Plus
 

Under a cloud

 

Contents


Under a cloud
Save Asia from toxic haze, appeal scientists
LONDON - The toxic haze hovering over South Asia much of the year is threatening the lives of millions of people in the region and could have an impact much farther afield, according to a UN-sponsored study.

The world body said the haze, a toxic cocktail of ash, acids, aerosols and other particles, is damaging agriculture from Afghanistan to Sri Lanka. The lives of millions of people are at risk from drought and flooding, partly because rainfall patterns have been radically altered, with dire implications for economic growth and health, according to the study.

"We have an early warning. We have clear information, and we already have some impact. But we need much, much more information," UN Environment Programme chief Klaus Toepfer told a news conference. "There are also global implications, not least because a pollution parcel like this, which stretches three kilometres [about two miles] high, can travel halfway round the globe in a week.

Toepfer said the haze was the result of forest fires; the burning of agricultural wastes; dramatic increases in the burning of fossil fuels in vehicles, industries and power stations; and emissions from millions of inefficient cookers. He said the UN's preliminary report on what it dubbed the "Asian Brown Cloud" was a timely reminder to the coming Earth Summit in Johannesburg, South Africa, (August 26- September 4) that action, not words, was vital to the future of the planet.

"The huge pollution problem emerging in Asia encapsulates the threats and challenges that the summit needs to urgently address," he said. "We have the initial findings and the technological and financial resources available. Let's now develop the science and find the political and moral will to achieve this for the sake of Asia, for the sake of the world," he added.

Scientists say it's too early to draw definite conclusions about the impact of the haze, and of similar hazes over East Asia, South America and Africa. "We need much more basic scientific data to be able to establish what the consequences are for human health and the environment," said co-author Paul Crutzen, co-winner of the 1995 Nobel chemistry prize for his work on the ozone layer. But they warn the impact could be global.

For many years, scientists believed only lighter "greenhouse gases" - such as carbon dioxide that is produced from burning fossil fuels such as gasoline and oil - were global in reach and effect. They now say microscopic, suspended particles of pollutants - generically called aerosols by atmospheric scientists - also travel the globe.

It's unclear what the haze's relationship is to global warming, which many scientists believe is fuelled by the man-made emission of greenhouse gases that trap the Earth's heat.

The haze appears to block sunlight, creating some cooling effect on the ground, but its heat-absorbing properties are thought to be warming the lower parts of the atmosphere considerably. The combination of surface cooling and lower atmosphere heating could be altering the winter monsoon, sharply reducing rainfall over northwestern Asia and increasing it along the eastern coast.

Toepfer said scientists and policy-makers "should avoid making premature final assessments", but should start trying to cut pollution by introducing more efficient heating stoves in developing countries and turning to solar power and other clean sources of energy.

Professor Victor Ramanathan, one of the more than 200 scientists involved in the study, said the haze was cutting the amount of solar energy hitting Earth's surface beneath it by up to 15 percent.

"We had expected a drop in sunlight hitting the earth and sea, but not one of this magnitude," he said.

The report calculated that the haze - 80 percent of which was man-made - could cut rainfall over northwest Pakistan, Afghanistan, western China and western central Asia by up to 40 percent.

Apart from drastically altering rainfall patterns, the haze was also making the rain acid, damaging crops and trees, and threatening hundreds of thousands of people with respiratory disease.

Crutzen said atmospheric pollution could be contributing to up to 2 million premature deaths a year in India alone. "If present trends as they are continue, then we have a very serious problem," he said.

The report called for special monitoring stations to be set up to watch the behaviour of the cloud, and its impact on people and the environment.

"The concern is that the regional and global impacts of the haze are set to intensify over the next 30 years as the population of the Asian region rises to an estimated 5 billion people," the report said.

Ramanathan, a scientist at the Scripps Institution of Oceanography in La Jolla, Calif., said the surprises found by the study will drive researchers to keep studying human impact on the environment.

"We've been looking at environmental issues for the past several decades, yet the Asian haze came as a major surprise to us," he said. "We don't know how many more surprises we will find."
(The report is online at www.rrcap.unep.org/abc/impactstudy.)

How the pall will affect Lanka
By Kumudini Hettiarachchi
The dangerous 'molotov' cock tail of ash, acids, aerosols and other particles, dubbed the "Asian Brown Cloud" may have an impact on Sri Lanka's climate, weather patterns, agriculture, crops and people, says an air quality expert.

As the alert on the three-kilometre thick blanket was sent out by the United Nations Environment Programme, Dr. Suren Batagoda told The Sunday Times that the cloud was observed about three years ago when UNEP commissioned a study on global warming and climate change with strong emphasis on cloud formation.

