All about ozone Essay Example

plants would be unable to grow due to the harmful effects of UV-B radiation. As a result, oxygen production would decrease and most surface-dwelling organisms would be destroyed. Higher rates of health problems among humans have also been linked to increased exposure to UV-B radiation.

Health Canada states that UV-B radiation is harmful to humans and animals, causing skin cancer, eye damage, and weakened immune systems. These effects have been observed in humans and are expected to impact other animals as well. Terrestrial plant life is particularly at risk from higher levels of UV-B radiation due to its ability to destroy chlorophyll in leaves, leading to stunted growth and decreased crop yields. This also negatively affects forest ecosystem health and annual increments. Additionally, increased UV-B radiation has the potential to disrupt the food chain by reducing phytoplankton populations in oceans. According to Clair (1996), ozone layer depletion is primarily caused by human activities and pollutants.

The ozone layer has been harmed by humanity through the release of synthetic molecules that contain chlorine and/or bromine into the atmosphere. These molecules, such as CFCs (chlorofluorocarbons), are commonly used in both industries and households. Although they remain stable at lower altitudes, they are transported to the stratosphere through global air currents, wind, and atmospheric mixing. Alongside CFCs, other substances like halons, carbon tetrachloride, and methyl chloroform also play a role in depleting the ozone.

Naturally occurring molecules in the stratosphere, like nitrous oxide, can deplete ozone (O3). However, there are also natural factors that impact ozone levels. These factors include the quasi-biennial oscillation of stratospheric winds, which occur every 2.3 years, and the 11-year sunspot

cycle. Nevertheless, observations indicate that global ozone levels should not decrease by more than one to two percent during the sunspot cycle (Environment Canada, 1996). In the stratosphere, these molecules come into contact with UV-C radiation that breaks down chlorine into chlorine atoms (Cl). Subsequently, the chlorine atoms react with ozone (O3), leading to a separation of oxygen atoms and the formation of chlorine oxide (ClO) and oxygen (O2).

The Chlorine oxide is broken down into Chlorine and a free oxygen atom, continuing the ozone destruction process. According to Environment Canada (1996), a single Chlorine atom (Cl) can destroy ten thousand ozone molecules. The identification of human-produced chemicals that contribute to ozone layer depletion has highlighted the extent of the threat. In response, an international agreement was reached to regulate harmful chemicals and establish a timetable for their elimination. The 1987 Montreal Protocol, along with subsequent amendments in London 1990 and Copenhagen 1992, enforced this timetable. The Montreal Protocol represents significant achievements in international cooperation and environmental protection.

The Protocol allowed for adjustments to the timetable based on improving scientific knowledge about ozone depletion, resulting in faster phase-outs. In 1989, representatives from eighty countries gathered in Helsinki, Finland for a meeting to assess new information. They reached a unanimous agreement known as the "Helsinki Declaration," which mandated that all nations join the Vienna convention for protecting the ozone layer and adhere to the Montreal Protocol. The declaration also required phasing out of CFCs by 2000, halons as soon as possible, development of environmentally acceptable alternative chemicals and technologies, and provision of accessible information to developing nations. By 1995, more than one hundred and

fifty countries had ratified the Montreal Protocol.

Environment Canada (1993) has implemented various measures to comply with the phase-out of ozone-depleting substances. The production of chlorofluorocarbons, carbon tetrachloride, and methyl chloroform had to be stopped by the end of 1995. In the United States, methyl bromide is scheduled for phase-out by 2001, while hydrochlorofluorocarbons will also be completely phased out by 2030. To raise awareness about UV hazards, Environment Canada introduced a daily UV index that provides information on a daily basis. Consistent monitoring and global awareness are crucial aspects of Canada's efforts to protect the ozone layer. Moreover, Environment Canada emphasizes five measures aimed at controlling these substances and implementing a phase-out plan in accordance with the Montreal Protocol; this plan has already achieved many of its goals.

The use of hydrofluorocarbon (HFC) systems, specifically HFC-134a, in air conditioning has become common in new vehicles manufactured in Canada. These HFCs and hydrochlorofluorocarbons (HCFCs) were introduced as alternatives to chlorofluorocarbons (CFCs), which have a higher ozone-depleting potential. In Canada, regulations for the recovery and recycling of ozone-depleting substances have been implemented in 9 out of the 10 provinces. Newfoundland and Yukon are currently developing their own regulations, while guidelines are being prepared in the Northwest Territories. The Sierra Club launched the Zer-O-Zone project at Winnipeg City Hall on August 10, 1995 to increase public awareness and gain support for Manitoba's Ozone Protection Regulation.

