Background Information
Sunil Malla
Degree Fellow
East West Center
Honolulu, Hawai'i, USA
and
Ph.D. Student
Economics Department
University of Hawai'i - Manoa
Honolulu, Hawai;i, USA
April 1999
Table of Contents
Section
Titles
Page
Acronyms
Executive Summary
i
ii
I
Background Information on Acid Rain
1
II
Review of Transboundary Air Pollution in Asia
6
III
Experiences from Europe and North America
16
IV
What can be done
18
References
21
EXECUTIVE SUMMARY
Scientists have discovered that air pollution from burning fossil fuels is the major
cause of acidic deposition, or acid rain as it is commonly known. The main chemicals
in air pollution that create acid rain are sulfur dioxide and oxides of nitrogen. Acid
rain emerged as a concern in the 1960s with observations of dying lakes and forest
damage in northern Europe, the United States, and Canada. It is now emerging as a
major problem in the developing world, especially in parts of Asia and the Pacific
region. Rapid urbanization with associated growth in industry and transportation
systems, has increased regional concerns with regard to acid rain. According to one
recent estimate, sulfur dioxide emission in Asia is expected to triple from 1990 levels
by 2010 if current trends continue.
The primary man-made source of emissions of oxides of sulfur and nitrogen in the
region are fossil fuel combustion in energy, industry, transport and
household/commercial sectors. The use of low quality fuels, inefficient methods of
energy production and consumption, the poor condition of vehicles and traffic
congestion are major causes of increasing emissions of acid rain. The impact of acid
rain is felt at the local, national, sub-regional and regional scales; via air quality
deterioration at the local level, and via the transboundary impacts of acid rain on
ecosystems at the national, sub-regional and regional levels. Such environmental
degradation can impose large costs on the economy and on society if proper
measures are not taken. It is estimated that the economic costs of environmental
degradation in Asia range from 1 to 9 per cent of a country’s total gross national
product (GNP).
There are several approaches to try to reduce acid rain, in particular, through
international influence, legislation and use of market forces. There are number of
technologies that can control acid rain before, during and after -combustion process.
Some preventive methods include: energy efficiency measures, fuel substitution and
public awareness. In summary, it is clear that improving the well-being of Asia does
not necessarily entail increased pollution of the environment. The key to future
development lies in providing the services which people need by using the most
efficient technologies, and consuming the lowest possible level of material
resources. These may be promoted using the most appropriate policy framework in
the region.
The main purpose of this report is to provide a background information on acid rain
and emissions reduction related issues in Asia for scientists, engineers, researchers
and general readers. Section I present a brief information on what is acid rain and
acidity, what causes acid rain and effects of acid rain. Section II reviews the present
status of acid rain in Asia. Section III summarizes European and North American
experiences of acid rain. Finally, Section IV looks into some of the major approaches
to reduce acid rain in Asia.
ACRONYMS
ADB
AIT
AFEs
ASEAN
EAP-AP
DEBITS
EWC
ESCAP
GEO
GMS
ICIMOD
LRTAP
MATCH
MISU
MRC
RAINS
SACEP
SERI
Sida
SEI
SMHI
SoE
UNEP
Asian Development Bank
Asian Institute of Technology
Acid Forming Emissions
Association of South-East Asian Nations
Environment Assessment Programme for Asia and the Pacific
East West Center
Economic and Social Commission for Asia and the Pacific
Global Environment Outlook
Greater Mekong Subregion
International Centre for Integrated Mountain Development
Long-range Transboundary Air Pollution
Mesoscale Atmospheric Transport Chemistry Model
Mekong River Commission
Regional Air Pollution Information and Simulation
South Asia Cooperative Environment Programme
Stockholm Environment Research Institute
Swedish International Development Co-operation Agency
Stockholm Environment Institute
Swedish Meteorological and Hydrology Institute
State of the Environment
United Nations Environment Programme
I. BACKGROUND INFORMATION ON ACID RAIN
1.1
INTRODUCTION
Since the beginning of time, humans have learned to make use of many things in nature such
as fire and electricity. From the early times through the Industrial Revolution to the Space
Age, humans have produced inventions that use many of the earth's varied energy resources
to make living easier. In many cases the energy comes from burning fossil fuels -- coal, oil
and natural gas. Some of the inventions that make our lives easier are also causing pollution.
Pollution is the release of harmful substances into the environment.
Scientists have discovered that air pollution from burning fossil fuels is the major cause of
acidic deposition, or acid rain as it is commonly known. The main chemicals in air pollution
that create acid rain are sulfur dioxide (SO2) and oxides of nitrogen (NOx). Acid rain usually
forms high in the clouds where SO2 and NOx react with water, oxygen and oxidants to form
various acidic compounds (such as sulfuric acid and nitric acid). These compounds then fall
to the earth as acid rain in either dry form (such as gas and particles) or wet form (such as
rainwater, snow and fog). Prevailing winds transport these compounds, sometimes hundreds
of kilometers, within the country and across the national borders. For example, more than 90
per cent of the acid rain affecting Norway originates in other countries (MoE-Norway, 1995).
While rapid economic development has created dynamism and wealth, Asia has at the same
time become dirtier, less ecologically diverse, and more environmentally vulnerable. The
prevailing government mentality of “Grow now and clean up later” and lack of institutional
capacity to implement its environmental policy in the region are two main reasons for Asia’s
environmental problems. Transbounary air pollution, in particular, the movement of acid
forming emissions (AFEs) is one of the emerging and serious issues in the region. Such
environmental degradation can impose large costs on the economy and on society if proper
measures are not taken. It is estimated that the acid rain related funding needed for the Asia
and the Pacific region will be roughly 2.3 billion US dollars for the year 2025 with an
average annual growth rate of 5.2 per cent (ADB, 1994).
1.2
WHAT IS ACIDITY
Acidic and basic are two extremes that describe chemicals, just like hot and cold are two
extremes that describe temperature. Mixing acids and bases can cancel out their extreme
effects, much like mixing hot and cold water can even out the water temperature. A substance
that is neither acidic nor basic is neutral. The potential of hydrogen ions (pH) scale measures
how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A
pH less than 7 is acidic. A pH greater than 7 is basic. Each whole pH value below 7 is ten
times more acidic than the next higher value. For example, pH 4 is ten times more acidic than
pH 5 and 100 times (10 times 10) more acidic than pH 6. The same holds true for Ph values
above 7, each of which is ten times more alkaline (another way to say basic) than the next
lower whole value. For example, pH 10 is ten times more alkaline than pH 9 and 100 times
(10 times 10) more alkaline than pH 8.
