tonnes of extra carbondioxide into the atmosphere as the carbon in the wood is released as carbondioxide. Using the year 1850 as a baseline because it precedes the pollution effect of the industrial revolution, the Hadley centre expects temperatures to have risen by as much as 8°C (14°F) by the end of the next century over land masses like Europe - 2.5 degrees more than previously predicted. A 1C rise has occurred already. Geoff Jenkins, head of the climate change programme, says”basically the die-back of the forests and the increased warmth in the soil releases far more carbondioxide into the atmosphere than we had previously accounted for. The effect on climate and temperature is considerable.’’ Ute Collier, the World Wide Fund for Nature’s climate campaigner, says:”This is quite frightening, and should add urgency to these negotiations. “It’s not just the heating up - it is the extreme weather events which have trebled in number over the last 30 years. Events like Hurricane Mitch and the cyclone in India will happen more and more often. “Politicians have been dragging their feet over the last decade, the cuts proposed in carbondioxide emissions are just not enough. It is going to hurt most the poorest people in the world, the subsistence farmers who will no longer be able to feed themselves.’’ The computer modelling leader, Peter Cox, who had spent more than five years on the die-back of forests and release of carbondioxide from soil, said the previous internationally accepted calculation put the carbondioxide in the atmosphere at the end of the next century at 700 parts per billion. The new research showed this at 1,000 parts per billion, “a very significant increase.” This is three times the existing level and almost four times the level in 1850. Temperatures over the whole globe would rise an extra 1.5 degrees as a result but would be 2.5 degrees more over the land surface. Dr Cox says:”This is a preliminary finding which has not been peer reviewed so we need to be cautious and double check but we decided to release it because the results are so startling.’’ Until now scientists have believed that increased carbondioxide would increase forest growth and remove a lot of excess carbon dioxide. But scientists now believe this benefit will be outweighed by heavier losses in the tropics. . The result of heating up of forests is increased respiration of the leaves and a die-back of healthy growth. Running the computer models, scientists were startled that the Amazon forests began to disappear. Also badly affected would be southern Europe, parts of India and south-east Asia. At the same time microbes in the soil, which live on organic matter, increased their activity with the temperature—releasing significant extra carbon dioxide. Dr Cox says: “This
is already beginning to happen, especially in El Nino
years, when the forests become stressed because of lack
of rain and increased heat. In the Amazon there will be a
large-scale die- back leaving a very barren
state.’’ He said the temperature increase was
most marked at the poles. —The Guardian |
Block on GM crops No genetically modified (GM) crops will be grown commercially in Britain until at least the spring of 2003 to allow time for a panel of independent scientists to assess trial plantings and see whether they damage the biodiversity of the wider countryside, according to Mr Michael Meacher, Environment Minister. The agreement to hold off on commercial planting, made jointly with the GM industry, is a victory for the government’s official advisers, English Nature, and the environment lobby. They fear that heavy doses of insecticide and herbicide used on the GM crops will kill all other plants and insects, and that GM crops may cross pollinate with native plants. The government had originally intended to press ahead with commercial planting without any research into the environmental effects, but the outcry from the organic farming and green lobby caused it to think again. Mr Meacher is credited with finding a way out for the government by introducing the idea of a three-year programme of scientific trials. He says it was a voluntary agreement, which would “help us make a judgement not only on whether there is a downside to introduction of this new technology, but also about any potential benefits.” The trials will be held on spring and autumn-planted GM oil seed rape, maize, and possibly sugar beet. Plantings will be limited to between 20 and 25 fields per crop, about 200 hectares, spread out around the country. Mr Meacher said the sites of the trials would not be secret but he would be dismayed if “misguided activists seek to destroy these trial crops. They will be destroying the evidence of the effect of GM crops on biodiversity. They will be shooting themselves in the foot if they destroy the evidence which could get these crops banned,” he points out. At present, all the crops are destroyed when they seed and are not used for commercial purposes because no licences to use them as animal feed or in food have been granted. Stephen Smith, a spokesman for the GM companies, said if licences were granted during the three years, strict control would be exercised on how they were used. However, anti-GM campaigners were not satisfied with the three-year trial period. “We are not going to have directly commercially marketable crops for three years, but what happens when the three years is up?” said Patrick Holden of the Soil Association. “The government’s position seems to be that `British biotech plc’ needs to get a bite of the GM cherry as quickly as possible.” —The
