Troposphere - It is found at the Earth’s surface. - Ozone in this area is “bad” because it dirties the air and helps make smog, which is unhealthful to breathe.- It is a layer miles above the Earth’s surface. - Ozone in this area is “good” because it absorbs some of the sun’s ultraviolet rays. - It is the region where the ozone layer is located.
but these are all part of a natural cycle where ozone is continually formed, destroyed and formed again.
ODS are very stable, nontoxic and environmentally safe in the lower atmosphere, which is why they became so popular in the first place. However, their very stability allows them to float up, intact, to the stratosphere. Once there, they are broken apart by the intense ultraviolet light, releasing chlorine and bromine.
The impact on marine ecosystems, especially on phytoplankton and larvae of higher organisms , are of particular concern. Damage in the food chain, 30 percent of the world’s animal protein comes from the sea Damage in the oceanic carbon cycle by which atmospheric carbon dioxide is converted into oxygen. Reduced terrestrial plant productivityReduced food security and food quality Changes in microbial biodiversity with consequences for soil fertility and plant disease. Numerical models predict that future changes in UV radiation and climate will modify the trends and geographic distribution of hydroxyl radicals, thus affecting urban and regional photochemical smog formation, as well as the abundance of several greenhouse gases. The impacts of air pollution on human health and the environment will be directly influenced by future changes in climate, emissions of pollutants, and stratospheric ozone. Today's materials are somewhat protected from UVB by special additives. Therefore, any increase in solar UVB levels will therefore accelerate their breakdown, limiting the length of time for which they are useful outdoors.
Phils. Signed the protocol- Jan 1, 1989-agreed on 16 September 1987 and entered into force on 1 January 1989
Republic Act 6969 or the Toxic Substances and Hazardous and Nuclear Wastes Control Act. This Act mandates the regulation, restriction, or prohibition of the importation, manufacture, processing, sale, distribution, use and disposal of chemical substances and mixtures that present unreasonable risk and/or injury to health and the environment. paved way for the control and regulation of dioxins and furans releases to the air.
provides the requirements that contributes to the reduction of the emission of dioxins and furanscreated Fertilizer and Pesticides Authority an agency that mandates to regulate and monitor production, importation and use of pesticides and other agricultural chemicals in the country.
Ozone layer depletion ppt
• Troposphere• Stratosphere
• Ozone layer is a thin, fragileshield that contains relatively highconcentrations of ozone.• It shields the entire Earth frommuch of the harmful UV radiationthat comes from the sun
• Damage in the ozone layer willnaturally mean the entry of harmfulrays in to the atmosphere.• In the 1970s, the scientistsdiscovered that the ozone layeris being depleted.
• seasons• weather conditions, and• solar cycles
Ozone layer is being destroyed by a group of manufacturedchemicals that are called ODS orOzone-Depleting Substances.
The main ODS are the following:• Chlorofluorocarbons (CFC 11, CFC 12, CFC 13)• Methyl bromide (CH3Br)• Halons (halon-1211, halon-1301, halon-2402)• Carbon tetrachloride (CCI4)• Hydrochloroluorocarbons (HCFC 22 and HCFC123)
The Principal Steps in Stratospheric Ozone Depletion Caused by HumansEmissions Accumulation Transportation ChemicalRemoval Conversion Reaction
When an ozone hole was discovered,several countries unite to prevent thecontinuous depletion of the ozone layer byimplementing policies and other preventivemeasures.• The Montreal Protocol on Substancesthat Deplete the Ozone Layer
Philippines’ Laws and Policies• Republic Act 6969 or the ToxicSubstances and Hazardous andNuclear Wastes Control Act.• Republic Act 8749 or thePhilippine Clean Air Act of 1999
• Republic Act 9003 or the Ecological SolidWaste Management Act.• Presidential Decree 1144
Davao City has also implementedmitigating measures. The LocalGovernment implemented the Davao CityEcological Solid Waste ManagementOrdinance 2009 (Section 7, Article 5 of theOrdinance 0361 series of 2010) - that provides the use of recyclable,biodegradable or reusable containers asfood and beverage parcels started 28 June2012.
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