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Abstract Using waste paper as fuel for domestic heating is a beneficial recycling option for small island developing states where there are lacks of resources for energy and waste treatment. However, there are concerns about the impact of air pollutants emitted from the burning of the self-made paper briquettes as household air pollution is recognised as the greatest environmental risk for human. In this study, combustion tests were carried out for paper briquettes made in one Pacific island and three commercial fuels in Australia including wood briquettes, kindling firewood and coal briquettes in order to: 1) characterise the emissions of three criteria air pollutants including particulate matters, CO and NO x including their emission factors (EF) from the tested fuels; and 2) compare the EFs among the tested fuels and with others reported in the literature. The results showed that waste paper briquettes burned quickly and generated high temperature but the heat value is relatively low. Paper briquettes and coal briquettes produced higher CO concentration than the others while paper briquettes generated the highest NO x level. Only PM 2.5 concentration emitted from paper briquettes was similar to kindling firewood and lower than wood briquettes. Burning of paper briquettes and wood briquettes produced particulate matter with large average count median diameter (72 and 68 nm) than coal briquette and kindling firewood (45 and 51 nm). The EFs for CO, NO x and PM 2.5 of paper briquettes were within the range of EFs reported in this study as well as in the literature. Overall, the results suggested that using paper briquettes as fuel for domestic heating will not likely to generate higher level of three major air pollutants compared to other traditional fuels. Highlights • The first attempt to report emission of key air pollutants from waste paper briquettes. • Burning of paper briquettes emitted relatively high CO and NO x concentration. • Burning of paper briquettes emitted PM with large average particle size. • Waste paper could be recycled as briquettes for domestic use like other common fuels. [ABSTRACT FROM AUTHOR]

This study characterizes the combustion of paper and sewage sludge in a pilot-scale fluidized bed. The highest temperature during combustion within the system was found at the surface of the fluidized bed. Paper sludge containing roughly 59.8% water was burned without auxiliary fuel, but auxiliary fuel was required to incinerate the sewage sludge, which contained about 79.3% water. The stability of operation was monitored based on the average pressure and the standard deviation of pressure fluctuations. The average pressure at the surface of the fluidized bed decreased as the sludge feed rate increased. However, the standard deviation of pressure fluctuations increased as the sludge feed rate increased. Finally, carbon monoxide (CO) emissions decreased as oxygen content increased in the flue gas, and nitrogen oxide (NOx) emissions were also tied with oxygen content. [ABSTRACT FROM AUTHOR]

This paper reanalyzes the determinants of the CO emissions in France. For this purpose, it considers the unit root test with two structural breaks and a dynamic ordinary least squares estimation. The paper also considers the effects of the energy consumption and the economic complexity on CO emissions. First, it is observed that the EKC hypothesis is valid in France. Second, the positive effect of the energy consumption on CO emissions is obtained. Third, it is observed that a higher economic complexity suppresses the level of CO emissions in the long run. The findings imply noteworthy environmental policy implications to decrease the level of CO emissions in France. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study of carbon monoxide (CO) formation and emissions in both grate drying bed incinerators and circulating fluidized bed (CFB) incinerators to simulate the two key parts of a combined grate and circulating fluidized bed (grate-CFB) incinerator in order to investigate pollutant emission control in municipal solid waste (MSW) combustion that occurs in a grate-CFB incinerator utilizing a patented technology. Polyvinyl chloride, polystyrene, kitchen waste, paper, textile, etc. were chosen to simulate the MSW. The effects of temperature, air staging, and moisture on the CO formation and emissions were analysed for both the grate drying bed combustion and the CFB combustion. In the grate drying bed, the low temperatures increased the carbon to CO conversion rate which also increased slightly with the moisture content. Industrial field tests in a commercial grate-CFB incinerator showed that the CO concentration at the grate drying bed exit was very high and decreased along furnace height. The carbon to CO conversion rates were 0-20% for the grate drying bed which exceeded the range of 0.8-16% measured in a grate drying bed exit of the commercial grate-CFB incinerator tests. In the commercial grate-CFB incinerator tests, at excess air ratios ranging from 1.5-2.0 or more, the CO emissions decreased to a low and stable level, whose corresponding carbon to CO conversion rates were far lower than 0-10%. The low CO emission is one of the factors enabling the polychlorinated dibenzodioxin/polychlorinated dibenzofuran emissions to satisfy the Chinese national regulations. [ABSTRACT FROM AUTHOR]