Pure water is neutral. But when chemicals are mixed with water, the mixture can become
either acidic or basic. Examples of acidic substances are vinegar and lemon juice. Laundry
detergents and ammonia are examples of basic substances. Chemicals that are very basic or
very acidic are reactive. These chemicals can cause severe burns. Automobile battery acid is
an acidic chemical that is reactive. Automobile batteries contain a stronger form of some of
the same acid that is in acid rain. Household drain cleaners often contain lye, a very alkaline
chemical that is reactive.
Fig.1: The pH Scale
1.3
Fig.2: pH Scale of Some Common Items
WHAT IS ACID RAIN
Acid rain is rain that is more acidic than normal. Acid rain is a complicated problem. Caused
by air pollution, acid rain's spread and damage involves weather, chemistry, soil, and the life
cycles of plants and animals on the land and from acid rain in the water.
Air Pollution Creates Acid Rain
Scientists have discovered that air pollution from the burning of fossil fuels is the major
cause of acid rain. Power plants and factories burn coal and oil. Power plants use that coal
and oil to produce the electricity we need to heat and light our homes and to run our electric
appliances. We also burn natural gas, coal, and oil to heat our homes. Cars, trucks, and
airplanes use gasoline, another fossil fuel.
The smoke and fumes from burning fossil fuels rise into the atmosphere and combine with
the moisture in the air to form acid rain. The main chemicals in air pollution that create acid
rain are sulfur dioxide and nitrogen oxides. Acid rain usually forms high in the clouds where
sulfur dioxide and nitrogen oxides react with water, oxygen, sulfuric acid and nitric acid.
Sunlight increases the rate of most of these reactions. Rainwater, snow, fog, and other forms
of precipitation containing those mild solutions of sulfuric and nitric acids fall to the earth as
acid rain.
Acid Precipitation
Water moves through every living plant and animal, streams, lakes, and oceans in the
hydrologic cycle. In that cycle, water evaporates from the land and sea into the atmosphere.
Water in the atmosphere then condenses to form clouds. Clouds release the water back to the
earth as rain, snow, or fog. When water droplets form and fall to the earth they pick up
particles and chemicals that float in the air. Even clean, unpolluted air has some particles
such as dust or pollen. Clean air also contains naturally occurring gases such as carbon
dioxide. The interaction between the water droplets and the carbon dioxide in the atmosphere
gives rain a pH of 5.6, making even clean rain slightly acidic. Other natural sources of acids
and bases in the atmosphere may lower or raise the pH of unpolluted rain. However, when
rain contains pollutants, especially sulfur dioxide and nitrogen oxides, the rain water can
become very acidic.
Dry Deposition
Acid rain does not account for all of the acidity that falls back to earth from pollutants. About
half the acidity in the atmosphere falls back to the earth through dry deposition as gases and
dry particles. The wind blows these acidic particles and gases onto buildings, cars, homes and
trees. In some instances, these gases and particles can eat away the things on which they
settle. Dry deposited gases and particles are sometimes washed from trees and other surfaces
by rainstorms. When that happens, the runoff water adds those acids to the acid rain, making
the combination more acidic than the falling rain alone. The combination of acid rain plus dry
deposited acid is called acid deposition.
Acid Rain is a Problem That Can Travel
The chemical reactions that change air pollution to acid rain can take from several hours to
several days. Years ago, when smokestacks were only a few stories high, pollution from
smokestacks usually stayed near the ground and settled on land nearby. This caused
unhealthy conditions for plants and animals near the smokestacks. To reduce this pollution,
the government passed a law permitting the construction of very tall smokestacks. At that
time, people thought that if the pollution were sent high into the air it would no longer be a
problem. Scientists now know that this is incorrect. Sending pollution high into the sky
increases the time that the pollution stays in the air. The longer the pollution is in the air, the
greater are the chances that the pollutants will form acid rain. In addition, the wind can carry
these pollutants for hundreds of miles before they become joined with water droplets to form
acid rain. For that reason, acid rain can also be a problem in areas far from the polluting
smokestacks. Dry deposition is usually more abundant near the cities and industrial areas
where the pollutants are released.
Natural Acids
There are also natural sources of acids such as volcanoes, natural geysers and hot springs.
Nature has developed ways of recycling these acids by absorbing and breaking them down.
Fig.3: Acid Rain Formation and Its Impact on Environment
These natural acids contribute to only a small portion of the acidic rainfall in the world today.
In small amounts, these acids actually help dissolve nutrients and minerals from the soil so
that trees and other plants can use them for food. The large amounts of acids produced by
human activities overload this natural acidity.
1.4
EFFECTS OF ACID RAIN
Acid rain causes acidification of lakes and streams and contributes to damage of trees. In
addition, acid rain accelerates the decay of building materials and paints, including
irreplaceable buildings, ancient monuments, statues and sculptures that are part of nation’s
cultural heritage. Also, prior to falling to the earth, SO2 and NOx gases and their particulate
matter derivatives, sulfates and nitrates, contribute to visibility degradation and impact public
health.
Surface Water
The effects of acid rain are most clearly seen in the aquatic or water environments (such as
lakes and marshes). Acid rain primarily affects sensitive bodies of water, i.e., those that rest
atop soil with a limited ability to neutralize acidic compounds (called “buffering capacity”).
In general, most lakes and streams have a pH value between 6 and 8. However, some lakes
are naturally acidic even without the effects of acid rain. Because of differences in emissions
and wind patterns, levels of acid deposition vary. This chart from the US - EPA's Acid Rain
Program homepage “http://www.epa.gov/docs/acidrain” shows that not all fish, shellfish, or
their food insects can tolerate the same amount of acid in the case United States.2 Frogs may
tolerate relatively high levels of acidity. At pH 5, most fish eggs can not hatch.
The US-EPA conducted a National Surface Water Survey (NSNW) to investigate the effects
of acidic deposition in over 1,000 lakes larger than 10 acres and thousands of miles of
streams of US and found that acid rain has been determined to cause acidity in 75 per cent of
the acidic lakes and about 50 per cent of the acidic streams indicating chemical conditions
unsuitable for the survival of sensitive fish species. It has been found that emissions from US
sources contributed to acidic deposition in eastern Canada, where 14,000 lakes are estimated
to be acidic (MoE-Norway, 1997).