Canada has entered into agreements with China, Brazil, and Venezuela to share technology and information regarding substances that result in ozone depletion. Additionally, developed countries have established a Multilateral Fund through the Montreal Protocol to assist developing nations in

eliminating controlled substances (Environment Canada, 1996). Acid rain occurs when pollutants in the atmosphere cause precipitation to become acidic. This can happen through dry or wet deposition. Power plants, industries, and vehicles emit pollutants such as sulphur dioxide (SO2) and nitrogen oxides (NOx). In the atmosphere, SO2 converts to sulphuric acid while NOx transforms into nitric acid. These weak acids then descend upon Earth's surface as rain, hail, drizzle, freezing rain,snow or fog during wet deposition. Alternatively, they can be deposited as acid gas or dust through dry deposition.

Normal rain has a slight acidity, but acid rain can be significantly more acidic, reaching up to 100 times the acidity of normal rain (Watt, 1987). The burning of fossil fuels releases chemicals into the atmosphere that can create these acidic pollutants. These pollutants can then be carried long distances by prevailing winds and weather systems before being deposited. In eastern Canada, over 50% of acid rain is caused by emissions from the United States (U.S. Environmental Protection Agency, 1991). While there are natural sources of SO2 and NOx, human activities contribute to over 90% of these pollutant emissions in North America. In Canada specifically, the largest sources of SO2 are the smelting or refining processes involving sulfur-bearing metal ores and the burning of fossil fuels for energy.

NOx pollutants are produced from various sources. Transportation is responsible for 35% of total emissions, industrial processes/fuel combustion account for 23%, power generation contributes 12%, and the remaining 30% comes from other sources (River Road Environmental Technology Centre, 1991). Acid rain has a significant impact on Canada, particularly in eastern regions. Approximately 4 million km2 or

43% of Canada's total land area is highly sensitive to acid rain (Hughs, 1991). The limited ability of eastern Canada to neutralize acidic pollutants makes it more susceptible to the effects of acid deposition. This region is characterized by thin, coarsely textured soil (glacial till) and granite bedrock typical of the Canadian Shield, which lacks the buffering capacity found in the deeper organic soils of western Canada. Moreover, compared to other regions in Canada, eastern Canada receives the highest amount of acidic deposition.

Western Canada has a lower impact from acid rain compared to other regions due to reduced exposure to acidic pollutants and a less sensitive environment. However, specific areas in the Canadian Shield region, such as Manitoba, Saskatchewan, and Alberta, still experience more severe consequences from acidic deposition. Acid rain can negatively affect trees by reducing their growth rates and increasing death rates. In southeastern New Brunswick, white birch trees have suffered damage caused by acid fog and acidic cloud precipitation. Additionally, high levels of acidic deposition can cause lakes, rivers, and streams that are susceptible to acidification to become acidic. This acidity can result in metals leaching into the water system from nearby soils (Hughs, 1991).

High levels of acidity and metals like aluminum can significantly harm water bodies and their ability to support aquatic life, leading to a decline in species diversity. Lakes and streams in areas with high acidic deposition are regularly monitored to assess their acidification status. A report by Environment Canada in 1996 found that among the Canadian lakes under monitoring, 33% showed improvement, 11% continued experiencing acidification, while the rest remained unaffected in terms

of acidity. The provinces of New Brunswick, Nova Scotia, Prince Edward Island, and Newfoundland have over 80% of their lakes falling into moderate to high sensitivity classes regarding aquatic sensitivity.

AQUATIC SENSITIVITY, BY PROVINCE

Concerns arise with asbestos cement pipe as the cement it contains may release asbestos fibers into the water system. This is problematic because asbestos is carcinogenic and poses serious health risks. Research shows that respiratory problems can be caused by particulate matter such as sulphate and acidic aerosols entering the lungs. Additionally, recent studies have linked prolonged exposure to ambient acidic aerosols with decreased lung function, higher rates of cardio-respiratory mortality, and deterioration of building materials like cement, limestone, and sandstone.