The processes that cause changes to the natural characteristics of the air have a strong dynamic; this being a reason why the environmental study must have sufficient quantitive and qualitative data, in order to meet the appropriate requirements of the spatial and temporal representation. This paper deals with issues of the air quality management in the Olt County, for the pollution indicator - carbon monoxide (CO). The paper presents the main features of this pollutant, the emission sources and the monitoring for 2014, the year with the lowest emission of CO, for the period 2008 - 2014, in terms of the annual, monthly and daily average concentrations, in relation to the causes that diminish or emphasize the values. In the end of the paper, the authors present the conclusions based on the data interpretations, provided after the monitoring of the pollution indicator - CO. [ABSTRACT FROM AUTHOR]

Modern indoor air quality (IAQ) management plans integrate the use of valid air quality models that accurately predict the dynamics of air quality variations within a considered environment. With rapid advancements in the field of computer sciences that helped improve the capabilities of computational resources and the availability of a wide-ranging spectrum of methodologies that address different aspects of the nonlinearity in a multi-dimensional information domain, there is ample scope for environmental professionals to develop and use hybrid IAQ models. This software review paper presents one such methodology that combines the use of the univariate time series and the radial basis function neural network methods in the development and evaluation of univariate time series based radial basis function neural network hybrid IAQ models for the monitored contaminants of carbon dioxide and carbon monoxide inside a public transportation bus using available software. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 320-324, 2016 [ABSTRACT FROM AUTHOR]

In order to make Mars a better planet, in this paper, photo-dissociation technology, mathematical modeling, and a series of chemical reaction methodology have been proposed to create a vibrant ecosystem and balance the atmosphere on Mars. Since CO is a stable compound, breaking it down into C and O always is challenging, but exciting thought. Interestingly, my recent research revealed that photo-dissociation by utilizing UVV (laser) could be an exciting technology to split CO into C + O since the theoretical reaction suggested that the production of C + O channel from CO photo-exciting technology releases the energetic level threshold of C(P) + O(X∑) that can be detected by ultraviolet laser pump-probe spectroscopy. Subsequently, a mathematical model for creating of ocean on Mars by breaking its substantial polar ice has been performed considering algorithms for surface and coordinate between the barotropic momentum and continuity equations, and interestingly the calculation suggested that it is very much possible to flow ocean on Mars surface to meet its water demand. Subsequently, proposed series of chemical reaction technology suggested that implementation of carbonator looping and plasma reaction paths can convert photo- dissociated carbon (C) into N and NH to enrich Mars' soil in order to grow vegetation as well as to create a balance ecosystem in Mars eventually. Finally, sustainable green technology has been proposed for the development of Mars to be a complete balanced planet to deliver all basic and modern needs to run daily life smoothly. Thus, implication of chemical reaction technologies along with sustainable development plans can indeed make the Mars a vibrant environment to live there in clean and green. [ABSTRACT FROM AUTHOR]

Nowadays, BRICS (i.e., Brazil, Russia, India, China, and South Africa) becomes more and more important in the world in terms of not only economic development, but also energy consumption. The purpose of this paper is to study occurrence of a decoupling between economic growth and energy-related CO emission in BRICS countries from 1995 to 2014. Furthermore, the LMDI theory is utilized to find the decoupling reasons. The main conclusions drawn from the present study may be summarized as follows: (1) During the study period, China was the largest CO emitter among BRICS countries; per capita energy-related CO emission in Russia was the largest in BRICS countries. (2) The share of fossil energy to total energy consumption for South Africa accounted for more than 96 %. However, the share of fossil energy to total energy consumption for Brazil accounted for about 60 % over the study period. (3) For Brazil, Russia, and South Africa, five decoupling status occurred during the study period. However, only three decoupling status occurred in China and India. (4) The energy intensity effect played a positive role in decreasing CO emission in all five BRICS countries. [ABSTRACT FROM AUTHOR]