The Ministry of Environment (MoE) - Norway recently reported that the critical loads for
acid rain in Norwegian river systems have been exceeded across about 36 percent of the
country. Since the 1970s, the number of lakes that have lost their fish stocks has more that
doubled, and is now estimated at roughly 4,000 to 5,000. In Norway, scientists now estimate
that an area of more than 110,000 km2 receive such large inputs of sulfur that the
environment
can
no
longer
withstand
acidification. If acidification caused by nitrogen is
included, the total area affected is about 120,000
km2.
Forest
Acid rain has been implicated in contributing to
forest degradation. There also is a concern about
the impact of acid rain on forest soils. There is
good reason to believe that long-term changes in
the chemistry of some sensitive soils may have
already occurred as a result of acid rain. As acid
rain moves through the soils, it can strip away
Fig.4: Lime being spread to combat
lake acidification in Sweden.
vital plant nutrients through chemical reactions, thus posing a potential threat to future forest
productivity.
Fig.5: Healthy forest growth in 1970 and
bleak landscape in 1986, Germany.
An extensive international monitoring programme involving 34 European countries reported
that despite reductions in air pollution in many countries, forest damage is found throughout
Europe, in particular, Central and Eastern Europe. A study by an international research
institute concluded that 75 percent of Europe’s forests are exposed to harmful levels of sulfur
deposition and estimated the cost of forest damage in Europe to be US $ 30.4 billion per year
(Worldwatch Institute, 1993).
Human and Health
SO2 interacts in the atmosphere to form sulfate
aerosols, which may be transported long distances
through air. Most sulfate aerosols are particles
that can be inhaled. According to recent studies,
higher levels of sulfate aerosols are associated
with increased morbidity (sickness) and mortality
from lung disorders, such as asthma and
bronchitis. The pollutants that cause acid rain also
reduce visibility limiting how far into the distance
we can see. The aerosols in the atmosphere,
reduce visibility by scattering light. Sulfate aerosols are the main cause of poor visibility.
Human-made Materials
Acid rain and the dry deposition of acidic particles are known to contribute to the corrosion
of metals and deterioration of stone and paint on buildings, ancient monuments, statues and
sculptures that are part of nation’s cultural heritage. The corrosion seriously depreciates the
objects value to society. Dry deposition of acidic compounds can also dirty buildings and
other structures, leading to increased maintenance costs.
Fig.7: The Ornamental figure made in
1702, Germany. It was intact 200
years later in 1908;however, 60
years later it had been irreparably
damaged by air pollution.
I. REVIEW OF TRANSBOUNDARY AIR POLLUTION IN ASIA
2.1
OVERVIEW
Although there has been major progress in controlling acid-forming emissions in some
countries, the global threat from acid rain is far from over yet. In fact, the dimensions of the
acid rain problem are growing rapidly in Asia, with SO2 emissions expected to as much as
triple from 1990 levels by 2010 if current trends continue. Curtailing the already substantial
acid rain damage in Asia and avoiding much heavier damages in the future will require
investments in pollution control on the order of those made in Europe and North America
over the past 20 years (R. Downing et al., 1997).
Even in developed countries where there have been serious efforts to control acid rain, the
story is more complicated than it once appeared. Questions remain in regards to how much
damage has been done to forests, lakes, and streams over the years; whether current progress
is sufficient to protect the most vulnerable ecosystems; and how soon acid-damaged areas
will recover.
Acid rain emerged as a concern in the 1960s with observations of dying lakes and forest
damage in northern Europe, the United States, and Canada. It was one of the first
environmental issues to demonstrate a large-scale regional scope, with the chief pollutants -oxides of sulfur and nitrogen from combustion of fossil fuels -- able to be carried hundreds of
miles by winds before being washed out of the atmosphere in rain, fog, and snow.
As evidence grew of the links between air pollution and environmental damage, legislation to
curb emissions was put in place. The 1979 Geneva Convention on Long-Range
Transboundary Air Pollution and its subsequent amendments set targets for reductions of
sulfur and nitrogen emissions in Europe that have largely been achieved. The 1970 and 1990
Clean Air Acts have led to similar improvements in the United States.
Scientific uncertainties about acid rain persist, however. In the case of forest damage, the
contribution of acid rain is hard to isolate from other stresses such as drought, fire, and pests
that figure heavily in forest health. In Canada, for example, losses to fires and insects exceed
the volume of timber harvested for industrial use (FAO, 1997). For this reason, the
contribution of air pollution to forest damage is a controversial subject, particularly in North
America. The most recent and authoritative assessment of forest conditions in Europe reports
that 25 percent of trees sampled in more than 30 countries were rated as damaged (having lost
more than 25 percent of their leaves). Damage has been increasing over the past 20 years and,
while the report notes the difficulty of identifying definitive causes, nearly one half of the
countries participating in the survey mentioned air pollution as a cause (EC-UN/ECE, 1996).
Acid rain is now emerging as a major problem in the developing world, especially in parts of
Asia and the Pacific region where energy use has surged and the use of sulfur-containing coal
and oil -- the primary sources of acid emissions -- is very high. An estimated 34 million
metric tons of SO2 were emitted in the Asia region in 1990, over 40 per cent more than in
North America (D. Downing et at. 1997 and WRI, 1996). Acid deposition levels were
particularly high in areas such as southeast China, northeast India, Thailand, and the Republic
of Korea, which are near or downwind from major urban and industrial centers. The effects
are already being felt in the agriculture sector. Researchers in India found that wheat growing
near a power plant where SO2 deposition was almost five times greater than the critical load
(the amount the soil can safely absorb without harm) suffered a 49 per cent reduction in yield
compared with wheat growing 22 kilometers away (T. Patel, 1997). In southwestern China, a
study in Guizhou and Sichuan provinces revealed that acid rain fell on some two thirds of the
agricultural lands, with 16 percent of the crop area sustaining some level of damage. Other
ecosystems are also beginning to suffer. A study of pines and oaks in acid rain-affected areas
of the Republic of Korea, both rural and urban, showed significant declines in growth rates
since 1970 (R. Downing et al., 1997).
Fig.8: Projected sulfur emissions in
developing country region.
