Influence of meteorological factors on air pollution concentration for a coastal region in India

A long-term study of measurement of concentration of NO_x, SO₂ and TSP pollutants have been done in a port and harbour region in India. Monthly measurements of gaseous and particulate pollutants were made at six monitoring stations from January 1997 to December 2000. Meteorological data was also simultaneously collected. In this study, the relationship between monitored ambient air quality data and meteorological factors, such as wind speed, temperature, is statistically analysed, using the SPSS package. The monthly mean concentrations of NO_x, SO₂ and TSP were in the range of 19.5–59.0 μg/m3, 8.6–51.3 μg/m3 and 88.2–199.3 μg/m3, respectively. The results show that TSP is strongly correlated with NO_x and SO₂ with a correlation coefficient of 0.83 and 0.82, respectively. The correlation coefficients for TSP, NO_x, and SO₂ with wind are –0.78, –0.78, and –0.88, respectively.     

A structural decomposition analysis of air pollution from fossil fuel combustion in India

During the last decade, there has been worldwide concern with global climate change, which has been induced by greenhouse gases (GHGs) due to the use of fossil fuels. The CO₂ emissions from fossil fuel combustion have been identified as the single most significant source of GHG emissions into the atmosphere. Realising the need to control and regulate emissions of pollutants, the objective of the present study estimates the trend of CO₂, SO₂ and NO_x between the periods 1991-92 and 1996-97. An input-output structural decomposition analysis approach is used to determine their sources of change. It also provides a set of alternative scenarios for the year 2001-2 and 2006-7. The sources of changes in the amount of CO₂, SO₂ and NO_x emissions are categorised into four factors: the ecoefficiency, the structure of production, the structure of demand, and the volume of demand. Results indicate that the electricity sector contributes more towards direct, as well as indirect, emission coefficients. The petroleum product sector also contributes more in this respect. The dominant role is played by the structure of demand and the volume of demand.     

Air pollution and the influence of sources on Paulinia (Brazil) and surroundings

The air quality in the industrial area and surroundings of the city of Paulinia (state of Sao Paulo, Brazil) has been investigated by analysing the concentration of air pollutants (SO₂, PM₁₀, NO, NO₂, CO and ozone) and identifying the main sources of air pollution. A mobile pollutant monitoring unit was used to collect the data at five different sites from November 2000 to July 2002. Critical pollutants were determined based on air quality standards, and sources were identified by principal component analysis. Photochemical reactions play an important role in Paulinia's air pollution: three out of five monitored sites showed levels exceeding the standard air quality of ozone. SO₂ and PM₁₀ appeared as pollutants deserving special attention. All the monitored sites showed vehicles and industrial plants (which release SO₂) to be significant sources of pollution. Depending on the location, ozone was related mainly with vehicular or industrial sources.     

Measurement of atmospheric particles and anionic species across central Taiwan

The ambient air concentrations and fluxes of various anionic species were sampled by MOUDI, TSP and dry deposition plates at a traffic sampling site in Taichung, central Taiwan. In the sampling period, from September to December 2000, the ambient air particle concentrations (PM₁, PM_2.5, PM₁₀ and TSP) were lower in the September than in the other three months (October to December). The reason is that the northwest wind brought more particles (diameter less than 10 μm) and the higher wind speed caused higher dry deposition fluxes and TSP concentrations in the last three months. The anion species percentages of TSP were 0.24%, 13.7%, 0.52%, 12.0%, 18.9'% and 54.6% for F^-, Cl^-, Br^-, NO₂^-, NO₃^- and SO₄^2-, respectively. The results revealed that SO₄^2-, NO₃^-, Cl^- and NO₂^- were the dominant species at the traffic sampling site. The ion-size distributions of Cl^-, NO₂^- and NO₃^- were unimodal, the main peak being between 3.2 and 5.6 μm. In contrast, the size distribution of SO₄^2- was bimodal, with the main peaks in the particle size ranges 0.32.0.56 μm and 3.2.5.6 μm. The ambient average particle dry deposition flux was 6.28 μg/m2/s, and the dry deposition fluxes were 0.01, 94.6, 0.05, 34.7, 72.2 and 376.4 ng/m2/s for F^-, Cl^-, Br^-, NO₂^-, NO₃^- and SO₄^2-, respectively. The dry deposition velocities were 3.10, 0.03, 3.67, 0.05, 1.54, 2.03 and 3.67 cm/s for F^-, Cl^-, Br^-, NO₂^-, NO₃^- and SO₄^2-, respectively.     