This paper shows that a split-fuel-injection strategy can achieve robust, near-zero smoke and nitrogen oxide emissions at reduced exhaust gas recirculation levels under low-temperature combustion conditions. The overall objective of the work was to investigate the sensitivity (in terms of the engine emissions and the fuel economy) of a 50:50 (by mass) split-injection strategy to variations in the key engine operating parameters. Experiments were performed at operating conditions corresponding to a gross indicated mean effective pressure of 500 kPa at an engine speed of 1500 r/min in a 0.51 l single-cylinder high-speed direct-injection diesel engine. The paper presents the effects of different relative fuel injection timings at a variable intake oxygen mass fraction (10.5% and 12%) at a constant intake pressure (120 kPa, absolute) on the smoke, total hydrocarbon and carbon monoxide emissions with the split-main-injection strategy. The effects of a variable fuel injection pressure (90 MPa and 110 MPa) on diesel low-temperature combustion with split injection are also reported, as are the effect of an increased intake pressure (150 kPa, absolute). The combined effects of the operating parameters and the fuel injection timing on the smoke, nitrogen oxide, total hydrocarbon and carbon monoxide emissions and the gross indicated specific fuel consumption are described. For selected operating conditions, the cycle-resolved spray and combustion processes are visualized together with the flame temperature measurement using two-colour optical pyrometry to understand the combustion phenomena occurring in the split-injection strategy. The results of the optical studies show that different low-temperature combustion operating conditions producing similarly low levels of ‘engine-out’ smoke emissions have substantially different histories of soot formation and soot oxidation. An increase in the intake oxygen mass fraction reduced the total hydrocarbon emissions and the gross indicated specific fuel consumption at a given intake pressure, while a higher intake pressure reduced them further. Although significant soot formation took place from the second injection event, the majority of the soot was subsequently oxidized because of a slightly higher flame temperature and slightly higher oxygen concentration than in single-injection high-exhaust-gas-recirculation low-temperature combustion. A higher injection pressure did not have any significant effect on the emissions and the gross indicated specific fuel consumption. [ABSTRACT FROM AUTHOR]

One of the most pressing policy challenges facing the world today concerns how to mitigate global warming while improving people's well-being. The green paradox argues that increasing taxes on CO emissions exacerbates global warming in the present because firms have the incentive to bring forward the extraction and sale of fossil fuels. This paper shows that whenever technological progress allows the extraction costs of fossil fuels to be reduced over time and a positive R&D subsidy is paid, a growing tax on CO emissions reveals a welfare maximizing policy. [ABSTRACT FROM AUTHOR]

With the growing demand, China's iron and steel industry has obtained rapid development since the 1990s. China's steel output reached 220 million tons for the first time in 2003, becoming the first country whose annual production exceeded 200 million tons. The iron and steel is an industry of high energy consumption, high pollution and high emissions which has attracted deep concern of Chinese government. Previous research has estimated the direct CO emissions in individual processes of iron and steel production, while research on the indirect CO emissions from the related sectors of the iron and steel industry is scarce. To explore the whole CO emissions, this paper evaluates the direct and indirect carbon emissions in the iron and steel industry and carbon emission deduction by building an economic input-output life cycle assessment (EIO-LCA) model based on the latest available data of the input-output extension table in 2010 and China's Energy Statistical Yearbook in 2011. The results show that coke and coal produce the most direct CO emissions and raw chemical materials, medical and chemical fiber manufacturing, transportation storage and the postal industry, the electricity heat production and supply industry, nonmetal mineral production, petroleum processing of coke and nuclear fuel processing, coal mining and dressing are the six sectors that produce the largest indirect CO emissions among the 35 sectors in the iron and steel industry. Based on the results, we suggest that China should (1) improve the quality of coke and coal, increase the efficiency of coke and coal, coal blending technology and the cokes' strength, and employ the scrap or cities' minerals as main raw materials in the production, and at the same time, the government and enterprises may increase to invest in technology innovation; (2) and use high-strength iron and steel instead of the ordinary one. Meanwhile, the spatial distributions of the six sectors are mainly concentrated in Shandong Province, Jiangsu Province, Zhejiang Province and Shanxi Province. Shandong Province, Jiangsu Province, Zhejiang Province and Shanxi Province may adjust their industrial structure by increasing the proportion of the third industry and accelerating the development of high-tech industries and services. [ABSTRACT FROM AUTHOR]

Understanding the causal relationships among economic growth, energy consumption, and CO emission is important for formulating energy conservation and emission reduction policies. In this paper, we explore the causal relationships among economic growth, energy consumption, and CO emission in China during 1978-2012 by using both the linear and nonlinear causality tests. The obtained results show that the links examined by the linear and nonlinear causality tests are not all same. Both linear and nonlinear causality tests indicate a unidirectional causality from CO emission to GDP and a bi-directional causality between energy consumption and CO emission. Linear causality test indicates a unidirectional causality from energy consumption to GDP, while nonlinear causality test indicates a unidirectional causality from GDP to energy consumption. Finally, policy recommendations are proposed for achieving the target of coordinated, sustainable development of China. [ABSTRACT FROM AUTHOR]

