Protecting Our Earth :: Weekly Blitz

September 16 every year is observed as 'International Ozone Day'. The celebration of this day is made to pay our attention to the ozone layer that saves our Earth from the harmful ultra-violet radiation of the Sun. The theme for this year's (2011) celebration is 'HCFC phase-out: a unique opportunity'. This year is also the 20th anniversary of the Montreal Protocol, the 19th Meeting of the Parties agreed to accelerate the phase-out of production and consumption of hydro chlorofluorocarbons (HCFCs). The call of the United Nations to world's governments is to commemorate the Day protecting the ozone layer (shielding Earth from damaging ultraviolet rays), and to present countries with a unique opportunity to select cutting-edge technologies that eliminate ozone depleting substances (ODS) while reducing national energy costs and maximizing climate benefits.

Scientists predict that by allowing more UV radiation to reach the earth, the depletion of the ozone layer will lead to an increase in the number of cases of skin cancer (especially melanoma) and cataracts. In addition, they assume that the increased UV radiation may damage crops, kill plankton that serve as a food source for marine life, and even have adverse effects on the human immune system. CFCs may also trap heat in the atmosphere and thus contribute to the global warming trend (greenhouse effect). For all these reasons, an international agreement in Montreal in 1987 called for phasing out CFC and halon production. Recent reports by NASA that the ozone layer is being depleted even more rapidly that was previously projected, and the discovery of vast holes in the layer over Antarctica and the Arctic, have prompted scientists and environmental groups to call for a complete and rapid phase out of CFCs. But the fact remains that even if we stop using CFCs, the damage to the ozone layer will continue, since those CFCs already released into the air will still be making their way to the stratosphere a decade from now and destroying the ozone for up to a century.

Thomas Midgley Jr., a U.S. scientist invented CFCs in the 1920s. They were used in air conditioning/cooling units, as aerosol spray propellants prior to the 1980s, and in the cleaning processes of delicate electronic equipment. They also occur as by products of some chemical processes. No significant natural sources have ever been identified for these compounds−their presence in the atmosphere is due almost entirely to human manufacture. In the ozone cycle, when such ozone depleting chemicals reach the stratosphere, they are dissociated by ultraviolet light to release chlorine atoms. The chlorine atoms act as a catalyst, and each can break down tens of thousands of ozone molecules before being removed from the stratosphere. Given the longevity of CFC molecules, recovery times are measured in decades. According to scientists, a CFC molecule takes an average of about five to seven years to go from the ground level up to the upper atmosphere, and it can stay there for about a century, destroying up to one hundred thousand ozone molecules during that time.

If the ozone layer continues to be depleted by human action, the effects on the planet could be catastrophic. Ozone is present in the stratosphere. The stratosphere reaches 30 miles above the Earth, and at the very top it contains ozone. The sun's rays are absorbed by the ozone in the stratosphere and thus do not reach the Earth. Ozone is a bluish gas that is formed by three atoms of oxygen. The highest regions of the stratosphere contain about 90 per cent of all ozone. In recent years, the ozone layer has been the subject of much discussion. And rightly so because the ozone layer protects both plant and animal life. Ozone depletion both at atmospheric or lower atmospheric levels is known to be extremely hazardous for human health. It can worsen asthma, lead to lung function impairment and damage lung tissues, chest pain, coughing, nausea, headaches and chest congestion, heart disease, bronchitis and emphysema. Even, it can kill and make people seriously ill if it increases even for a short duration during the day.