Economic expansion and continued reliance on coal as a primary fuel is likely to increase
acid rain in Asia in the next two decades. By 2000, SO2 emissions in Asia will be greater than
those of North America and Europe combined, according to recent World Bank projections,
and emissions will continue growing rapidly, unless there are substantial investments in
pollution control equipment. By 2020, Asian SO2 emissions could reach 110 million metric
tons if no action is taken beyond current levels of control (R. Downing et al., 1997).
As a result, damage to natural ecosystems and crops is likely to increase dramatically. Large
regions of southern and eastern China, northern and central Thailand, and much of the
Korean peninsula could experience damaging sulfur deposition levels. In some industrialized
areas of China, for example, acid deposition levels may some day exceed those experienced
in Central Europe's "Black Triangle," a large swath of Poland, the Czech Republic, and
southeast Germany where both acid rain levels and forest damage were acute in the 1980s (R.
Downing et al., 1997).
Damage could be largely avoided if modern pollution control technologies, such as flue-gas
scrubbers, are widely adopted and if low-sulfur fuel is substituted where possible. In fact, the
World Bank calculates that use of the best available pollution control technologies could cut
acid deposition levels in half from 1990 levels by 2020 in Asia, even though energy use is
projected to triple during this period. But the price for this level of environmental protection
is steep: roughly US$90 billion per year throughout the Asia region, or about 0.6 percent of
the region's gross domestic product (R. Downing et al., 1997).
Less ambitious and lower-cost strategies can also cut acid-forming emissions substantially,
but the amount of environmental protection these strategies buy is commensurately less and
will not protect many areas from serious acid deposition. In the end, perhaps the most costeffective option for controlling acid rain will be to adopt energy-efficiency measures that cut
overall energy use and thus reduce emissions. If systematically employed, such energysaving measures could cut control costs from one quarter to one third, according to the World
Bank's analysis; in addition, these measures would yield ancillary benefits such as better air
quality and lower greenhouse gas emissions (R. Downing et al., 1997).
2.2
MORE TO DO IN THE DEVELOPED WORLD
In industrialized countries, environmental regulations restricting sulfur emissions and market
forces that favor greater use of natural gas -- which contains little sulfur - have proved
relatively effective in cutting SO2 emissions. However, even this success may not be enough
in some sensitive areas. A recent Canadian report concluded that SO2 emissions might have
to fall another three quarters if ecosystems in a large area of southeastern Canada were to be
adequately protected (D. Spurgeon, 1997). In addition, declines in SO2 emissions are likely to
be partially offset in the future by emissions of NOx, which have remained broadly constant
in the OECD countries since 1980. (See NOx Levels Are Still a Problem in Europe and North
America.) In much of Europe, NOx emissions are now creeping up again, due mainly to
increased vehicle numbers and usage (CEC, 1996).
Overall, however, acid-forming emissions (AFEs) have been largely de-coupled from
economic growth, and transboundary pollution has fallen substantially in the past 25 years,
resulting in less acid rain. It has therefore been somewhat of a mystery why damaged trees,
streams, and lakes have not bounced back in those areas where acid rain has diminished.
One possibility is that damage to ecosystems from acid deposition may be more fundamental
and long-lasting than was first believed. For example, scientists now report that acid rain
leaches as much as 50 percent of the calcium and magnesium from forest soils; these are
crucial minerals which buffer or neutralize acids and are essential for plant growth. If soil
chemistry is changed dramatically in this way, it may take many decades for all the linked
ecosystems to recover (J. Kaiser, 1996). A related problem is the continued leaching of heavy
metals and other substances that acid rain has mobilized in the soil, providing a persistent
source of toxicity to surrounding vegetation and aquatic life.
Tonnes S per 1 degree
No
1500 1000 5000 10000 25000 50000
Fig.9: Projected sulfur emissions in the world in 2025.
It is also becoming clear that the long-term impacts of acidification cannot be studied in
isolation from other environmental problems. Climate change and acidification have led to
decreases in dissolved organic carbon concentrations in North American lakes. Carbon
absorbs ultraviolet (UV) radiation, which has, in turn, increased due to depletion of the ozone
layer. In combination, these changes have resulted in much deeper penetration of UV
radiation into lake waters and higher death and disease rates among fish and aquatic plants
(J.W. Schindler et al., 1996). This effect can be compounded by drought when sulfur
compounds stored in lake sediments oxidize in response to falling water levels (N.D. Yan et
al., 1996). About 140,000 lakes in North America are estimated to have carbon levels low
enough to be at risk of deep UV penetration (R. Downing et al., 1997).
These data suggest that the problem of acid rain in developed countries does not end with
reduced emission. Although important progress has been made, forest recovery is likely to
take decades. Acidification of surface waters in some areas is likely to increase despite falling
deposition levels, as ozone depletion continues and the climate continues to warm.
2.3
RESEARCH STATUS IN ASIA
In Asia, where recognition of acid rain is already realized, very little research has been
conducted on modelling and monitoring. Limited monitoring data show that the acidity of
rainfall has been rising dramatically in some areas of the region. The degree to which this
increased acidity is affecting Asian ecosystems is unknown at present. However, from the
experience of North America and Europe, impacts in the region can be expected to be
significant.
In most Asian countries there does not seem to be either a strong scientific or a public
constituency to address the potentially serious problems in the future for long-range transport
and deposition of sulfur and nitrogen species, and for the consequent damage to ecosystems,
health and materials. In addition to their global implications, the long-term and regional/local
implications of these atmospheric emissions touch not only the natural environment, but also
have far-reaching implications for important commercial and cultural activities such as
forestry, agriculture, and tourism. In recent years, efforts have been made to understand this
phenomenon and possible mitigation options both at the national and regional levels.
2.4
OVERVIEW OF THE PROJECTS RELATED TO ACID RAIN IN ASIA
Recognition of acid rain problems resulting from the massive growth of fossil fuels use in the
region has its institutional genesis in 1989. In response to the above concern, an effort to
explore mechanisms to bring together a group of prominent scientists and policy makers from
around the globe to assess the magnitude of the problem and to recommend needed actions
began. Tables 1 and 2 present a brief summary of completed as well as on-going projects,
2025
2050
meetings/workshops on acid rain related issues in the region.