Dr. Batagoda of the Air Resource Management Centre of the Environment Ministry said the country is studying the 'Brown Cloud' formation.

"As mentioned in the reports put out so far, the blanket of pollution is reducing the amount of sunlight or solar energy hitting the earth. This can affect the growth of crops as the photosynthesis process or the ability of plants to make their own food gets hindered without sunlight.

"On the other hand the 'Brown Cloud' will also absorb the heat which is reflected back into the atmosphere by the earth, warming the lower parts of the atmosphere. This could have effects on the climate such as rainfall patterns and timing of the monsoons, and also cause respiratory problems for people. In this situation, the microclimate, the climate within the immediate proximity of our country, can be affected as against the global climate."

The brown haze is the result of forest fires, the burning of agricultural wastes, dramatic increases in the burning of fossil fuels in vehicles, industries and power stations and emissions from millions of inefficient cookers burning wood, cow dung and other 'bio fuels', according to the UN report.

How has Sri Lanka contributed to air pollution? The answer was very simple - mainly through vehicle emissions and industrial emissions as a result of burning fuel. A major pollutant, sulphur dioxide, comes from thermal power plants dotting Colombo.

The Air Resource Management Centre, along with other relevant institutions, has been implementing a plan of action to curb the country's activities in polluting the atmosphere. "This is specifically not with regard to the Brown Cloud but in general," explained Dr. Batagoda.

Three major steps have been taken in Sri Lanka's bid to become more responsible in its fight against air pollution.

"The first came into effect in June this year, when a ban was introduced on leaded petrol. The second will be in force by January next year when all vehicles will have to undergo tests for their emissions and get certificates to be on the road. The Ministry of Environment has already gazetted vehicle emission standards, fuel quality standards and vehicle importation standards. One hundred vehicle testing centres, accredited to the Department for the Registration of Motor Vehicles will be set up to test emissions," he said.

No link-ups have been made yet among countries in the region to fight the Brown Cloud, but air pollution has been the focus of the South Asian Environmental Ministers' Conference and the South Asian Co-operative Environment Programme, said Dr. Batagoda.

"Plans are also underway to set up weather observation stations under the Male Declaration to study the transboundary movement of air pollution. Sri Lanka may soon have such stations in Pidurutalagala, Horton Plains or Anuradhapura."

The Brown Cloud cannot be blamed on any one of the countries. It's a collection of emissions from different countries. When there is a concentration of sulphur and other secondary particles in the atmosphere, a photochemical smog, which is reddish brown, is formed. This contains a high content of noxious gases, explains Priyantha Samarakkody of the Air Quality Monitoring Programme of the NBRO.

If it comes down with rain water, it could affect human life, vegetation, forest cover and materials such as rubber and plastic.

"The biodiversity, Asian countries are famous for could face problems. Sensitive species may die out. In people, there is the possibility of skin cancer, asthma and eye irritations. An adult inhales 13 cubic metres of air per day. Children breathe more air per their body weight. Their respiratory systems are developing," he said.

Countries need to be more accountable.

The damage from the Brown Cloud could be wide ranging but also within nature there is a natural scavenging system, such as rain and wind, which could dilute the effects of the cloud," he says.

Adding fireworks to the fire
Did you know that the lovely fireworks we all enjoyed on the opening day of the Asian Games would have spewed out more sulphur dioxide into the environment, adding to the pollution?

This is the question that Hemantha Withanage of the Environmental Foundation has in the backdrop of warnings against the Asian Brown Cloud.

The vividly-hued firecrackers costing millions of rupees were given free by China.
"The colours come from chemicals such as sulphur, potassium and heavy metals like magnesium, which are harmful to people's health.

The sulphur rises and gets into the clouds and is instrumental in creating acid rain," Mr. Withanage said.

'We will be affected but …
As the Brown Cloud is not directly over Sri Lanka, but over the ocean to the northwest of the country, we will not be as badly affected as India, Pakistan and Afghanistan, assures Dr. W.L. Sumathipala of the Montreal Unit of the Ministry of Environment.

However, the cloud is in a high pressure area. So it is in a doldrum state, with a low dispersion capacity. Therefore, our weather patterns will change.

"This is the monsoon period and in the past few weeks, we have hardly had any rain. This may be due to the Brown Cloud, among other regional factors," he said. Low solar radiation will hinder water evaporation, which in turn will lead to low rainfall and more drought conditions. Crops and forest cover would be affected.

With regard to the effect of the Brown Cloud on men, women and children, he said when the atmosphere is polluted it is bound to have an adverse impact on health. Usually, heavy rains purify the environment, but fewer showers will cause more disease. Ash and other pollutants will also have their effect on the people.


Back to Top
 Back to Index  

Copyright © 2001 Wijeya Newspapers Ltd. All rights reserved.
Webmaster