Feature on Climate Change : July, 2005

Environmental Articles Archive: Climate Change
Web version prepared by BCAS
September, 2006

International Ozone Day
Ozone layer depletion threat to ecosystem
Khandoker Azizul Islam

Over the past three decades, anthropogenic emissions of chemical compounds into the atmosphere have caused pollution in environment with serious impact on human health. Chemicals like chlorofluorocarbons (CFCs) are produced deliberately and end up in the atmosphere by accident from different sources. Sulfur dioxide (SO2) and carbon monoxide (CO) are unavoidable by-products of burning fossil fuels. Air pollution, acid rain, contamination by toxic chemicals, depletion of the stratospheric ozone layer and changes in the global atmosphere system are all major environmental threats to ecosystems and human beings.

Ozone (O3) gas is an unstable form of oxygen (O2) and is created by natural processes such as ultraviolet radiation in the upper atmosphere and by lightning. Ozone plays a key role in the atmosphere.

The ozone layer absorbs a portion of the radiation from the sun, preventing it from reaching the planet's surface. It absorbs the portion of ultraviolet light called UVB. UVB has been linked to many harmful effects, including various types of skin cancer, cataracts, and harm to some crops, certain materials, and some forms of marine life.

Ozone molecules are constantly formed at any given time and destroyed in the stratosphere. The total amount remains relatively stable. While ozone concentrations vary naturally with sunspots, the seasons, and latitude, these processes are well understood and predictable. Each natural reduction in ozone levels has been followed by a recovery. Scientific evidence has shown that the ozone shield is being depleted well beyond changes due to natural processes.

The ozone layer acts like a giant sunshade. It protects plants and animals from much of the sun's harmful ultraviolet radiation. It shields plants and animal life from UVB, which, in high doses of incidence, can be particularly damaging to environment and natural life. The absorption of UVB by the ozone layer also creates a source of heat, which plays a key role in the temperature structure of the atmosphere.

Ozone layer depletion is a threat to humanity and all living organisms. Ozone layer depletion seems likely to increase the rate of greenhouse warming, by reducing the effectiveness of the carbon dioxide sink in the oceans. Phytoplankton (micro-organisms) in the oceans assimilates large amounts of atmospheric carbon dioxide. Increased UV radiation reduces phytoplankton activity significantly. This means that large amounts of carbon dioxide remain in the atmosphere.

Increasing amounts of UV radiation have an impact on plankton and other tiny organisms at the base of the marine food web. These organisms provide the original food source for all other living organisms in the oceans. A high increase in UV radiation may disrupt many ecosystems on land. Rice production may be drastically reduced by the effects of UVB on the nitrogen assimilating activities of micro-organisms. With a diminishing ozone layer, it is likely that the supply of natural nitrogen to ecosystems, such as tropical rice paddies, will be significantly reduced.

Most plants (and trees) grow more slowly and become smaller and stunted when exposed to large amounts of UVB. Increased UVB also inhibits pollen germination.

The protection of the earth's ozone layer is one of the major challenges over the past 30 years, spanning the fields of environment, trade, international cooperation and sustainable development. The thinning of the ozone layer threatens human health through diseases such as skin cancer, eye cataracts and immune deficiency, affects flora and fauna, and also influences the planet's climate. Ozone depletion is brought about by a number of chemicals known as ozone depleting substances (ODS), the most notorious of which are the chlorofluorocarbons (CFCs).

CFCs, created by humans, are a main cause of the hole in the ozone layer, which permits ultraviolet (UV) radiation to hit the earth surface. This radiation can also damage plant and marine life. Scientists believe that the development of ozone layer hundreds of million years ago allowed the evolution of complex life forms on earth.

Worldwide, CFCs are declining because of the control on their use under the Montreal Protocol, especially among the countries with the heaviest use from 1986 to 1998. Cape Grimm Global Atmosphere Watch Monitoring Station located in Australia measures worldwide CFCs on the troposphere, the lowest layer of the atmosphere, which extends to the ground about 6 miles above sea level.

International cooperation has been the key to protecting the stratospheric ozone layer. Nations agreed in principle to tackle a global problem before its effects became evident or its existence scientifically proven.

In 1977, the United States banned use of CFCs in non-essential aerosols. Canada, Norway and Sweden enacted similar control measures. The European Community (EC) froze production capacity and began to limit use of aerosols. These initiatives, though useful, provided only a temporary respite. After falling for several years, CFC consumption began increasing again in the 1980s, as non-aerosol uses, such as foam blowing, solvents and refrigeration, increased. Stricter control measures were needed and UNEP and several developed countries took the lead, calling for a global treaty on stratospheric ozone layer protection (Benedick 1998).

