The ozone layer and atmospheric protection

Ozone Layer

Factors, Impacts

The ozone layer is a spread of blue-colored gas through the stratosphere, which filters out ultraviolet radiation from the sun (Lean 2005). No life on earth is possible without it.

But chemicals, like chlorofluorocarbons or CFCs, and other pollutants, have weakened the protective layer and created a hole. The hole, first recognized in 1987, is as big as the U.S. And as high as Mount Everest. It allows radiation to cross the stratosphere and cause skin cancer and cataracts, damage plant and destroy plankton. The hole opens over Antarctica, which is largely uninhabited and, thus, poses little threat on living things (Lean). Scientists in the 70s first discovered the damaging effects of CFCs and other chemicals on the zone layer (Baker 2000). The discovery was substantiated by the finding of the ozone hole in 1987. Additional studies said that ozone depletion and increased ultraviolet radiation could afflict human health and environment (Baker).

Scientists of EU SCOUT-03 Project found large areas of polar stratospheric clouds from the ozone layer over the Arctic region (Amodeo 2005). They said that the clouds could be at altitudes of around 20 kilometers and more extensive than previously believed. They described the conditions as similar and even surpassing those of the 1999- 2000 winter, during which the worst ozone depletion was noted. The spokesman was Dr. Neill Harris of the Cambridge-based European Ozone Research Coordinating Unit and one of its coordinators. He added that the low temperatures over the region were expected to result in significant thinning of the ozone layer (Amodeo).

There are two different types of ozone layers (Baker 2000). These are the stratospheric ozone and the tropospheric ozone. The stratospheric ozone is the "good" ozone, which moves 10-30 miles above the earth. It consists of "good gas," which shields the earth from harmful ultraviolet rays of the sun. The tropospheric ozone is the bad one, which consists of the by-products of fuel combustion and smog. It is found in the lower atmosphere at roughly 10 miles above the ground. It can damage the lungs permanently and interfere with the plants' functions of producing and storing food. These two types do not collide or mix. The tropospheric ozone cannot ascend into the stratosphere. Increasing bad ozone will not help repair the impaired good ozone layer. It will create more health problems. The lack of science education is deemed still weak at present (Baker).

Recent Trends

Presence of these clouds would significantly disturb chemical balance in the stratosphere, Dr. Harris said (Amodeo 2005). The chemical imbalance would rapidly destroy the ozone layer in the presence of sunlight. If the region's stratosphere remains cold in February and March, substantial loss of ozone can occur as sunlight returns to northern latitudes. Increased levels of ultraviolet radiation can then spill over inhabited areas of Northern Europe (Amodeo), Britain, North America and Russia (Lean 2005). This has not happened because the Arctic does not get as cold as the Antarctic. But lower temperatures and more "polar stratospheric clouds" have been observed a few years back. Polar stratospheric clouds indicate ozone depletion, which is the consequence of pollution on earth. Dr. Harris noted that ozone levels in the Arctic had gone 40% lower than normal in the Arctic region. Scientists have not formed a consensus on the likelihood of a hole developing over the region. If it does, the risks would depend on weather conditions and other local factors, according to Dr. Harris. While clouds shield life from the sun's radiation, sunny days would expose it. At the worst, he said the feared depletion of the ozone layer would not be as critical as that over the Antarctic region. He observed that the cold vortex, which forms the ozone hole, remains in the same place in the Antarctic region. In comparison, that in the Arctic region moves around. The vortex in the Antarctic is over northern Europe, including Britain, at present (Lean). In September 1998, however, the World Meteorological Organization said that the hole was 27 million square miles, larger than North America. It also deeper and could be more threatening to human health than earlier believed (Lean). In October 2000, a major ozone hole was found open for the first time over Punta Arenas, Chile, a thickly populated area (Baker 2000).

Measurement, Policies, Benefits

By the year 2000, more than 173 countries, including the U.S., had signed the Montreal Protocol of 1987 (Baker 2000), in reaction to the fatal environmental threat. It is a global agreement to phase out the use of ozone-depleting chemicals. It consisted of timetables for every country to stop producing CFCs. In the U.S., Congress amended the Clean Air Act to adjust to the goals of the Protocol. In 1987, it called only for a partial phase-out of the chemicals, but upon evaluations in 1989, a total phase-out was found necessary. Evaluations in the 1990s found the need to drastically phase out new chemicals hydrochlorofluorocarbons or HCFCs and methyl bromide. But there stood the crucial problem of time in addressing the global threat on life in the planet (Baker).