Table 1: Meetings/Workshops/Conferences Related to Acid Rain in Asia
Meetings/Workshops
1. First annual workshop
Support
US-DOE
4. First
Intergovernmental
meeting on the acid
deposition monitoring
network in East Asia
5. Policy dialogue on
regional air pollution
issue
EAJ
6. First Regional Seminar
on Acid Rain and
Emissions reduction in
Asia
7. First
National
Workshop on Acid
Rain in Asia Project
ADB,
UNEP
8. Second
National
Workshop on Acid
Rain in Asia Project
9. Second
Regional
Seminar on Acid Rain
and
Emissions
reduction in Asia
ADB,
UNEP
Objectives
Bringing experts from Asia, Europe &
North America to assess present &
future energy use, sulfur emissions, &
environmental risks from long range
transbounary air pollution.
Develop comprehensive program of
assessment & policy analysis which
identify effective strategies for dealing
with acid rain at both the national and
regional levels.
• Presentation of preliminary results for
the first emissions inventories, longrange transport calculations, &
ecosystem sensitivity classifications &
maps in Asia.
• Development of a detailed work plan
for the implementation of Phase I of a
project to be sponsored by ADB and
WB.
• Report on the Preparatory Activities
for
the
first
Intergovernmental
Meeting, and
• Implementation of preparatory phase
activities.
• Create broad dialogue of the air
pollution issues in Asia between policy
makers, NGOs and the scientific
community;
• Promote policy cycle in South Asia.
• Utilize
RAINS-ASIA
in
the
development of policies & programs to
reduce acid rain in Asia and to initiate
mitigation measures.
• Training on RAINS-ASIA model;
• Information on acid rain related issues
and upcoming project activities; and
• Discuss with participant on
transboundary transport of AFEs &
need for the regional cooperation to
address the problem.
• Discussions
with participants on
model feedback and its use.
ADB,
UNEP
•
•
Review RAINS-Asia model;
Review proposed national action
plans and programs to address
problems caused by AFEs on regional
basis.
24-25
1999
10. Acid Rain 2000
Japan
•
Sixth International Conference on
Acid Deposition
10-16 December
2000
(AIT, Bangkok, Thailand)
2. Second
workshop
annual
WB,
UNEP,
ESCAP
(AIT, Bangkok, Thailand)
3. Third
conference
annual
US-DOE,
ESCAP
(AIT, Bangkok, Thailand)
Sida, SEI
ADB,
UNEP
Period
November
1998
November
1990
November
1991
March 1998
March 1998
16-18
1998
March
July 1998
March 1999
May
Table 2: Projects Related to Acid Rain in Asia
Projects
1. Acid Rain and Emissions
Reduction
in
Asia
Project, Regional Phase I
Support
ADB
2. An
International
collaborative project on
acid rain and emissions
reduction in Asia
ADB, WB
3. Acid
Deposition
and
Monitoring Network in
East Asia
EAJ
4. RAINS-ASIA Phase II
WB
•
•
•
•
•
•
•
•
•
•
•
•
Sida
•
6. REG: Acid Rain and
Emissions Reduction in
Asia, Phase II
ADB
•
7. Potential For Use Of
Renewable Sources Of
Energy In Asia And Their
Cost Effectiveness In Air
Pollution Abatement
EU
•
8. Environment & Technical
Assistance In North-East
Asia Region.
9. Air Pollution Assessment
& Early Warning System
For Asian World Heritage
10. Sino-Norwegian
Cooperation Project On
Acid Rain
ESCAP,
ADB,
RMA
UNESCO
•
NORAD
•
5. Atmospheric
Environment
Developing
Program
Issues in
Countries
•
•
•
11. REG: Acid Rain and
Emissions Reduction in
Asia, Phase II
ADB
•
Objectives
Preparation of database;
SO2 concentration monitoring; and
National institution building, information
dissemination and outreach activities
Assist formulating national and regional
policies to address acid rain in Asia;
Develop basic strategies for the World Bank,
ADB, and donor institutions concerning policy
advice, institution buildings, and investment
initiatives in the borrowing countries; and
Strengthen Asian research capacity.
Create common understanding of state of acid
deposition problems in East Asia region;
Provide inputs for decision making aimed at
preventing adverse impact on human health
and environment due to acid deposition.
Increase awareness & train environment
experts on the RAINS-ASIA model;
Maintain and extend the work of the
international institutions that developed the
model, while further building Asian ownership;
Verify methodology and data before Phase III;
Provide opportunities to consult with Asian
countries/local institutes & obtain international
guidance to develop details of Phase III.
Enhance capacity of developing countries to
participate in programs and activities to resolve
atmospheric environmental problems and to
increase and facilitate the participation and
involvement of developing countries in
international initiatives and negotiations.
Expand & apply methodology developed in
Phase I to broader set of air pollution
applications in Asia on alternative energy &
abatement strategies.
Promotion of renewable forms of energy in
China and India by quantifying their potential
beneficial role in air pollution abatement
policies by an integrated assessment of the
costs and the environmental impacts of
renewable forms of energy, particularly in
comparison with other fossil fuels.
Built cooperation in Northeast Asian region.
Develop a system to better understand the
impact of air pollution on the World Heritage
(130 in Asia).
Capacity building for acid deposition research
in China (development of methodology,
training, research equipment improvement,
implementation assistance);
Development of the basis for a quality,
sustainable, long-term monitoring system;
Development of the basis for a sound,
science-based decision making.
Expand & apply the methodology developed in
Phase I to a broader set of air pollution
applications in Asia on alternative energy and
abatement strategies.
Period
1993 – 1995
1992 – 1994
1998 – 2000
1998 – 1999
March 1998
1997 – 1999
1996 – 1999
-
-
1999 – 2004
1997 – 1999
2.5
SOCIO-ENVIRONMENTAL INDICATORS & ENVIRONMENTAL STANDARDS
Table 3 summarizes socio-environmental indicators and environmental standards and
legalization in Asian countries. Ten of Asia’s 11 mega-cities exceed the WHO guidelines for
SO2 by a factor of at least three. The ambient level of SO2 is 50 per cent higher in Asia than
in either Africa or Latin America, although they are still one third of the level in industrial
countries.
The following are environmental regulations of selected Asian countries:
China: NEPA and its associated EPBs at the municipal and provincial levels are the leading
government bodies on environmental issues. While the country’s environmental regulations
are very stringent on paper, actual compliance by industry remains low due to lack of funds
and information on clean technologies. China’s environmental legislation related to air
pollution includes the (i) Basic Law on Environmental Protection (1979) and (ii) Law of Air
Pollution Prevention and Treatment (1995).
