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International Day for the Preservation of Ozone Layer 30 years of healing the ozone together Ozone: All there is between you and UV 16th September 2015 Naresh Thakar, Former PRO, GPCB, [email protected] 16th September 1987, representatives from 24 countries met in Montreal and announced to the world that it was time to stop destroying the ozone layer. They committed themselves, through the Montreal Protocol on Substances that Deplete the Ozone Layer, to rid the world of substances that threaten the ozone layer. Thus, 16th September, commemorates the date of the Montreal Protocol signing on Substances that Deplete the Ozone Layer which is observed as International Day for the Preservation of Ozone Layer, as per resolution adopted by the United Nations General Assembly in 1994. This current year is 30th Anniversary of Montreal Protocol parties move closer to managing hydrofluorocarbons under mostsuccessful Environmental Treaty. The theme for the celebration of both the anniversary and the International Day for the Preservation of the Ozone Layer is, ‘30 years of healing the ozone together’, and the slogan is ‘Ozone: All there is between you and UV’. Ozone: Ozone (O3) is a gas found in Earth’s atmosphere. Each ozone molecule is made up of three oxygen atoms. It is a pale blue gas with a distinctively pungent smell and very scarce. Just 0.000004 % of Earth’s total atmosphere is made up of ozone. The formation of ozone is continuous natural process. Plantation plays an important role in rejuvenate the ozone through UV rays’ action. Tropospheric ozone: Near Earth’s surface, ozone is produced by chemical reactions involving naturally occurring gases and gases from pollution sources. Ozone production reactions primarily involve hydrocarbon and nitrogen oxide gases, as well as ozone itself, and all require sunlight for completion. Stratospheric ozone: Stratospheric ozone is formed naturally by chemical reactions involving solar ultraviolet radiation (sunlight) and oxygen molecules, which make up 21% of the atmosphere. Ozone reacts continually with sunlight and a wide variety of natural and human produced chemicals in the stratosphere. Important reactive gases that destroy ozone are hydrogen and nitrogen oxides and those containing chlorine and bromine. Ozone helps us: The stratospheric ozone layer protects life on earth by absorbing most of the harmful ultraviolet radiation from the sun. Ozone Layer: The ozone layer is a layer in the Earth's atmosphere containing high concentrations of ozone. It occurs between about 20 and 30km above the Earth's surface without definite edges. The ozone gas assembles within the middle reaches of the stratosphere. The ozone layer protects us from harmful radiation from the sun’s UVB ultraviolet radiation. Small amounts of exposure to UVB can result in sunburn, but high levels of exposure would cause human beings and most other life on earth to die. Ozone is an unstable and reactive gas. The ozone in atmosphere is very dynamic - it is being created and destroyed all the time. When UV light passes through the ozone layer, oxygen molecules are split up into their constituent oxygen atoms. These single atoms are then able to react with other oxygen molecules, forming ozone. This process is an endothermic reaction, it needs to absorb energy. This also happens in reverse - because ozone is so unstable, each ozone molecule soon splits into an oxygen molecule and an oxygen atom. This is an exothermic reaction. This means that ozone splitting results in heat 1 which causes an increase in atmospheric temperature. Ozone layer - damage and effects: It was discovered in 1970s that some manmade products destroy ozone molecules in the stratosphere. Over 95 chemicals such as chlorofluorocarbons (CFCs), halons, carbon tetrachloride, methyl chloroform, etc. identified as responsible to damage ozone layer. Chlorine atom liberated from various ODS- Ozone Depleting Substances reacts with ozone and forms chlorine oxide and oxygen gas. Again, chlorine oxide reacts with one oxygen atom available in the atmosphere and forms chlorine atom and oxygen gas. Thus, liberation of such chlorine atom becomes chain reaction and destroy ozone molecule, one after another. This led in damage to ecosystems. It may cause an increase in human diseases such as skin cancers and cataracts. UV-radiation affecting the immune system: The immune system can be altered by UV irradiation, leading to diminished immune responses to infectious agents and skin cancers. CFCs alternate: The hydrofluorocarbons (HFCs) do not deplete the ozone layer. They are potent greenhouse gases and many of them have high global-warming-potential. They have a smaller effect on the ozone layer. HFCs are used in the air conditioning, refrigeration, foam and aerosol sectors as replacements for many ozone-depleting substances (ODSs). Green House Gases: By absorbing the infrared radiation emitted by the earth, some gases control the way natural energy flows through the atmosphere. Such gases are known as greenhouse gases. Carbon dioxide, although only a tiny fraction of the atmosphere, methane, nitrous oxide, hydrofluorocarbons, sulphur hexafluoride, perfluorocarbons are identified as greenhouse gases. Supported by: Ozone depletion and climate change: The climate change will affect ozone depletion. It affects loss in stratospheric ozone. Climate change is expected to decrease temperatures and water vapour abundances in the stratosphere. Climate change is reportedly occurs especially due to carbon dioxide among other gases. Global actions: Since, 1985, the nations of the world participated in the Vienna Convention implementation of the Protocol over the years, leading to a 98% reduction of the ozonedepleting chemicals and strengthened historic baseline levels of the ozone-depleting substances produced and consumed globally. Worldwide, over 260 thousand tons of ODS production is discontinued, permanently. Significant financial assistance is provided to developing countries. This year is also being the 30th anniversary of the Vienna Convention for the Protection of the Ozone Layer. It is an important milestone in the protection of the ozone layer mission. Phytoplankton are single-celled marine plants that support marine life. They also moderate the global greenhouse effect by absorbing carbon dioxide from the atmosphere and releasing sulphur compounds to promote cloud formation. Now, as the ozone hole is healing, the phytoplankton is flourishing in the microbial community! Climate change and Cleanliness: Now, the Ozone is healing due to commitment made worldwide against ODS, we too can take a leaf out of it and do a little to reduce among greenhouse gases, e.g. carbon dioxide being emitted daily around each and every municipal locality as solid wastes is being dumped and burnt. And also support community plantation as both also help against climate change. : 10th September 2015 Indroda Nature Park, P.O. Sector -7, Gandhinagar 382 007,Gujarat Tel: (O) +91-79-23221385, +91-79-23226829 Fax: +91-79-23241128, E-mail :[email protected] Website :www.geerfoundation.gujarat.gov.in 2