Kert Davies, science policy director of Washington DC-based interest group, called Ozone Action, commented on the length of time it took for an international treaty like the Protocol to really move (Baker 2000). By the time it did, scientific updates on ozone depletion had increased. The Protocol's scientists said that, without this global agreement, the world in 2050 would be dismal. Ozone would have been at least 50% at mid latitudes. Surface ultraviolet radiation would be more than double at mild latitudes in the Northern Hemisphere and four times at mild latitudes in the Southern Hemisphere. Approximately 19 million more non-melanoma skin cancer cases and 1.5 million more melanoma skin cancer cases should be expected by the year 2060. Unquantifiable cases of lower immunity to disease, reduced crop productivity and damage to aquatic ecosystems could also be expected (Baker).

There too is a political obstacle to the effective and prompt implementation of Protocol goals. Under the terms of the Montreal Protocol, developing countries have delayed phase-out schedules for ozone-depleting chemicals. Industrialized countries had up to 1996 for CFCs and methyl bromide by 2005. But developing countries' deadlines were 2010 for CFCs and 2015 for methyl bromide. Chief officer Omar El-Arini of the United Nations Multilateral Fund Secretariat in Montreal said that developing countries still consume around 200,000 tons of these toxic chemicals. His group was established in 1990 to help developing countries comply with the terms of the Protocol. He stressed that these countries' cooperation was certainly necessary in the global effort to make the ozone layer recover (Baker).

Costs

There are obstacles in the form of legal violations right at home. One was that by a certain Bert Ammons of Stuart, Florida for smuggling 90 30-pound cylinders of Freon (Baker 2000). Freon contains CFC-12. Environmental Protection Agency officials said that Ammons intended to distribute these items to auto repair shops around Fort Lauderdale. His cargo was worth approximately $68,000. Violations do not end there. It was reported that, between 1994 and 1997 alone, 6,367 tons of CFC-12 and 24 tons of CFC-113 as a fire suppressant were smuggled into the U.S. This was equivalent to $43 million of attempted tax evasion. The EPA Criminal Enforcement Division also said that illegal CFCs were the second most profitable smuggled items. Jack McQuade of the U.S. Customs Service said that smuggling CFCs into the U.S. had become a serious problem. Compounding deleterious consequences, not only did developing countries continue to produce CFCs: they were also quite inexpensive. In Mexico and China alone, CFC-12 $2 sold for only $1 or $2 a pound and could be resold in the U.S. At $20 or $25, depending on the balance of supply and demand (Baker).

The importation of CFCs and other ozone-depleting chemicals were banned in the U.S. In 1996 (Baker 2000). But millions of equipment using CFCs have remained in use. These include most automobiles built before 1994, air-conditioners and refrigeration equipment. Alternatives could cost a few hundreds to thousands of dollars. Furthermore, the U.S. And other industrialized countries allow the business and use of recycled CFCs in order to use existing machinery. It is extremely difficult to recognize new from recycled Freon. As a result, unscrupulous traders could bring in CFCs into industrialized countries as recycled goods or export these to developing countries. The high excise tax a $5.35 per pound encourages illegal trade of CFCs (Baker).

Benefits and Status of Interventions

Former U.S. President Bush set out more radical proposals to abate global warming more than the Kyoto Protocol had intended (Lean 2007). The "greenhouse effect" means the warming of the lower atmosphere (Baker 2000). It traps warm air at the surface. In turn, the upper atmosphere cools. This sets the condition for the depletion of the ozone layer. CFCs both deplete the ozone layer and conduce to global warming (Baker). Former President Bush's government urged for the phase-out of gas emissions, which cause climate change (Lean 2007). His government wanted HCFCs to replace CFCs. HCFCs are far less damaging to the ozone layer. They are used in refrigeration. He proposed that the deadlines for the cessation of the use of CFCs be advanced by a decade. The global agreement was to phase out CFCs among industrialized countries by 2030 and among developing countries by 2040. It was also later discovered that HCFCs warm up the earth a lot faster than carbon dioxide (Lean). HCFCs were first assumed to be beneficial alternatives to CFCs (Baker 2000). These chemicals were found to be potent greenhouse gases, which heat up the earth up to 4,000 times more than carbon dioxide (Lean).