Japan: Japan has very strict environmental standards relating to industrial emissions and
levels of environmental compliance are among the highest in the world. Environmental
standards of major air pollutants are SO2, NOx, hydrocarbons, VOCs, dioxins and chlorinated
hydrocarbons. The leading government body issuing guidance to industry on environmental
issues is the MITI.
Republic of Korea: The Basic Environmental Policy Act has recently been amended to
require EIAs on developments on sites of 150 km2 or more. MoE is responsible for setting
environmental regulations while the MOTIE takes control of environmental issues affecting
industry. Korea hopes to impose the polluter pays principle by establishing a system of
permits and charges for water and air emissions. Enforcement of regulations was low until
the early 1990s. Now public awareness and health issues are driving the government to invest
and enforce. Also, Korean firms have been quick to take up the ISO 14001 issue, driven by
the fear that the standard will represent trade barriers into European markets where they are
expanding.
Taipei,China: The legislative system for environmental protection in Taiwan is now based on
four guiding principles: prevention of pollution; polluter pays; public participation; and
privatization of government functions. Almost 300 laws and regulations concerning
environmental protection have been established in Taiwan. The most significant were the
1987 Guidelines for Environmental Policy, which stated that the four principles above should
be included in all environmental law. A key piece of legislation was the EIA Act passed in
1994. This provides the foundation for environmental impact assessments in the future. The
EPA is in the process of drawing up a National Environmental Protection Plan, which will
present the country's recent progress and goals until the year 2011.
India: The first significant modern environmental law in India was the 1974 Water
prevention and Control of Pollution Act. This was followed by a similar one for air in 1981
and the 1986 Environment Protection Act. The later serves as umbrella legislation for the
protection and improvement of the environment. Of particular importance are the EIA
regulations of 1994, which make EIAs mandatory for 29 categories of industry and also
includes requirements for public hearings. Currently, there are over 200 pieces of
environmental legislation in India. The MoEF is the main authority in the environmental
field. Its executive arm is the Central Pollution Control Board (CPCB) which has local
"PCBs" around India. It has the legislation and bureaucracy to enforce, but until recently, the
penalties for non-compliance have been lower than the costs of reducing pollution. There
remains a huge amount of work to do. Environmental enforcement in India is still very much
"command and control" with the emphasis on end-of-pipe solution.
Indonesia: Environmental legislation in Indonesia encourages self regulation and
enforcement is weak, even by Asian standards. Overall responsibility for environmental
matters is in the hands of the State Ministry for the Environment, while the role of designing
and implementing new legislation falls to BAPEDAL. Indonesia's key environmental
principles are set out in the cornerstone environmental statute - Act No.4 of 1982. Critics
point to the lack of legislation in some areas (there are few air quality standards) and the lack
of enforcement.
Malaysia: Aside from Singapore and Hong Kong, Malaysia is probably the most advanced
country in Southeast Asia in environmental management. The Environmental Quality Act
(EQA) was introduced in 1974. Since then there have been 18 sets of regulations to
implement and revise this. The DoE has an interest in almost all aspects of environmental
quality and works closely with the other to ensure their policy fits with national standards and
regulations. Recent amendments to the EQA (1974) passed by parliament in June 1996
consolidated power in the hands of the DoE and are expected to enhance enforcement and
grow the environmental industry.
Thailand: Thailand's environmental legislation is comprehensive on paper, covering all major
pollution sources and formulated with the assistance of international experts. Environmental
legislation was overhauled in 1992 and six new measures introduced relating to: wildlife;
public health; energy conservation; hazardous substances; environmental quality, and
factories. Since then the PCD has tried to introduce the "polluter pays" principle in an attempt
to fund improvements, especially in Bangkok. However, enforcement has been poor and has
been hampered by the spread of environmental authority between many government
departments, both central and local.
Philippines: Perhaps due to its recent cultural history (strong US influence, Catholic, English
speaking population), the Philippines has had Asia's strongest grass-roots environmental
movements, largely geared towards protecting the country's forests and indigenous people.
The government however, has almost completely ignored the environmental issue until
recently. Compared to Thailand, Malaysia and Indonesia, ISO 14001 awareness in the
country is at an early stage. There are however, well organized business/environment groups
who are committed to raising awareness on environmental issues for the common good of
development in the country. It is believed that the key barrier to environmental improvement
in the Philippines is poverty.
Singapore: Over the past few years Singapore has positioned itself as a "clean and green" city
of Asia and a regional hub for environmental technology and environmental management
expertise. Singapore has a well-developed legislative framework for environmental
protection, which is produced and administered by MoE. Although corporate Singapore has a
good compliance record, MoE is concerned that many organizations are merely reactive in
their response to legislation and lack forward planning.
Vietnam: NEA is responsible for developing legislation and standards, assessing EIAs,
enforcement and environmental monitoring. Vietnam has one key piece of environmental
protection legislation, the national Law on Environmental Protection (NLEP), which was
passed in December 1993, effective in 1994.
Sri Lanka: Due to wake of ethnic violence that has gripped the country since 1982,
environmental issues have not been high on the government's list of priorities. Prior to this, in
1980, the National Environment Act was passed, and with it the CEA was formed, as a policy
making body under the Ministry of Transport, Environment and Women's Affairs. An
amendment in 1988 also gave it enforcement powers.
Cambodia: The Cambodian Ministry of Environment was established in November 1995,
with the aid of international bodies such as the ADB. Laws covering natural resources are
now under consideration and will be formalized in the near future.
Laos: The Laotian People's Democratic Republic, although one of Asia's poorest countries, is
making some progress in developing an environmental capacity. Since 1993, the
environmental issue has been the responsibility of the STENO, which has drafted an
environmental action plan.
Myanmar: Within the government there is a NCEA, formed in 1990, which has provided
input into the 1996-2001 five years plan. A document entitled the Maynmar National
Environment Policy was drafted in 1994, largely geared towards sustaining the country's biodiversity and forestry resources. Urban environmental infrastructure is virtually non-existent
and this will present major problems in the future should foreign investment in the country
take off.