Due to continuous efforts by the international communities the global consumption of ODS has decreased markedly and the ozone layer is predicted to start recovering in the next one or two decades and to return to a pre-1980 level by the middle of the 21st century of all the future control measures of the Montreal Protocol are adhered to by all countries (UNEP 2000a).

India and China are the largest regional producers and users of CFCs. China's consumption of ODS increased more than 12 percent per year during 1986-94. India is the second largest producer and the fourth largest consumer of CFCs in the world (UNEP 1998). The Multilateral Fund of the Montreal Protocol and GEF have been helping the region meet the goals of the Montreal Protocol. China has made a commitment to phase out the consumption of ODS by 2010. It has already banned the establishment of new CFC- and halon-related production facilities, and developed general and sector-specific plans with the help of the World Bank and the Multilateral Fund. The latter has approved a World Bank project which will help India phase out CFC production by 2010.

Bangladesh accessed the protocol on August 2, 1990. Until August 19, 2004 Montreal Protocol was ratified by 187 countries. Through ratification/ accession to the protocol, government is committed to protecting the ozone layer by phasing out the use of ozone-depleting substances within fixed period of time. As per Montreal Protocol maximum allowable limit of use of ODS for Bangladesh is 580.4 MT (Metric Tons) up to December 2004, 290.2 MT up to December 2007, 087.1 MT up to December 2009 and 000.0 MT for January 2010.

In 1994, the United Nations General Assembly voted to designate September 16 as "World Ozone Day", to commemorate the signing of the Montreal Protocol on that date in 1987.

Bangladesh is going to observe the International Ozone Day on 16 September along with other countries of the world. Through observance of the International Ozone Day it would be possible to create awareness among people to protect the ozone layer and this will ensure sustainable and livable environment for all .

The writer is a senior assistant secretary of the Ministry of Environment and Forest and is a reelance contributor to The Daily Star.

Source: The Daily Star, September 16, 2006

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International Ozone Day
Ozone layer depletion threat to health and environment
Muhammed Shahidul Islam

The International Ozone Day observed in the country as elsewhere of the world on 16 September as part of the global effort to create mass awareness about the ozone layer depletion and its consequences on the earth.

Bangladesh has been observing the day since 1995 along with other member countries of the United Nations. The decision to observe September 16 every year as the international Ozone Day was adopted at UN on December 19, 1994.

The ozone layer is a concentration of ozone molecules in the stratosphere - the layer of earth's atmosphere between about 10 and 60 kilometres above the earth surface. About 90 per cent of the planet's ozone is within the ozone layer. The layer of the earth's atmosphere that surrounds us is called the troposphere. Actually, a layer of atmosphere that extends from about 6 to 10 kilometres upwards from the earth's surface is called troposphere. Stratospheric ozone is a naturally-occurring gas that filters the sun's ultraviolet (UV) radiation. A diminished ozone layer allows more radiation to reach the Earth's surface.

Anthropogenic emissions of chemical compounds into atmosphere have caused environment pollution with serious impact on human health over the past 30 years. Chemicals like chlorofluorocarbons (CFCs) are produced that end up in atmosphere from different sources. Sulfur dioxide (SO2) and carbon monoxide (CO) are unavoidable by-products of burning fuels. Air pollution, acid rain, contamination by toxic chemicals, depletion of the stratospheric ozone and changes in the global atmosphere system are all major environmental threats to ecosystem and human beings.

Ozone (O3) gas is an unstable form of oxygen (O2) and is created by natural processes such as ultraviolet radiation in the upper atmosphere and by lightning. Ozone plays a key role in the atmosphere.

The ozone layer absorbs a portion of the rediation from the sun, preventing it from reaching the planet's surface. It absorbs the portion of ultraviolet light called UVB. UVB has been linked to many harmful effects, including various types of skin cancer, cataracts, and harm to some crops, certain materials, and some forms of marine life.

0zone molecules are constantly formed at any given time and destroyed in the stratosphere. The total amount remains relatively stable. While ozone concentrations vary naturally with sunspots, the seasons, and latitude, these processes are well understood and predictable. Each natural reduction in ozone levels has been followed by a recovery. Scientific evidence has shown that the ozone shield is being depleted well beyond changes due to natural processes.

The ozone layer acts like a giant sunshade. It protects plants and animals from much of the sun's harmful ultraviolet radiation. It shields plants and animal life from UVP, which, in high doses of incidence, can be particularly damaging to environment and natural life. The absorption of UVB by the ozone layer also creates a source of heat, which plays a key role in the temperature structure of the atmosphere.