The deterioration of historic structures in the Atlantic Province, including the Basilica in St. John's, is caused by acidic pollutants. To address this problem, a Canadian Acid Rain Control Program was implemented in 1985 through agreements between the federal government and the seven provinces east of Saskatchewan. These provinces agreed to reduce their combined SO2 emissions to 2.3 million tonnes per year by 1994, which they successfully achieved one year ahead of schedule. By 1994, eastern Canada had decreased its total SO2 emissions to 1.7 million tonnes, representing a significant 56% decrease from the levels recorded in 1980.

Furthermore, in 1991, Canada made an agreement with the United States to reduce both SO2 and NOx emissions. As part of this agreement, Canada committed to implementing a permanent national limit on SO2 at 3.2 million tonnes by the year 2000 and achieving an estimated reduction of approximately 10% in NOx emissions from stationary sources by that

same year (NB., NF., NS., Departments of Environment, 1991).

Canada started working on a national strategy in 1995 to deal with acidic deposition and acidifying emissions. The main goal of this strategy was to establish new deposition objectives beyond the year 2000, in order to protect acid-sensitive ecosystems, human health, air visibility in Canada, and meet international obligations. In 1997, federal and provincial/territorial Ministers of Energy and Environment planned to review this strategy (Ryan, 1996).

In Newfoundland and Labrador, environmental pollution primarily stems from municipal sewage, vehicle emissions, municipal solid waste, total carbon dioxide (CO2) emissions, and primary natural resource processing. Among these sources of pollution, municipal sewage poses a significant concern that affects all Atlantic provinces. Of particular worry is the discharge of untreated sewage into Halifax harbour on a daily basis at a volume of 150,000 m3 (Whelan, 1996).

The Atlantic provinces, excluding PEI, have a common issue of lacking waste treatment. Actions should be taken throughout these provinces. There is a similar situation in both the St. John's harbor and the Halifax harbor. Despite having a smaller population, St. John's also faces problems due to the narrows at the harbor entrance. This narrows impedes the tidal current, preventing complete removal of waste products from the harbour. Even though the rural areas of Newfoundland are smaller, they still lack waste treatment facilities. Contamination of sediments with organic matter, heavy metals, and chemicals like PAHs and PCBs is a concern in these areas (Whelan, 1996). It is recommended to establish primary treatment plants in major population centers across Newfoundland and explore the possibility of secondary treatment as well.

In order

to continue disposing of waste in the Atlantic, it is recommended that small rural communities in Newfoundland conduct an environmental study to assess the area's capacity for decomposing waste. Additionally, there is a need for sewage treatment plants in these areas to accommodate population growth. This measure should have been implemented years ago in major centers such as St. John's. Despite being a global problem, personal transportation demand is unlikely to change in Newfoundland's future. National trends indicate an increase in the number of vehicles on Canadian roads (Environment Canada, 1996). To reduce vehicle emissions, it is crucial for Newfoundland to adopt a vehicle emissions control program.

Research is being conducted to encourage ride-sharing and enhance fuel efficiency per passenger kilometer in certain Canadian cities (Maddocks, 1996). Additionally, the exploration of alternative fuels, electric vehicles, hydrogen fuel cells, and revamped light-weight super fuel-efficient automobiles indicates the potential for significant improvements in energy efficiency and reduction of vehicle emissions. It is important to recognize that the issue of vehicle emissions extends beyond Newfoundland and requires global cooperation in research to address it. Municipal Solid Waste has shown an increase over the years, with projections suggesting that the average waste generated per person in New Brunswick will reach 550 kg by 1997, compared to approximately 350 kg in 1967 (Maddocks, 1996).

Solid waste is disposed of through small dump sites, large landfills, and incineration in Newfoundland. However, incineration, despite its space-efficiency, poses problems due to the global effort to reduce atmospheric air pollutants. All three waste management methods have their own issues. Landfills are being better managed and contained with improved design and site selection.

Ultimately, the only way to reduce solid waste production is by minimizing waste generation. Composting is effective for organic waste disposal, but regional composting faces site selection challenges due to public opposition. In Newfoundland, both land and sea persistent litter pose problems for aesthetics and marine animals, leading to entanglement and ingestion hazards.