Limited provision of roads as a bottleneck on vehicle CO2 emissions in Asia: an international comparison of national trends

This paper explores the relationship between road infrastructure, economic growth and road CO₂ emissions. The basic premise is that many developing nations have achieved sufficient wealth to generate substantial demand for road vehicles, but that actual use is constrained by limited provision of surfaced roads. Our main result is that for comparable levels of income (GDP/capita), CO₂ emissions per length of paved road are far higher in rapidly developing Asia as compared to the USA. These findings suggest existence of an 'infrastructure bottleneck', that when relieved, may influence the future trajectory of road transport CO₂ emissions in developing Asia.     

Exploratory study of some potential environmental impacts of CO2 sequestration in unmineable coal seams

An initial investigation into the potential environmental impacts of CO₂ sequestration in unmineable coal seams has been conducted, focusing on changes in the produced water during enhanced coalbed methane (ECBM) production, using a CO₂ injection process (CO₂-ECBM). A high volatile bituminous coal, Pittsburgh No. 8, was reacted with synthetic produced water and gaseous carbon dioxide at 40°C and 50 bar to evaluate the potential for mobilisation of toxic metals during CO₂-ECBM/sequestration. Microscopic and X-ray diffraction analysis of the post-reaction coal samples clearly show evidence of chemical reaction and chemical analysis of the synthetic produced water shows substantial changes in composition. These results suggest that changes to the produced water chemistry and the potential for mobilising toxic trace elements from coal beds are important factors to be considered when evaluating deep, unmineable coal seams for CO₂ sequestration.     

Air pollution at the Bily Kriz mountains in the Czech Republic

An evaluation of air pollution at the Bily Kriz mountains in the Czech Republic is given. Annual daily concentrations of sulphur dioxide (SO₂), nitrogen oxides (NO_x), particulate matter of size 10 mm (PM₁₀) and ozone (O₃) measured in the years 1994–2000 are presented. Air pollution at Bily Kriz is assessed with the reference to the European Union Directives and the standards adopted by the Czech Republic. In general, the concentrations of air pollutants were lower in 1996 for ozone and decreased for SO₂, NO_x and PM₁₀ from 1994. The daily values of SO₂ and PM₁₀ exceeded the European Union limits in approximately 0.0% and 5.5% of cases, respectively. The values of ozone exceeded the limits for the considered period.     

Changing consumption patterns and CO2 reduction

Today, most countries are facing national CO₂ targets focused on production and direct energy use. However, two important driving forces are increased consumption and changing consumption patterns. In this paper, we analyse the impact from household consumption on CO₂ emissions. Household energy use is taken into account, as is the consumption of commodities and services produced by industry. Based on Danish data, we estimate the CO₂ impact from different commodities. Further, we analyse the impact of changes in commodity mix in Danish household consumption in the period from 1966 to 1992. The results show that the change in commodity mix has been insufficient to compensate for the overall growth in Danish consumption. Further, we see that the consumption of food is a main contributor to overall Danish CO₂ emissions.     

The application of the RAINS model for Greece

In order to comply in 2010 with the emission ceilings proposed by European commission under the convention on transboundary air pollution, Greece has to develop and implement a cohesive strategy affecting all the sectors of the economy. The RAINS model was used for the evaluation of the environmental and economic impacts arising from the use of a number of control technologies under alternative energy scenarios. To this purpose a number of modifications regarding the input databases of RAINS were made. The analysis clearly reveals that the reduction of SO₂ emissions can be achieved in a lower cost compared to the reduction of NO_x emissions. Moreover, the complementarity of CO₂ abatement policies and the SO₂/NO_x abatement policies is also accented.     

Separate determination of PM10 emission factors of road traffic for tailpipe emissions and emissions from abrasion and resuspension processes

Little is known about the relevance of mechanically produced particles of road traffic from abrasion and resuspension processes in relation to the exhaust pipe particles. In this paper, emission factors of PM₁₀ and PM₁ for light and heavy-duty vehicles were derived for different representative traffic regimes from concentration differences of particles and nitrogen oxides (NO_x) in ambient air upwind and downwind of busy roads, or alternatively of kerbsides and nearby background sites. Hereby, PM₁ was interpreted as direct exhaust emissions and PM₁₀-PM₁ as mechanically produced emissions from abrasion and resuspension processes. The results show that abrasion and resuspension processes represent a significant part of the total primary PM₁₀ emissions of road traffic. At sites with relatively undisturbed traffic flow they are in the same range as the exhaust pipe emissions. At sites with disturbed traffic flow due to traffic lights, emissions from abrasion/resuspension are even higher than those from the exhaust pipes.     