But the ozone hole is a completely different phenomenon to global warming. However there are links between them. This hole is caused by ozone depleting chemicals in the atmosphere, which have been produced by industry, for example CFCs. One link is that CFCs are also 'greenhouse gasses'. Enhanced global warming is a probable consequence of increasing amounts of greenhouse gasses, such as carbon dioxide and methane, in the atmosphere. Although the surface of the earth warms, higher up the atmosphere cools, thus increasing the area where stratospheric clouds can form. This makes a larger area susceptible to ozone depletion and provides another link between the two issues. Humans can take two broad steps towards reducing CFCs:

Reducing emissions of nitric oxide, methane and sulfur dioxide
Reducing emissions of chlorofluorocarbons

Because CFCs are so widespread and used in such a great variety of products, limiting their use is hard. Also, since many products already contain components that use CFCs, it would be difficult if not impossible to eliminate those CFCs already in existence. The problem may be hard to solve because there are already great quantities of CFCs in the environment. CFCs would remain in the stratosphere for another 100 years even if none were ever produced again. International action has been taken to limit CFCs. In the Montreal Protocol, nations worldwide agreed to reduce usage of CFCs and encouraged other countries to do so as well.

Reducing emissions associated with combustion such as oxide, methane and sulfur dioxide will help the ozone layer to recover because this compounds cause depletion of ozone in the stratosphere (the part of the atmosphere were the ozone layer is) by reacting with ozone or by elements that are needed to create ozone. CFCs are potentially dangerous to the ozone layer because they are stable compounds able to travel all the way up to the ozone layer without reacting with anything on the way. CFCs are especially bad because there is no natural source at all.

Substitutes have already been found for certain uses of CFCs. For instance, the U.S. Environment Protection Agency (EPA) banned the use of CFCs as propellants in most, but not all aerosol sprays in 1978. CFCs can be modified so they do much less damage to the ozone layer, or so that they break down quickly in the lower atmosphere. Industries are also seeking ways to recycle the chemicals so that they aren't released into the air.

But despite nations' efforts to phasing out ODS, dismal scenario prevails too. A very recent World Meteorological Organization estimation revealed that the depletion of the ozone layer has reached an unprecedented low over the Arctic this spring because of harmful chemicals and a cold winter. The Earth's fragile ozone layer in the Arctic region has suffered a loss of about 40 per cent from the start of winter until late March, exceeding the previous seasonal loss of about 30 per cent, the U.N. Weather agency claimed. The loss comes despite the U.N. ozone treaty, known as the 1987 Montreal Protocol, which has resulted in cutbacks in the use of ozone damaging chemicals in the making of refrigerators, air conditioners, fire extinguishers and even hairspray. Chlorofluorocarbons (CFCs) and other halogenated ODS are mainly responsible for manmade chemical ozone depletion.

Bangladesh accessed the Montreal Protocol on 2 August 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. Phasing out the ODS in manufacturing sectors, especially refrigeration sector is currently in progress in the country which is being carried over by the Department of Environment. So far the country has achieved some success in this sector to meet the target set for the country by the Montreal Protocol. Towards achieving a slow but effective protection we can follow some simple things. As mentioned already, air conditioning, refrigeration and propellants are the main culprits for causing damage to atmosphere. And these are mainly used by the affluent classes of the society and they can afford maintenance and repair of these items. Establishment of the norm of maintenance and caring doesn't require massive awareness about the environment, it simply requires users' realization of the bad effects of ODS. Holistic approach to the following protocols would definitely reduce CFCs and would remind us of our commitment to reducing pollution, prove our worth in the overall conservation process.

To efficiently deal with this fearsome situation, we have to take stringent steps:

-Save trees as they save life by inhaling harmful gas carbon dioxide.

-More sustainable behaviour in our daily lives like saving energy at every step.

-To use technologies which are environment-friendly, like bio fertilizers.

-The expansion of carbon trading by the developed countries from developing countries.

-Globalize the technologies to the under developed nations that supports the climate.

-Have your car's air conditioners carefully serviced

-When buying a refrigerator, choose an energy efficient model: or buy ozone-friendly one

-Do not buy a halon fire extinguisher for home use

-Check labels on aerosol cans

-Buy energy saving bulbs. You will reduce levels of pollution and money, etc.

But much more is needed to do in this sector for contributing to the global conservation effort to leave a cleaner future for the present and next generations. We can reduce daily load by changing our lifestyle and initiating a paradigm shift in our habits. We need act before it is too late.

Related Topics: Op-Ed and Editorial receive the latest by email: subscribe to weekly blitz's free mailing list

Protecting Our Earth

Comment on this item