The most effective solution to the problem is to reduce the amount of garbage generated per person. The national Packaging Protocol aims for a 50% decrease in packaging compared to 1988 levels by the year 2000 (Maddocks, 1996). These waste reductions have positive implications for solid waste management. The total Carbon Dioxide (CO2) emissions include oil and wood burning for home heating, fossil fuel refining for heating and gasoline engines, and electricity production (Maddocks, 1996). Despite Newfoundland power's efforts to promote electric heating, many people still rely on oil for their homes. Interestingly, furnaces powered by oil are more efficient than the electrical power station that supplies St. John's with electricity through oil combustion (Dawne, 1996).

Despite the fact that wood emits a high amount of carbon dioxide compared to its heat output in BTUs, it is still widely used as a primary heat source in rural areas of Newfoundland. However, given the harsh winters and the need for fuel efficiency, it is crucial to explore alternative fuel sources. Although fossil fuels are currently the most cost-effective option, economic factors will heavily influence the available choices. Nevertheless, there is potential to improve fuel efficiency and reduce carbon dioxide emissions by thoroughly investigating the feasibility of cleaner fuels such as natural gas. The economic benefits of finding a more environmentally friendly

and cheaper heat source cannot be overstated. Regardless of which fuel is chosen, it is essential to consider its environmental and economic impacts throughout its entire life cycle (from extraction and refinement to use).

The Newfoundland Department of the Environment classifies Primary Natural Resource Processing into two categories: Pulp and Paper Mills and Fish and Food Processing Plants. According to Whelan (1996), Mining and Smelting are not considered polluters by this department. Pulp and Paper Mills discharge effluents containing organic wastes and suspended solids into fresh and coastal waters. These effluents in Newfoundland produce various toxic organochlorine compounds such as dioxins and furans. The decomposition of wood also leads to the formation of organic acids, posing a problem with particulate matter. Consequently, the disposal of wood waste into rivers and bays in Newfoundland has created toxic carcinogenic habitats for fish (Whelan, 1996).

With the implementation of new regulatory measures, the environmental stress on waterways will be decreased. Although sulphur dioxide air emissions have been reduced, unpleasant odours still persist as an aesthetic issue. Recent technological advancements have made it possible to employ closed water systems in pulp and paper plants. However, the high setup cost prevents widespread adoption of this system. Closed water systems would effectively solve the problem of noxious odours and greatly reduce the need to discharge effluents into fresh and coastal waters.

Despite the availability of technology, the main concern regarding fish processing plants in Newfoundland is still the economics behind production. Since 1992, these plants have significantly reduced in operation and they pose a major threat to the environment by releasing high-strength oxygen-demanding wastes into coastal areas. The plant effluents

also contain harmful bacteria and create nuisance odours. However, the closure of many fish plants following the cod fishery moratorium in 1992 turned out to be a beneficial move for the environment and the cod fishery, as it addressed multiple issues surrounding the plants and their impact.

References:

1. Clair, T. 1996. Personal communication. Atmospheric Environment Service. Newfoundland Region, St. John's, Newfoundland. Dawne, L. 1996.
2. Personal communication. Jacques Whitford Environmental Consultants. St. John's Newfoundland. Hughs, R.N. 1991.
3. Acid Deposition in New Brunswick 1988-1990. New Brunswick Department of the Environment. Technical Report T-9001. April 1991. Maddocks, D. 1996
4. Personal communication. Newfoundland Environmental Management, Newfoundland Department of Environment and Lands. Newfoundland Region, St. John's, Newfoundland. New Brunswick Department of the Environment. 1991.
5. Report Relating to the Canada/New Brunswick Agreement Respecting a Sulphur Dioxide Emission Reduction Program for the Calendar Year 1990. Fredericton, NB. March 1991.
6. Newfoundland Department of Environment and Lands. 1991. Canada/Newfoundland Agreement Respecting a Sulphur Dioxide Emission Reduction Program Report. St. John's, Newfoundland. March 1991.
7. Nova Scotia Department of the Environment. 1991. Canada/Nova Scotia Acid Rain Reduction Agreement Report on the Year ending 31 March 1991. Halifax, NS. March 1991. Porter, K. 1996.
8. Personal communication. Atmospheric Environment Service. Newfoundland Region, St. John's, Newfoundland. Power, K. 1996. Personal Communication.
9. Environmental Protection, Environment Canada, Atlantic Region. St. John's, Newfoundland. Ryan, P. 1996. Personal communication. Department of Fisheries and Oceans (DFO).