China has a large number of rural-urban migrant workers in the 'semi-urban' states, and their consumption pattern differs from that of rural residents and urban residents. To ensure that society develops sustainably and stably, it is necessary to be concerned about the issues of migrant workers. Based on the data gathered and processed, this paper focuses on the impacts of the consumption of China's migrant workers on energy use and CO emissions using the input-output method. The results show that: the living conditions, health care and allocation of educational resources have not been effectively ensured for migrant workers. The total CO emission per capita of migrant workers is relatively low, at two-thirds of the national average and less than one-third that of urban residents. Marginal energy consumption and marginal carbon emission coefficients of migrant workers are slightly lower than the national average level, at 4.9 tce (tonne of standard coal equivalent) per million yuan and 11.6 t CO per million yuan lower than those of urban residents. The sectors of food manufacture, and production and distribution of electricity make the greatest contributions to the total carbon emissions of migrant workers, at up to 36.3 %. The citizenization of migrant workers will lead to an increase of 272 million tons of CO emissions of primary energy, and the top ten sectors, led by the sectors of electricity production and distribution, and health, will produce more than 60 % of the total increase in carbon emissions. With the acceleration of urbanization and citizenization, the total carbon emissions embodied in the consumption of migrant workers are likely to rise. Further efforts are required to control and reduce the indirect carbon emission, such as by improving energy price mechanism and optimization of the power structure. [ABSTRACT FROM AUTHOR]

Biomass burning is a significant source of trace gases and aerosols to the atmosphere, and the evolution of these species depends acutely on where they are injected into the atmosphere. GEOS-Chem is a chemical transport model driven by assimilated meteorological data that is used to probe a variety of scientific questions related to atmospheric composition, including the role of biomass burning. This paper presents the development and implementation of a new global biomass burning emissions injection scheme in the GEOS-Chem model. The new injection scheme is based on monthly gridded Multi-angle Imaging SpectroRadiometer (MISR) global plume-height stereoscopic observations in 2008. To provide specific examples of the impact of the model updates, we compare the output from simulations with and without the new MISR-based injection height scheme to several sets of observations from regions with active fires. Our comparisons with Arctic Research on the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) aircraft observations show that the updated injection height scheme can improve the ability of the model to simulate the vertical distribution of peroxyacetyl nitrate (PAN) and carbon monoxide (CO) over North American boreal regions in summer. We also compare a simulation for October 2010 and 2011 to vertical profiles of CO over the Amazon Basin. When coupled with larger emission factors for CO, a simulation that includes the new injection scheme also better matches selected observations in this region. Finally, the improved injection height improves the simulation of monthly mean surface CO over California during July 2008, a period with large fires. [ABSTRACT FROM AUTHOR]

This paper applies the probabilistic approach developed by Daraio and Simar (J Prod Anal 24:93-121, , Advanced robust and nonparametric methods in efficiency analysis. Springer Science, New York, , J Prod Anal 28:13-32, ) in order to develop conditional and unconditional data envelopment analysis (DEA) models for the measurement of countries' environmental efficiency levels for a sample of 110 countries in 2007. In order to capture the effect of countries compliance with the Kyoto protocol agreement (KPA) policies, we condition first the years since a country has signed the KPA until 2007 and secondly the obliged percentage level of countries' emission reductions. Particularly, various DEA models have been applied alongside with bootstrap techniques in order to determine the effect of KPA on countries' environmental efficiencies. The study illustrates how the recent developments in efficiency analysis and statistical inference can be applied when evaluating environmental performance issues. The results indicate a nonlinear relationship between countries' obliged percentage levels of emission reductions and their environmental efficiency levels. Finally, a similar nonlinear relationship is also recorded between the duration which a country has signed the KPA and its environmental efficiency levels. [ABSTRACT FROM AUTHOR]