Guardian |
India’s first computarium India may soon have its first computarium, a museum designed to initiate children into the wonders of the information technology (IT) era through interactive gadgetry and virtual reality experiences. Work on the Rs 40 million computarium is expected to begin in January 2000 with sponsorship from the biggest names in the IT business. The project, which is being undertaken by a trust consisting of the Centre for Development of Advanced Computing (C-DAC), the Department of Science and Technology, Indian telecom industry and the chief secretary of Karnataka, has already been allotted five acres. Organisers are confident that going by the response to the just concluded IT expo, Bangalore IT.Com, sponsorship for the project will pose no problem. “The response from school children as well as IT companies at IT.Com has been so marvellous that the computarium would become a reality,” says Sugandha S. Raj, programme director for the project. The concept is to provide “fun” while giving exposure to information technology, creating a computer generated atmosphere to make learning mathematics or physics or even alternate learning like yoga, fun for children of all ages. The squeals of delight from the computarium pavilion at IT.Com was evidence of the response from children, mainly from the rural areas, who flocked to the show. The hi-tech fun-filled guided tour for children covered the Vedic period to bionic computers. IT majors Intel, Pentafour, Texas Instruments, Apple, Novell, and SchoolNet provided the inputs for the two-hour daily workshop that made children from 40 urban and rural schools as well as 700 teachers, mainly from the rural areas, experience technology. The computarium, says Sugandha Raj, would customise its operations for local children who do not have exposure to the English language or computers. “There are about 5,700 schools in this city. But only 80 of them have computers. The computarium will design bilingual programmes because what came across very strongly was that language did not come in the way of the children understanding the subject,” she says. The computarium would not only have films showing the growth of information technology but also the cockpit, submarine or aircraft simulators and hi-tech gadgets like the eye tracker for the mentally challenged and elbow, knee and shoulder mouse systems for the physically challenged. About 200 IT companies have agreed to contribute to the computarium. And, after IT.Com, companies like Epson and IBM and several others have responded positively. “Our request to them is share their experiences with us. If you are a chip manufacturer, give us a film on the how and when of it. We are not seeking money. We want inputs,” Raj says. The trust, which runs on
corporate sponsorships, is planning to look at similar
ventures in other states once the museum is commissioned
— IANS |
Cybersurfing with
Amar Chandel VAGARIES of the DoT lines have kept this column in limbo for a long long time. Now that we have got our own line, it is hoped that the ordeal will be over. Let us get back into action with a few utility items. Sonara Technologies has come up with its Display Mate which helps you achieve better image quality and picture quality on any computer monitor, LCD display, video projector, TV, HDTV or any type of display device that can be connected directly or indirectly to a computer. The 129.5 kb device helps you select the best monitor and set it to the optimum performance through step by step instructions. Another useful device is Dr Cleaner which searches seamlessly for files that may be occupying valuable disk space and you can then remove them conveniently. But it has a size of 1.6 mb itself. Both of these can be downloaded from www.snap.com or several other search engines. * * * One website which most car lovers are likely to love is www.cybersteering.com. It is large treasure trove of information on cars. There are separate sections on James Bond cars (and their weird features), fastest car (Lamborghini Diablo ’99 has been given the top honours with the fastest top speed of 340 kmph (0 to 100 kmph in less than four seconds), Herbie the lovebug and Batmobile. But for a passing by enthusiast, the most fascinating section is the trivia snippets. Who was the first Indian to own a car? How did Mercedes, Toyota and some others got their names? To know the answers, visit this section. * * * The number of Mac owners is suddenly on the upswing. For those who want to keep in touch with the latest in the world of Apple Macintosh computers, http://macworld.zdnet.com is a good link. The online version of the popular magazine gives the latest information, including in-depth articles, reviews, comments and news about the happenings in this world. * * * The old Beeb retains its
special place in the heart of news-hungry readers.