Analysis and interpretation of the monitoring data for C2–C11 hydrocarbons in the atmosphere of a rural Portuguese site

This paper focuses the application of a measurement technique for determining atmospheric C₂–C₆ hydrocarbons after canister sampling and analysis by gas chromatography/flame ionisation detection (GC/FID), as well of an adsorption-sampling technique for C₆–C₁₁ compounds and GC/FID analysis after thermal desorption and cryogenic concentration. Tens of samples collected at Giesta, a rural area located 20 km to the SE of the coastal Portuguese city of Aveiro, were analysed. The characterisation of C₂ C₁₁ hydrocarbons is presented, considering seasonal variations, diurnal cycles, the influence of air masses and different photochemical conditions. Ratios between hydrocarbons and principal components analysis were applied to differentiate between biogenic and anthropogenic sources.     

Preparation, characterisation and testing of photocatalytic polymeric membranes with entrapped or suspended TiO2

Various cellulose triacetate (CTA) or polysulfone (PSf) membranes with entrapped polycrystalline TiO₂ were prepared by using different methods of the so-called phase inversion process. Porosity and permeability of the membranes increased by increasing the amount of entrapped TiO₂ while rejection decreased. The photoactivity of entrapped TiO₂ for the degradation of congo-red was compared with that of the same quantity of suspended TiO₂ and the results indicated that TiO₂ was always more efficient when used in suspension. A hybrid configuration consisting of a continuous membrane photoreactor with the photocatalyst in suspension showed to be the most promising one.     

Sampling errors in the study of acid gases and anion species in atmospheric aerosols

Atmospheric acid aerosols were sampled by two annular denuder systems (ADS) and a micro-orifice uniform deposit impactor (MOUDI) at a traffic site in central Taiwan. Theoretical analysis showed that the relative artifact for HNO₃ gas sampling was about 0.53 when the initial HNO₃ concentration was under 0.2 µg/m³ and should be considered carefully. The concentrations of gaseous acid at the traffic sampling site were higher than those in the other study. The size distributions of acid aerosols were unimodal for Cl^-, NO₂^-, and NO₃^-, and bimodal for SO₄^2-. The dominant acid ions in particles less than 18 µm were SO₄^2-, NO₃^-, NO₂^- and Cl^-.     

Spatial and diurnal variations in concentration of atmospheric NOx along urban-rural roadways in Nanjing, Southeastern China

Atmospheric NO_x concentrations (including NO₂ and NO) on the roadside environments of urban trunk, belt highway and suburban road as well as a reference in a forest area were measured. NO_x concentrations on roadside environments tended to be higher than that on the reference. With the exception of suburban road, NO_x concentrations over both of the urban trunk and belt highway exceeded the limited value of National Air Environmental Quality Standards. Gradient measurement of NO_x on the downwind side of the belt highway shows that it declined to background level over 100 m from the road edge.     

Air pollution and inversion features in Istanbul

Air pollution in the Istanbul metropolitan area arises from three significant sources: industrial and residential fossil fuels and road traffic. In winter this combination pushes air pollution to levels that are dangerous to humans and to plant life. As far as fossil fuels are concerned, total suspended particulates (TSP) and sulphur dioxide are the chief pollutants. In order to investigate the problem, five-year winter-season monthly pollution concentration records are used, starting from 1989. Classical statistical methods, such as frequency distribution functions, are examined and found to have exponential (SO₂), logarithmic normal (TSP) and Weibull (inversion height) distributions. A simple concept of 'pollutant polygon' is presented in order to make detailed interpretations of the relationship between the monthly averages of SO₂ and TSP. These levels were affected by the weak dispersion conditions in the lower atmosphere over the city.     

A statistical model for predicting carbon monoxide levels

This paper presents a statistical model that is able to predict carbon monoxide (CO) concentrations as a function of meteorological conditions and various air quality parameters. The experimental work was conducted in an urban atmosphere, where the emissions from cars are prevalent. A mobile air pollution monitoring laboratory was used to collect data, which were divided into two groups: a development group and a testing group. Only the development dataset was used for developing the model. The model was determined by using a stepwise multiple regression modelling procedure. Thirteen independent variables were selected as inputs: non-methane hydrocarbon (NMHC), methane (CH₄), suspended dust, carbon dioxide (CO₂), nitrogen oxide (NO), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), ozone (O₃), wind speed, wind direction, temperature, relative humidity and solar energy. It was found that NO has the most effect on the predicted CO concentration. The contribution of NO to the CO concentration variations was 91.3%. Adding in the terms for NO₂), NMHC and CH₄ improved the model by only a further 2.3%. The derived model was shown to be statistically significant, and model predictions and experimental observations were shown to be consistent.     