Most plants (and trees) grow more slowly and become smaller and stunted when exposed to large amounts of UVB. Increased UVB also inhibits pollen germination. Pollen, usually a type of yellow powder formed in flowers and when carried by the wind and insects, can fertilise other flowers.

CFCs, which are chemicals created by humans, are a main cause of the hole in the ozone layer, which permits ultraviolet (UV) radiation to hit the earth surface. UV radiation causes skin cancer in humans.

This radiation can also damage plant and marine life. Scientists believe that the development of ozone layer hundreds of million years ago allowed the evolution of complex life forms on earth.

Research has shown that even small amounts of UV-B radiation can cause considerable harm. UV-B damages the genetic material of DNA and is related to some types of skin cancer. UV-B radiation can not only cause cancer but also impair the body's ability to fight it off. It suppresses the immune system making it easier for tumors to take hold and spread. The same process also makes the people vulnerable to infectious diseases, such as herpes, that can enter the body through the skin. Long-term exposure to UV-B is also associated with the risk of damage to the eye.

UV-B radiation can penetrate up to 20 meters down in clear water. There is strong evidence to suggest that exposure to UV-B is harmful to small creatures such as plankton, the larvae of fish, shrimp and crab, and to plants essential to the marine food chain. Living mostly near the poles and, therefore, particularly exposed to the impact of ozone depletion, phytoplanktons could suffer a loss of 5 per cent in number as a result of a 16 per cent level of ozone depletion, which translates into a loss of 7 million tones offish per year.

Plant-growth may be directly hampered by UV-B radiation harming yields and quality of crops and also damaging forests.

Depletion of the stratospheric ozone and consequent increase in the incidence of UV-B radiation can have important effects on the troposphere, the lower region of the atmosphere. The chemical reactivity in troposphere will change increasing both production and destruction of ozone, which at this level is a harmful pollutant causing irritation to eyes and lungs.

Scientists have recognized the ozone hole as the first clear manifestation of global environmental change. One of the most important issues is the interrelation between the CFCs, which destroy the ozone, and greenhouse gases (GHGs), which contribute to climate change. Depletion of the ozone layer in the stratosphere with consequent increase in the incidence of UV-B radiation can cause enhancement of the greenhouse effect though reducing the productivity of phytoplankton and plants. Reduction in the productivity of marine and terrestrial ecosystems could thus, reduce the uptake of CO2 contributing to global warming and changes in the climatic conditions.

In 1977, the United States, banned use of CFCs in nonessential aerosols. Canada, Norway and Sweden enacted similar control measures. The European Community (EC) froze production capacity and began to limit use of aerosols. These initiatives, though useful, provided only a temporary respite. After falling for several years, CFC consumption began increasing again in the 1980s, as non-aerosol uses, such as foam blowing, solvents and refrigeration, increased. Stricter control measures were needed and UNEP and several developed countries took the lead, calling for a global treaty on stratospheric ozone layer protection (Benedick 1998).

India and China are the largest regional producers and users of CFCs. China's consumption of ODS increased more than 12 per cent per year during 1986-94. India is the second largest producer and the fourth largest consumer of CFCs in the world (UNEP 1998). The Multilateral Fund of the Montreal Protocol and GEF has been helping the region meet the goals of the Montreal Protocol. China has made a commitment to phase out the consumption of ODS by 2010. It has already banned the establishment of new, CFC- and halon-related production facilities, developed general and sector-specific plans with the help of the World Bank and the Multilateral Fund. The latter has approved a World Bank project, which will help India phase out CFC production by 2010.

Bangladesh accessed to the Montreal Protocol on 2nd August 1990 and rectified its London, Copenhagen and Montreal Amendments in March 1994, November 2000 and July 2001 respectively.

Bangladesh is operating under Paragraph 1 of Article 5 of the Montreal Protocol. According to the Protocol, control measures have to be imposed on the import and consumption of CFCs from 1 July 1999. From that time consumption of CFCs should not exceed the average consumption of CFCs in 1995,1996 and 1997.

The Government of Bangladesh undertook a reconnaissance study on import and consumption of ODSs in 1993 and based on the study, a detailed Country Programme was drawn in 1994.

In pursuance of commitment to phase-out ODSs with in the stipulated period, National Technical Committee on ODS (NTCODS) was formed in 1994 headed by the secretary, Ministry of Environment and Forest and the Ozone Cell was constituted 1995 under Chairmanship of Director General, Department of environment.