III. EXPERINCES FROM EUROPE AND NORTH-AMERICA ON ACID RAIN
3.1
REVIEW OF EXISTING MODELS
In recent years, integrated assessment models developed in Europe and North America have
been utilized for international negotiations on acid rain. The purpose of these models is to
provide negotiators, regulators or researchers with a full regional and/or global picture of the
problems associated with the entire causal process from energy systems and emissions
through to the ultimate impact on natural and man-made systems. However, most of these
models are either global (focussed primarily on broad patterns of deposition or concentration
of different pollutants) or regional (focussed primarily on Europe or North America). Asia
lacks similar models like these to explore the possible impacts of acidification and its
mitigation options in the region.
Several models exist which are basically of two common types: Lagrangian and Eulerian.
The structure and complexity of models reflect their application. For example, long-term
(monthly and annual) operational models require much simpler formulations than short-term
episodic models. The following are brief summary of some of the existing models associated
with acid rain issues used mostly in Europe and North America:
Global Scale Models:
MOGUNTIA Model: The global transport models that have been developed to simulate the
atmospheric distribution of pollutants have to balance the need of a complex chemical
scheme, an accurate representation of transport and deposition processes, and restrictions
imposed by computational considerations. An example of such a model is MOGUNTIA
model that focuses on detailed representation of the background chemistry and is usually on a
10 by 10 degrees grid (approximately 550 by 550 km) or a 5 by 5 degree grid.
Besides, estimation of sulfur deposition, this model is also one of the few models used to
estimate global NH3 deposition. The model also captures the main features of the deposition
fields when a comparison is made to observations. However, discrepancies between the
observations and the models cannot entirely be used to fine-tune the model due to the scale of
the modelling.
GCTM Model: This model calculates the total deposition of reactive nitrogen to marine and
terrestrial ecosystems using estimates of current and future emissions of NOx from fossil fuel
combustion. The model has a horizontal resolution of approximately 265 km and eleven
vertical layers. Natural nitrogen emissions included are biogenic soil emissions, biomass
burning, lightning and injection from the stratosphere.
STOCHEM Model: This is a global 3 - dimensional lagrangian chemistry model, which has
been applied to the formation of tropospheric ozone. It has been shown that without
simultaneous action on the global scale to control tropospheric ozone precursors,
concentrations tropospheric ozone will increase in future years, with the possibility of
changing the intensity of regional-scale photochemical episodes. In developing countries the
ozone concentrations increase between 1992 and 2015 according to this model.
IMAGE 2.0 Model: The IMAGE 2.0 model is a multi-disciplinary, integrated model designed
to simulate the dynamics of the global society-biosphere-climate system. The objectives of
the model are to investigate linkages and feedback in the system, and to evaluate
consequences of climate policies. Dynamic calculations, are performed to year 2100, with a
spatial scale ranging from gird (0.5 X 0.5 degree latitude-longitude) to world regional level,
depending on the sub-model.
The model consists of three fully linked sub-systems: Energy-Industry, Terrestrial
Environment, and Atmosphere-Ocean. The fully linked model has been tested against data
from 1970 to 1990, and after calibration can reproduce the following observed trends:
regional energy consumption and energy-related emissions, terrestrial flux of CO2 and
emissions of greenhouse gases, concentrations of greenhouse gases in the atmosphere, and
transformation of land cover. The model can also simulate long term zonal average surface
and vertical temperatures.
Regional Scale Models
MATCH Model: The MATCH model has been developed as a tool for air pollution
assessment studies on different scales. It has primarily been used as a basis for decision
making concerning environmental protection. MATCH is a Eulerian 3-dimentional “off-line”
model, which means that the physical atmospheric data are taken from some external source
and fed into the model at regular time intervals. The model includes horizontal and vertical
transport, vertical diffusion, dry deposition, wet scavenging and chemical transformations.
The model developed by SMHI has been applied to developing countries to carry out regional
modelling at 1 by 1 degree.
This model takes meteorological data from an external source and fed into the model at
regular time intervals. The weather data used in this model are derived from the ECMWF’s
global analysis.
REMAPE Model: The main objective of this model is to investigate the processes and the
phenomena which controls the chemical composition on the troposphere over Europe by
means of advanced and integrated modelling. It is a 3 – Dimensional Eulerian model with
variable resolution (about 0.1 to 50 km) in the horizontal and sufficient vertical resolution
covering Europe or parts of Europe. The final version of the model is currently under review.
RAINS Model: RAINS is developed as a tool for the integrated assessment of alternative
strategies to reduce acid deposition in Europe. The model has found prominent application as
a scientific support tool during the international negotiations on the new sulfur protocol to the
Convention of Long-range Transboundary Air Pollution. Recently, a protocol was signed by
33 countries committing themselves to (country-specific) emission reduction obligations as
calculated with the RAINS model.
For purpose of study in Asia, the model has been modified and further developed (version
RAINS 7.0) to be applicable to Asia, provided that appropriate databases are prepared. The
RAINS model describes the pathways of emissions and mechanisms of acidification in the
environment for SO2, which is a major acidifying component.
3.2 SELECTED INTERNATIONAL ENVIRONMENTAL AGREEMENTS
The international agreements are the principle means by which the world community
expresses and implements consensus on measures to protect and preserve the environment for
the benefit of the present and future generations in the context of sustainable development.
Access to these international conventions, agreements and other legal instruments is essential
for taking appropriate measures at national and regional levels to translate these accords into
action, as well as for participating effectively in the progressive development of Environment
Law. Facilitating such access as widely as possible in the region is necessary. Table 4
presents current International Environmental Agreements related to acid rain.
Table 4: Related International Environmental Agreements
Conventions/Protocols
Date
Opened
1979
Objective
Parties
23
1.
Convention on LRTAP
2.
Convention
Protocol)
(Sulfur
1985
To protect the human environment against air pollution and to
gradually reduce and prevent air pollution, including LRTAP.
To provide for a 30 % reduction in sulfur emissions or
transbounary fluxes by 1993.
3.
Convention on LRTAP (Nitrogen
Protocol)
1988
To provide for the control or reduction of nitrogen oxides and
their transboundary fluxes.
4.
Convention
Protocol)
(VOCs
1991
5.
Montreal Protocol on Substances that
Deplete the Ozone Layer
1987
To protect the ozone layer by taking precautionary measures to
control emissions of substances that depletes it.
136
6.
United
Nations
Framework
Convention on Climate Change
1992
To achieve stabilization of greenhouse gas concentrations in the
atmosphere at a low enough level to prevent dangerous
anthropogenic interference with the climate system.
