Air Pollution & Air Quality Monitoring Chapter 1

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<ul><li><p>Air Pollution &amp; Air Quality Monitoring</p><p>Chapter 1</p></li><li><p>AssessmentWritten Tests (2) 50Practical Reports (min 5)40Assignment10In order to pass this subject you will be required to obtain a minimum of 60% for both tests and hand in 5 practical reports.Assessment will be competency based with grades of A, B, C, and NC (not competent).</p></li><li><p>Introductionfunctions of the atmosphere include:protection from harmful radiationmoderating the surface temperature providing a medium (air) that allows organisms to exchange gases in order to survive (breathing). </p></li><li><p>IntroductionAny substantial change in the nature or contents of the atmosphere has a direct consequence on how well the atmosphere performs these tasksAre there any current scenarios that this relates to?</p></li><li><p>IntroductionHistorically air pollutants of greatest concern have been TSP, and oxides of sulfur, More sophisticated processing industries = longer list of significant pollutants NOx and photochemical oxidants as routine pollutants, and often include Pb, asbestos, Hg, H2SO4 and many others that require careful monitoring. </p></li><li><p>IntroductionNon-pollutants e.g. CO2 also a problem Wastes released into the atmosphere are diluted and dispersed in the air, and are processed and recycled through a variety of natural physical, chemical and biological mechanisms. the atmosphere is continually cleaned of pollutants</p></li><li><p>IntroductionAtmospheric problems are made worse by weather conditions The residence time determines significance of pollution problemcompared to natural sources, mans activities produce a much smaller amount of global pollution. </p></li><li><p>Introduction</p><p>Chart2</p><p>4842</p><p>9010</p><p>955</p><p>991</p><p>955</p><p>937</p><p>% Emissions from Natural Sources</p><p>% Emissions from man made sources</p><p>Pollutant</p><p>Global Emissions form Natural &amp; Man Made Sources</p><p>Sheet1</p><p>Pollutant% Emissions from Natural Sources% Emissions from man made sources</p><p>SOx4842</p><p>CO9010</p><p>NOx955</p><p>NH3991</p><p>H/C955</p><p>Dust937</p><p>Sheet1</p><p>% Emissions from Natural Sources</p><p>% Emissions from man made sources</p><p>Pollutant</p><p>Global Emissions form Natural &amp; Man Made Sources</p><p>Sheet2</p><p>Sheet3</p></li><li><p>IntroductionDispersal of pollutants is a very important consideration as the atmosphere is not homogeneous - pollutants tend to concentrate in specific areas most of which are near where large human populations residemeans that pollutant levels around residential areas are often much greater than would be expected in ambient air </p></li><li><p>IntroductionNatural sources are in general more evenly spread, but there are exceptions such as extremely high levels of dust and acidic gases associated with volcanic activity.Man's activities (anthropogenic) release heat, gases, aerosols and other wastes into the atmosphere in high conc's overloading the natural dispersal, dilution and recycling systems </p></li><li><p>IntroductionVery little is known about the dispersal processes and the passage through ecological systems of pollutants. Many are resistant to degradation, some are cumulative and harmful.</p></li><li><p>IntroductionAir pollution definitionWHOAir is polluted when one or several pollutants are present in the atmosphere at such a conc. and for so long a time that they are harmful to man, animals, plants or material property, cause harm or reduce well-being or disturb appreciably its application. </p></li><li><p>IntroductionNSW Protection of the Environment Operations Act as any deviation from the natural combination of gases in our atmosphere. </p></li><li><p>IntroductionDefinition fails to mention is that the natural combination of gases in our atmosphere must be taken as dry air at sea level. Neither completely cover other factors that we might also call pollution such as the release of energy, radiation, odour or noise. </p></li><li><p>IntroductionMost air pollution concerns are associated with ambient air (outdoors and free flowing) hence most control programs focus on ambient air pollution, significant pollution now occurs in occupational environments which are indoors. </p></li><li><p>The AtmosphereEarths atmosphere 160 kilometers deep, 95% of air mass lies within 20 kilometers of the surface. atmosphere is neither uniform, nor static in