Some projects were implemented and some activities were undertaken under the Montreal Protocol.
Surveys are being conducted on the ODS consumption patterns in Bangladesh every year since 1995. During this period the highest consumption of ODS was recorded in 1999 (946.80 MT) and the lowest

(509.29 MT) in 2005. In order to initiate ozone research activities and enhance observation capacities in terms of column measurements, profile measurements and ground UV measurements, DoE has jointly chalked-out a plan with Bangladesh Meteorological Department (BMD). As DoEs financial capacity is limited and technical knowledge is at a low level it's necessary and urgent that development partners, including UN agencies, come to enable us carry out ozone research activity and enhance observational capacities.

The ozone hole is a global problem. In this case, media can represent a powerful tool, able to pressurize the Government and policy makers to bring in programs to address this issue and to create awareness among the general people to contribute in solving the global problems, like Ozone Layer Depletion which will ensure sustainable and livable environment for all.

Source: Holiday, September 22, 2006

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A New Global Warming Strategy:
How Environmentalists are Overlooking Vegetarianism as the Most Effective Tool Against Climate Change in Our Lifetimes by Noam Mohr

Summary

Global warming poses one of the most serious threats to the global environment ever faced in human history. Yet by focusing entirely on carbon dioxide emissions, major environmental organizations have failed to account for published data showing that other gases are the main culprits behind the global warming we see today. As a result, they are neglecting what might be the most effective strategy for reducing global warming in our lifetimes: advocating a vegetarian diet.

Global Warming and Carbon Dioxide

The environmental community rightly recognizes global warming as one of the gravest threats to the planet. Global temperatures are already higher than they’ve ever been in at least the past millennium, and the increase is accelerating even faster than scientists had predicted. The expected consequences include coastal flooding, increases in extreme weather, spreading disease, and mass extinctions.

Unfortunately, the environmental community has focused its efforts almost exclusively on abating carbon dioxide (CO2) emissions. Domestic legislative efforts concentrate on raising fuel economy standards, capping CO2 emissions from power plants, and investing in alternative energy sources.

Recommendations to consumers also focus on CO2: buy fuel-efficient cars and appliances, and minimize their use. ,

This is a serious miscalculation. Data published by Dr. James Hansen and others show that CO2 emissions are not the main cause of observed atmospheric warming. Though this may sound like the work of global warming skeptics, it isn’t: Hansen is Director of NASA’s Goddard Institute for Space Studies who has been called “a grandfather of the global warming theory.” He is a longtime supporter of action against global warming, cited by Al Gore and often quoted by environmental organizations, who has argued against skeptics for subverting the scientific process. His results are generally accepted by global warming experts, including bigwigs like Dr. James McCarthy, co-chair of the International Panel on Climate Change’s Working Group II.

The focus solely on CO2 is fueled in part by misconceptions. It’s true that human activity produces vastly more CO2 than all other greenhouse gases put together. However, this does not mean it is responsible for most of the earth’s warming. Many other greenhouse gases trap heat far more powerfully than CO2, some of them tens of thousands of times more powerfully. When taking into account various gases’ global warming potential—defined as the amount of actual warming a gas will produce over the next one hundred years—it turns out that gases other than CO2 make up most of the global warming problem.

Even this overstates the effect of CO2, because the primary sources of these emissions—cars and power plants—also produce aerosols. Aerosols actually have a cooling effect on global temperatures, and the magnitude of this cooling approximately cancels out the warming effect of CO2. The surprising result is that sources of CO2 emissions are having roughly zero effect on global temperatures in the near-term!

This result is not widely known in the environmental community, due to a fear that polluting industries will use it to excuse their greenhouse gas emissions. For example, the Union of Concerned Scientists had the data reviewed by other climate experts, who affirmed Hansen’s conclusions. However, the organization also cited climate contrarians’ misuse of the data to argue against curbs in CO2. This contrarian spin cannot be justified.

While CO2 may have little influence in the near-term, reductions remains critical for containing climate change in the long run. Aerosols are short-lived, settling out of the air after a few months, while CO2 continues to heat the atmosphere for decades to centuries. Moreover, we cannot assume that aerosol emissions will keep pace with increases in CO2 emissions. If we fail start dealing with CO2 today, it will be too late down the road when the emissions catch up with us.

Nevertheless, the fact remains that sources of non-CO2 greenhouse gases are responsible for virtually all the global warming we’re seeing, and all the global warming we are going to see for the next fifty years. If we wish to curb global warming over the coming half century, we must look at strategies to address non-CO2 emissions. The strategy with the most impact is vegetarianism.