64
7.
on
on
LRTAP
LRTAP
ASEAN
Cooperation
Transbounary Pollution
Plan
on
1994
8.
Seoul Declaration on Environmental
Ethics
1997
9.
Male’ Declaration
10.
New Sulfur Protocol to the UN/ECE
Convention on LRTAP
1998
To provide for the control and reduction of emissions of Volatile
Organic Compounds in order to reduce their transboundary fluxes
so as to protect human health and the environment from adverse
effects.
This Plan initially addresses the following three transboundary
programme areas: (i) atmospheric pollution; (ii) movement of
hazardous wastes; and (iii) shipborne pollution.
To establish an evolving framework of ideals, principles, and
guidelines to sustain life on earth.
Declaration on Control & Prevention of Air Pollution and its
Likely Transboundary Effects for South Asia.
The 1998 Major Review of Strategies and Policies for Air
Pollution. It contains an assessment of Parties' performance in
relation to various Protocols.
21
23
8
7
-
7
1998
28
3.3
STANDARDS AND REGULATIONS
Emissions regulatory frameworks vary from economy to economy, depending largely on
geographic location, climate, population density, and degree of industrialization. Emissions
regulations may be set at the regional, sub-regional, national, state or local levels, and may
therefore vary at various sites in an economy. Whereas the emphasis in this proposal is on
regional and sub-regional standards and guidelines, information on national and/or local
standards is included where appropriate.
A recent trend in many countries in the region has been the strengthening of governance
structures for environmental protection. A large number of environmental institutions have been
established in the public sector, including environmental ministries. Independent environment
agencies have also been created to assist the environment ministries. Legalization, regulatory
standards and environmental planning procedures related to public works, particularly EIA, are
the most commonly used instruments of environmental management at national level.
ii
IV.
WHAT CAN BE DONE
Acid rain emissions can be reduced in many ways. The following are main approaches to try to
reduce acid deposition over Asia:
•
International and Regional Influence
Reducing individual country's emissions alone will do little to improve the state of the
environment in Asia. Unlike Europe, there is no conventions or rotocols on Long-range
Transboundary Air Pollution in the region. One of the immediate possible actions needed in
the region is to initiate an agreement on sulfur and nitrogen protocols. Lessons could be
learned from the European experience and recent initiation of ASEAN cooperative plan on
Transboundary Air Pollution and Male’ Declaration on Control and Prevention of Air
Pollution and its Likely Transboundary Effects for South Asia.
Malé Declaration on Control and
Prevention of Air Pollution and Its
Likely Transboundary Effects for
South Asia
•
Legislation
In Asia, country-level environmental standards and rigid regulatory regimes are either
ineffectively designed or inadequately implemented. Country should introduce laws, rules, and
regulations to limit pollution. Pollution licenses should be issued to industrial enterprises to
ensure that emissions are gradually reduced.
•
Use of Market Forces
Environmental taxes can be introduced to make polluting products more expensive that
"environmentally-friendly" ones such as tax on mineral oil and coal.
Unlike emissions of gases that threaten to enhance the greenhouse effect, acid emissions can be
eliminated almost completely, although it is more difficult to remove NOx than SO2. Many
methods are available, some preventive and some remedial.
Energy efficiency measures (for instance improvements of industrial processes to reduce
energy requirements and better insulation of buildings) reduce both acid emissions and other
emissions that may be harmful (e.g., CO2, hazardous substances).
iii
Fuel Substitution Measures such as from coal to oil or from oil to gas or switching to
renewable sources of energy (for e.g., hydropower, wind, solar).
Pre-combustion technologies remove sulfur prior to combustion by coal or oil cleaning. Up
to 35 percent of sulfur content of coal and oil can be removed by chemical washing.
Sulfur and nitrogen can be removed during combustion of coal or oil by adding lime or other
chemicals that absorb SO2. Ammonia can also be added to reduce NOx emissions.
One commonly used method of removing sulfur is known as flue gas desulfurization (FGD).
Sulfur is removed after combustion of the coal or oil by means of various types of filters. A
disulfurization method using sea-water has been developed in Norway. This removes more
than 95 per cent of the sulfur.
Burner specially constructed to give off as little NOx as possible can reduce NOx emissions
up to 40 per cent.
Catalytic converters in car engines, wood stoves, oil burners convert NOx to harmless
nitrogen.
Fig.11: Photovoltaic (PV) production
costs versus cell efficiency.
iv
References
MoE-Norway, 1995, Acid Rain Issues, Ministry of Environment- Norway, Oslo.
Worldwatch Institute, 1993, opt. Cited in MoE - Norway, 1995.
ADB (1997), Emerging Asia: Changes and Challenges, Asian Development Bank (ADB),
Manila.
ADB (Asian Development Bank). 1994. Financing Environmentally Sound Development.
Manila.
Commission of the European Communities (CEC), Progress Report from the Commission on the
Implementation of the European Community Programme of Policy and Action in Relation to the
Environment and Sustainable Development (CEC, Brussels, 1996), p. 56.
Conditions in Europe: Results of the 1995 Survey (EC-UN/ECE, Brussels and Geneva, 1996),
European Commission and United Nations Economic Commission for Europe (EC-UN/ECE),
pp. 23, 42-43.
D.W. Schindler et al., "Consequences of Climate Warming and Lake Acidification for UV-B
Penetration in North American Boreal Lakes," Nature, Vol. 379 (1996), pp. 705- 708.
David Spurgeon, "Canada 'Still Has a Long Way to Go' in Effective Control of Acid Rain,"
Nature, Vol. 390 (1997), p. 6.
Food and Agriculture Organization of the United Nations (FAO), State of the World's Forests
1997 (FAO, Rome, 1997), p. 157.
Jocelyn Kaiser, "Acid Rain's Dirty Business: Stealing Minerals from Soil," Science, Vol. 272
(April 12, 1996), p. 198.
Norman D. Yan et al., "Increased UV-B Penetration in a Lake Owing to Drought-Induced
Acidification," Nature, Vol. 381 (1996), pp. 141-143.
R. Downing, R. Ramankutty, and J. Shah, RAINS-ASIA: An Assessment Model for Acid
Deposition in Asia (The World Bank, Washington, D.C., 1997), pp. 11, 48, 54; Table 3, p. 27.
Tara Pattel, "Rampant Urban Pollution Blights Asia's Crops," New Scientist (June 14, 1997), p.
11.
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v