The Montreal Protocol was successful in immediately phasing out ozone-depleting chemicals, such as CFCs, by replacing them with less damaging alternatives (Sengupta 2005). Manufacturers of fire extinguishers and refrigerators could be commended for their response. But the real effects of that response will not be evident until after many years, as CFCs remain in the atmosphere for long periods. These chemicals create the greatest damage in the Antarctic region because of its unusual weather. High-altitude clouds form best at those levels and thus enhance the conditions and reactions, which destroy the ozone layer. The weather influences changes in the size of the hole from one year to another. It first appeared to be shrinking at the start. But in 2003, it grew to a record size. Then it grew smaller, an indication of rapid repair. Despite this trend, Jonathan Shanklin of the British Antarctic Survey said that hole would not disappear completely until the middle of the century, at the earliest (Sengupta).

The analysis of the first and second Stratospheric Aerosol and Gas Experiment or SAGE and the Halogen Occultation Experiment or HALOE offered evidence for the first stage of ozone layer recovery (Steitz 2003). In 1997, scientists found less ozone depletion in the upper stratosphere at 22-28 miles altitude. The decrease was consistent with the reduction of man-made chorine and bromine-containing chemicals. These changes were documented by satellite, balloon, aircraft and ground-based measurements. Associate Professor Mike Newchurch of the University of Alabama and lead scientist in the SAGE II-HALOE study said that total ozone recovery would take decades. More information was needed, such as the effect of climate change on ozone recovery. SAGE I was launched in 1979 on the Applications Explorer Mission B. spacecraft. SAGE II was launches in 1984 on the Earth Radiation Budget Satellite. HALOE was carried by the Space Shuttle Discovery on the Upper Atmosphere Research Satellite in 1991. The research was funded by the National Aeronautics and Space Administration's Science Enterprise in order to better understand and protect the earth. Ozone depletion not only allows the sun's ultraviolet rays into the earth and threatens health and life. It also causes the ozone hole over Antarctica every spring (Steitz).

Policies in Reducing Ozone Depletion and Forecast

Measurements provided by the three satellites and three ground stations confirmed the slowing down of ozone depletion in the past decade (Connor 2003). But Professor Newchurch emphasized that it would take at least half a century before the ozone layer could completely repaired. He and fellow scientists acknowledged the success to the Montreal initiative of 1987 to phase out the production of CFCs in products, such as aerosol sprays and refrigerators. It is the chlorine content in CFCs, which destroys the ozone layer. He said that ozone depletion was declining at roughly 8% per decade. At that time, the depletion was only at about 4% per decade (Connor).

Despite the first indication of recovery, Professor Newchurch stressed that ozone-depleting chemicals should be produced again (Connor 2003). The harmful ultraviolet light produced by the sun is naturally destroyed in the absence of pollution. But the chlorine in CFCs is far more destructive than pollution alone. It is responsible for large-scale ozone destruction in the polar regions at the end of winters when sunshine induces photochemical reactions (Connor).

California Congressman Richard Pombo introduced the Methyl Bromide Fairness Fact (Baker 2000). It focused wide-scale attention on methyl bromide, a toxic and ozone-depleting chemical used primarily by California strawberry and Florida tomato farmers. The Act would postpone U.S. phase-out deadline to 2015. This was the deadline for developing countries to stop producing and consuming the chemical. It is already banned in many countries, including the Netherlands and Canada. Methyl bromide has been linked to almost 500 cases of poisoning since 1982 in California. Of this number, 19 were fatal. The government and the scientific community agree that the use of methyl bromide compounds should be regulated. The EPA categorizes methyl bromide as a Class I ozone-depleting chemical, scheduled for phase-out by the Clean Air Ac. The United Nations Environment Programme said that the phase-out of CFCs and the removal of methyl bromide emissions from industries and agriculture would be the single important step by the world's governments to reduce ozone depletion. Bill Thomas of the EPA's Stratospheric Protection Division commented about farmers' reluctance in changing their crop rotation systems. These have been developed around methyl bromide. But there are effective substitutes, which would allow them to continue crop production in ways they have been used to (Baker).