Global Atmosphere Assignment
Due Date: 29th April 2011
Name: Slavica Kandic
ID: s3185267 Station: Museum
Data is supplied for an EPA monitoring station, showing changes in levels of monitored pollutants during a day. You can get a copy of the data for your assigned station from s:\ug\ENVI1011 or the learning hub site for ENVI 1011.
a) Describe the location and characteristics of the station b) Display the data on a suitable graph to show the relative changes in each pollutant during the day c) For each pollutant monitored, indicate whether it is a primary or secondary pollutant and briefly describe the method of analysis and health effects. d) Which smog model is appropriate for this data? Explain why each pollutant changes the way it does during the day and how this fits the model. e) Which single pollutant best indicates the extent of air pollution? f) For each pollutant, tabulate (i) the maximum 1 hour level and (ii) the maximum 8-hour average. Do either exceed acceptable or detrimental levels? Would a day of significant smog be declared?
a) Richmond Air Monitoring Station is located on the roof of the Child Care Centre at Lord Street, within residential and light industrial area, on the sampling point of 4 meters. A station is positioned 29m from Lord Street and 30 m from Duke Street. This monitoring site operates as RDAS site from 2nd of October 2000. Monitoring has begun on 3rd of January 1983. Pollutants monitored are Carbon Monoxide (CO) and Nitrogen Dioxide (NO2), while Ozone (O3), Hydrocarbons (HC) and particles are not monitored on this station. (EPA,2011)
Fig.1 Relative changes in concentration of monitored pollutants over a 24 hour period
c)Carbon Monoxide (CO) is primary pollutant as it is formed from incomplete combustion of fossil fuel and mostly emmited from the motor vehicles into the atmosphere. Carbon monoxide is harmful for both humans and animals because it penetrates through the membrane of the lung tissue,where it binds with haemoglobins which transfer an oxygen to the cells. This process reduces transporting ability of the blood to supply tissues and cells with oxygen which may cause heart disfunction because the strain to preserve the needed level of oxygen in the body. Detection of CO is made up by Gas Filter Correlation Method which is basicly comparision of the gases in the analyzed sample and absorption of the infra-red spectrum of reference gas being measured.(EPA)
Ozone (O3) i a secondary pollutant and major component of the photochemical smog.It is not emmited directly from the source,and is formed by chemical reaction which acts in atmosphere.In the presence of sunlight as a most important contributor,ozone is formed in seres of reactions involving hydrocarbons and NO2. As highly reactive oxidant,ozone can cause irritation to the eyes resulting in watering and itching. Furthermore,it can lead to the nose irritation causing reduced ability to detect odor, to affect the lower bronchial airways. Bronchitis,astma and hay fever patiences may experience breathing problems. Fortunately,ozone is highly reactive and consequently has no cummulative effect. Ozone is detected by gas phase Chemiluminescence. In this method, a stabile ethylene flow is mixed with the sample in areaction chamber,where reaction among ethylene and ozone occur emmiting light of specific wavelenght.The light released is chopped while photomultiplier tube which is sensitive on light sended as a signal for output.(EPA)
Nitric Oxide (NO) reffer to primary pollutant as origiates from natural sources such as marine ecosystems, soil,but mostly initiates from human activities such as industry and motor vehicle emission. These activities release heat which oxidise elementary...