Roadside particulate levels at 30 locations in the Kathmandu Valley, Nepal

Roadside particulate levels (PM₁₀) at 30 locations throughout the Kathmandu Valley, Nepal are reported. There were seven sampling cycles from January to December 1999. PM₁₀ levels ranged between 1000 and 6000 μ/m3 for 1-h sampling. There was no consistent trend in PM10 levels with respect to monitoring cycle, average precipitation or wind speed. There is no WHO guideline for PM₁₀ (no safe exposure threshold), but the EPA 24-h standard is 150 μ/m3. The major sources of roadside PM₁₀ include dust re-suspension from vehicular movement and human activity, and particulate emissions from old vehicles. Other sources of PM₁₀ in the valley include cement and brick factories. Studies are currently being conducted to determine the lead content of PM₁₀ from roadside samples. Additional studies are warranted to assess the potential adverse human health effects of acute or chronic exposure to high particulate levels reported in this study.     

Diurnal and seasonal variations of carbon monoxide and nitrogen dioxide in Delhi city

Motor vehicle exhaust emissions are one of the major causes of air quality deterioration in most of the cities of the developing world. Carbon monoxide (CO) and nitrogen dioxide (NO₂) are significant contributors to this adverse effect on the environment. This study analyses air quality data for three years from 1997 to 1999, at two air quality control regions in Delhi city. The regions are a major traffic intersection and the moderately busy straight Khelgaon Marg road. The data were obtained from the Central Pollution Control Board (CPCB), Delhi. The results show that the highest ground-level concentrations of CO and NO₂ occurred during winter (November to March) and the lowest during the tropical monsoon period (July to September) at both regions. Typical average monthly, weekly and diurnal cycles of CO at both regions have also been analysed, and show that CO concentrations are higher at the intersection than along the road. Further, the monthly average NO₂ concentrations were also found to be higher at the intersection.     

Effect of leachate recirculation on refuse decomposition rates at landfill site: a case study

In this study, a comparison of methane (CH₄) generation rates for two test cells, one operated with (enhanced) and another without leachate recirculation at Odayeri Sanitary Landfill were compared using their bio-chemical methane potentials (BMP). Initial methane potential is approximately 34.5 m3 CH₄/wet ton of solid waste. The remaining methane potential for the control (C1) and the enhanced (C2) cells are 32.6 m3 CH₄/wet ton and 31.1 m3 CH₄/wet ton of refuse after eight months of operation, respectively. The produced CH₄ quantities for C1 and C2 after eight months of operation are 1.9 m3 CH₄/wet ton and 3.4 m3 CH₄/wet ton, respectively. On the other hand, 5.5% and 9.9% of the total potential are generated in eight months. However, the CH₄ generation rates for the first year are determined as 2.85 and 5.10 m3/ton/year for C1 and C2 test cells, respectively. Due to the appropriate conditions such as moisture content, solid waste decomposition rate is enhanced at a rate of 79% at C2 test cell relative to C1 test cell. Hence, C2 test cell shows more decomposition relative to the C1 test cell.     

Sensitivity analysis of the CERES-wheat model for variations in CO2 and meteorological factors in Northwest Turkey

Plant growth is very sensitive to variations in atmospheric factors. Possible effects of climate change on plant growth can be estimated and evaluated using the crop growth simulation models. In this study, the CERES (Crop Environment Resource Synthesis)-wheat model was applied to two consequent growing seasons (1997–1998 and 1998–1999) in order to determine the model sensitivity on the changes in several meteorological factors such as air temperature, precipitation, solar radiation and carbon dioxide (CO₂) concentration. In the model, the air temperature variations were applied from ±1°C up to ±2°C and CO₂ were changed in the range of 20% to 100%, while the solar radiation, precipitation were varied between 10% and 20%. Biomass and the grain yield of the wheat crop were influenced positively by the increased combination of the solar radiation, air temperature and CO₂. However, low crop responses to the variations in precipitation were unexpected.