Methane and Vegetarianism

By far the most important non-CO2 greenhouse gas is methane, and the number one source of methane worldwide is animal agriculture.

Methane is responsible for nearly as much global warming as all other non-CO2 greenhouse gases put together. Methane is 21 times more powerful a greenhouse gas than CO2. While atmospheric concentrations of CO2 have risen by about 31% since pre-industrial times, methane concentrations have more than doubled. Whereas human sources of CO2 amount to just 3% of natural emissions, human sources produce one and a half times as much methane as all natural sources. In fact, the effect of our methane emissions may be compounded as methane-induced warming in turn stimulates microbial decay of organic matter in wetlands—the primary natural source of methane.

With methane emissions causing nearly half of the planet’s human-induced warming, methane reduction must be a priority. Methane is produced by a number of sources, including coal mining and landfills—but the number one source worldwide is animal agriculture. Animal agriculture produces more than 100 million tons of methane a year. And this source is on the rise: global meat consumption has increased fivefold in the past fifty years, and shows little sign of abating. About 85% of this methane is produced in the digestive processes of livestock, and while a single cow releases a relatively small amount of methane, the collective effect on the environment of the hundreds of millions of livestock animals worldwide is enormous. An additional 15% of animal agricultural methane emissions are released from the massive “lagoons” used to store untreated farm animal waste, and already a target of environmentalists’ for their role as the number one source of water pollution in the U.S.

The conclusion is simple: arguably the best way to reduce global warming in our lifetimes is to reduce or eliminate our consumption of animal products. Simply by going vegetarian (or, strictly speaking, vegan), , , we can eliminate one of the major sources of emissions of methane, the greenhouse gas responsible for almost half of the global warming impacting the planet today.

Advantages of Vegetarianism over CO2 Reduction

In addition to having the advantage of immediately reducing global warming, a shift away from methane-emitting food sources is much easier than cutting carbon dioxide.

First, there is no limit to reductions in this source of greenhouse gas that can be achieved through vegetarian diet. In principle, even 100% reduction could be achieved with little negative impact. In contrast, similar cuts in carbon dioxide are impossible without devastating effects on the economy. Even the most ambitious carbon dioxide reduction strategies fall short of cutting emissions by half.

Second, shifts in diet lower greenhouse gas emissions much more quickly than shifts away from the fossil fuel burning technologies that emit carbon dioxide. The turnover rate for most ruminant farm animals is one or two years, so that decreases in meat consumption would result in almost immediate drops in methane emissions. The turnover rate for cars and power plants, on the other hand, can be decades. Even if cheap, zero-emission fuel sources were available today, they would take many years to build and slowly replace the massive infrastructure our economy depends upon today.

Similarly, unlike carbon dioxide which can remain in the air for more than a century, methane cycles out of the atmosphere in just eight years, so that lower methane emissions quickly translate to cooling of the earth.

Third, efforts to cut carbon dioxide involve fighting powerful and wealthy business interests like the auto and oil industries. Environmental groups have been lobbying for years to make fuel-efficient SUVs available or phase out power plants that don’t meet modern environmental standards without success. At the same time, vegetarian foods are readily available, and cuts in agricultural methane emissions are achievable at every meal.

Also, polls show that concern about global warming is widespread, and environmental activists often feel helpless to do anything about it. Unless they happen to be buying a car or major appliance, most people wanting to make a difference are given little to do aside from writing their legislators and turning off their lights. Reducing or eliminating meat consumption is something concerned citizens can do every day to help the planet.

Finally, it is worth noting that reductions in this source of greenhouse gas have many beneficial side effects for the environment. Less methane results in less tropospheric ozone, a pollutant damaging to human health and agriculture. Moreover, the same factory farms responsible for these methane emissions also use up most of the country’s water supply, and denude most of its wilderness for rangeland and growing feed. Creating rangeland to feed western nations’ growing appetite for meat has been a major source of deforestation and desertification in third world countries. Factory farm waste lagoons are a leading source of water pollution in the U.S. Indeed, because of animal agriculture’s high demand for fossil fuels, the average American diet is far more CO2-polluting than a plant-based one.

Recommendations

Organizations should consider making advocating vegetarianism a major part of their global warming campaigns. At a minimum, environmental advocates should mention vegetarianism in any information about actions individuals can take to address global warming.

Government policy should encourage vegetarian diets. Possible mechanisms include an environmental tax on meat similar to one already recommended on gasoline, a shift in farm subsidies to encourage plant agriculture over animal agriculture, or an increased emphasis on vegetarian foods in government-run programs like the school lunch program or food stamps.

Source: Earth Save, September 30, 2006

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