nature. Its characteristics vary widely with altitude, season, location and solar flare activity. Air within a few kilometers of the earths surface will typically contain the components </p></li><li><p>Element% (by volume) in the atmosphereTotal Mass in the Atmosphere (x1012 tonnes)nitrogen78.083900oxygen20.951200argon0.93467carbon dioxide0.0352.5Neon0.00180.065Helium0.000520.004Methane0.000150.005Krypton0.00010.017Carbon Monoxide0.000010.0006Ozone0.0000020.0003Nitrogen Dioxide0.00000010.000013Sulfur Dioxide0.00000010.000018water0.1 5 (normal range 1-3)Varies according to location</p></li><li><p>The AtmosphereThe pollutants with which we have the most problems make up an extremely small part of the atmosphere. In polluted city areas these % conc's will change markedly for some pollutants.The conc's of N, O, Ar, Ne, He, Kr, H and Xe remain essentially constant (most are inert and play little or no role in atmospheric chemistry). </p></li><li><p>The AtmosphereN is a precursor for other species such as NO3-, as well as amino acids and nucleic acids (amongst others) which are essential for life, and reacts with O. O2 important for the nurturing of life, and forming ozone (O3), acts as a heat and radiation shield for the planet maintaining fairly constant temperatures that allow life to exist.</p></li><li><p>The AtmosphereAt 0.035%, CO2 in the atmosphere is very low - enormous significance as the raw material used by plants for carbon fixation to produce the compounds used for energy by almost all forms of life. also a significant greenhouse gas which serves to keep the planet warm.Water vapour is the most variable (from 0.1 30,000ppm). allows the transport of energy around the planet. </p></li><li><p>The AtmosphereForms clouds that are responsible for the Earths albedo the ability of the Earth to radiate sunlight back into space controlling the Earths surface temperaturetrace gases produced from biological or geological processes, NH4, CH4, H2S, CO and SO2</p></li><li><p>The AtmosphereThe avg. person breathes 20,000L of air per day995 of which is N or O. 1% is a mixture of gases and particulates, many of which are pollutants. we breathe as much as 200L of pollutants per day!</p></li><li><p>Stratification of the Atmospherestratification or layering of the atmosphere 95% of the atmospheres air mass is found in the troposphere. The upper troposphere has a temperature of -56C.At the top of the troposphere is the tropopause layer - a barrier to prevent water vapour rising much higher as it causes ice formation. Water vapour cannot pass through it. stratosphere, - The ozone layer is within the stratosphere, and reaches levels of up to 10ppm in the middle of the stratosphere gets hotter due to this.</p></li><li><p>The Atmosphere</p></li><li><p>The history of air pollutionAir pollution was probably as much a problem to cave men as it is today. Reports of air pollution and decimation of forests have been recorded since the 14th C. mostly linked with the burning of soft coal with a high sulfur content. This activity produces smoke, sulfur dioxide and particulate matter containing HCs. </p></li><li><p>The history of air pollutionLondon "pea souper" fogs. type of smog is grey in colour and is generally referred to as London type smog. Meuse Valley of Belgium 60 deaths. 21 people were killed in Donora, Pennsylvania, Most victims died of lung and breathing disorders. Of the survivors, 7000 of the total population of 14000 became seriously ill. </p></li><li><p>The history of air pollutionLos Angeles type smogs conditions different to those in London Large amounts of NO2 and unburnt HCs, which then react in the atmosphere in the presence of UV light and oxidants to form a brown photochemical smog. </p></li><li><p>Haze or smog?Haze, but how is it different to smog? Both typified by a reduction in visibility, but the intensity varies. Haze is a condition where the reduction in visibility is not great, and is generally applied to describe the atmospheric conditions over a very large area Smog is significant reductions in visibility, generally in metropolitan areas</p></li><li><p>Factors that make things worsecalm conditionslow level emission sourcestemperature inversionshigh buildings and narrow streets</p></li><li><p>The POEO ActThis act specifies all legal requirements for the control of air pollution in NSW.The current regulation pertaining to air pollution control (in NSW) is called the;Protection of the Environment Operations (Clean Air) Regulation 2002 </p></li></ul>