www.bbc.co.uk/home/today not only gives the latest news
but also has a lot of information about the various
features that are broadcast by BBC. It also has its own
web guide, where the site of the day is featured. |
Science Quiz 1. Who instituted Nobel Prizes? What did he invent that enabled him to amass huge wealth for instituting these awards? Which organisation makes selections for these annual awards? 2. Name the winners of the 1999 Nobel Prize in physics. To which field of physics have they made their contribution? 3. Electronic paper, or e-paper, may make paperless offices a reality in the near future. It would be a paper-thin digital display sheet that could be written on, folded, put into a pocket and re-used. What physical quantity will a pen use to write on it instead of ink? 4. RDX, mixed with other suitable materials, is used for terrorist activities. It can be cast into any shape and its low vapour pressure makes it less prone to detection by electronic devices. What is its full common name? What is the chemical name of this white crystalline powder? 5. We know about the nine planets revolving around the sun in our solar system. Which objects in this solar system are called “minor planets”? 6. Of all the living invertebrate animals, which species are the largest in number? Which group of these species constitutes the largest as well as the smallest sized animals? 7. Which phenomenon is used by musicians to ensure that two musical instruments are in unison, that is, they vibrate with the same frequency? 8. Name the African bird that builds the largest roofed nest and takes about two months to make this huge nest. 9. Some bacteria absorb fumes emitted by explosives and become luminescent. What is this method of detecting explosives called? 10. On December 1st, the world will observe a day to focus attention on one of the most dreaded diseases. What is this day called? Answers 1. Swedish chemist
Alfred Berahard Nobel; dynamite and other explosives;
Royal Swedish Academy of Sciences 2. Dutch physicists
Gerardus T Hooft and Martinus Veltman; Particle physics
3. Electrical voltages 4. Research Developed Explosive;
Cyclotrimethylene-trinitramine 5. Asteroids, mostly
moving between the orbits of Mars and Jupiter 6. Insects;
Beetles 7. Beats 8. Hammerhead stork, also known as
hammerkop 9. Biosensing 10. World Aids Day. |
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Feel the music Higher
antibiotic potency A team comprising chemistry professors Hirokazu Arimoto at Shizuoka University and Daisuke Uemura at Nagoya University; and Tomoya Kinumi, research fellow at the National Institute of Infectious Diseases in Tokyo, prepared the new antibiotic polymer from a monomer. They showed that an alcoholic solution of the polymer was up to 60 times more potent than vancomycin antibiotics against vancomycin-resistant enterococci (VRE), reports Chemical & Engineering News. Vancomycin is a drug of last resort against bacteria such as Staphylococcus aureus. The emergence of VRE and the possibility of transferring this resistance to S. aureus is currently a major cause of concern for doctors. Thermoplastic
nanocomposites The researchers have discovered that by reacting wood pulp fibres in a solvent medium that not fully penetrate the fibres, and then hot-pressing the partially modified pulp fibres at elevated temperature, a semi-transparent polymer sheet is formed which is actually a nanocomposite of cellulose esters and unmodified cellulose. The wood pulp raw material starts out looking like pulled apart tissue paper. After the solvent is added, the fibres look much the same, but actually the surfaces of the microfibrils within each wood pulp fibre can flow on melting like plastics. Odour-free
clothes The formulation can kill
more bacteria and viruses than other “biocidal”
cotton, according to the researchers from a Seattle-based
company, HaloSource, that is developing the product. |
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