Context. Long gamma-ray bursts (GRBs) can potentially be used as a tool to study star formation and recent gas accretion onto galaxies. However, the information about gas properties of GRB hosts is scarce. In particular, very few carbon monoxide (CO) line detections of individual GRB hosts have been reported. It has also been suggested that GRB hosts have lower molecular gas masses than expected from their star formation rates (SFRs). Aims. The objectives of this paper are to analyse molecular gas properties of the first substantial sample of GRB hosts and test whether they are deficient in molecular gas. Methods. We obtained CO(2-1) observations of seven GRB hosts with the APEX and IRAM 30 m telescopes. We analysed these data together with all other hosts with previous CO observations. From these observations we calculated the molecular gas masses of these galaxies and compared them with the expected values based on their SFRs and metallicities. Reults. We obtained detections for 3 GRB hosts (980425, 080207, and 111005A) and upper limits for the remaining 4 (031203, 060505, 060814, and 100316D). In our entire sample of 12 CO-observed GRB hosts, 3 are clearly deficient in molecular gas, even taking into account their metallicity (980425, 060814, and 080517). Four others are close to the best-fit line for other star-forming galaxies on the SFR-MH2 plot (051022, 060505, 080207, and 100316D). One host is clearly molecule rich (111005A). Finally, the data for 4 GRB hosts are not deep enough to judge whether they are molecule deficient (000418, 030329, 031203, and 090423). The median value of the molecular gas depletion time, MH2/SFR, of GRB hosts is ∼0.3 dex below that of other star-forming galaxies, but this result has low statistical significance. A Kolmogorov–Smirnov test performed on MH2/SFR shows an only ∼2σ difference between GRB hosts and other galaxies. This difference can partly be explained by metallicity effects, since the significance decreases to ∼1σ for MH2/SFR versus metallicity. Conclusions. We found that any molecular gas deficiency of GRB hosts has low statistical significance and that it can be attributed to their lower metallicities; and thus the sample of GRB hosts has molecular properties that are consistent with those of other galaxies, and they can be treated as representative star-forming galaxies. However, the molecular gas deficiency can be strong for GRB hosts if they exhibit higher excitations and/or a lower CO-to-H2 conversion factor than we assume, which would lead to lower molecular gas masses than we derive. Given the concentration of atomic gas recently found close to GRB and supernova sites, indicating recent gas inflow, our results about the weak molecular deficiency imply that such an inflow does not enhance the SFRs significantly, or that atomic gas converts efficiently into the molecular phase, which fuels star formation. Only if the analysis of a larger GRB host sample reveals molecular deficiency (especially close to the GRB position) would this support the hypothesis of star formation that is directly fuelled by atomic gas. [ABSTRACT FROM AUTHOR]

The paper presents the temporal variations of surface ozone (O) and its precursors (oxides of nitrogen (NO), carbon monoxide (CO), methane (CH) and non-methane hydrocarbons (NMHCs)) along with particulate matter (PM and PM) and their relationship with meteorology during January 2012 to December 2014 at an urban site of Delhi, India. The mean mixing ratio of surface O, NO, CO, CH and NMHCs were 29.5 ± 7.3 ppb, 34.7 ± 11.2 ppb, 1.82 ± 0.52 ppm, 3.07 ± 0.37 ppm and 0.53 ± 0.17 ppm, respectively. This study also comprises an analysis of the relation between UV irradiance and surface O. A relationship between the total oxidant concentrations (OX) and NO has been used to identify the regional background O values and the local levels of primary pollution. An attempt has been made to identify the existence of NO or NMHC sensitive regime by charting out relationships between O, NO and NMHCs. The respective high pollution periods of surface O and PM differ on a seasonal timescale. Linear regression analysis has been used to quantify the negative influence of the chemical constituents of PM (elemental carbon, NO , SO ) on O values. Statistical validation using bivariate correlation analysis, multiple linear regression (MLR) analysis and principal component analysis (PCA) strongly describes the intricate relationships among the aforesaid variables and meteorology. Potential Source Contribution Function (PSCF) and Concentration Weighted Trajectory (CWT) analysis indicated upper Indo-Gangetic Plain (IGP) as a significant source region of O precursor gases contributing for O values at the study site. [ABSTRACT FROM AUTHOR]

Purpose: Until recently, life cycle assessments (LCAs) have only addressed the direct greenhouse gas emissions along a process chain, but ignored the CO emissions of land-use. However, for agricultural products, these emissions can be substantial. Here, we present a new methodology for including the implications of land occupation for CO emissions to realistically reflect the consequences of consumers' decisions. Method: In principle, one can distinguish five different approaches of addressing the CO consequences of land occupation: (1) assuming constant land cover, (2) land-use change related to additional production of the product under consideration, (3) historic land-use change, assuming historical relations between existing area and area expansion (4) land-use change related to less production of the product under consideration ('missed potential carbon sink' of land occupation), and (5) an approach of integrating land conversion emissions and delayed uptake due to land occupation. Approach (4) is presented in this paper, using LCA data on land occupation, and carbon dynamics from the IMAGE model. Typically, if less production occurs, agricultural land will be abandoned, leading to a carbon sink when vegetation is regrowing. This carbon sink, which does not occur if the product would still be consumed, is thus attributed to the product as 'missed potential carbon sink', to reflect the CO implications of land occupations. Results: We analyze the missed potential carbon sink by relating land occupation data from LCA studies to the potential carbon sink as calculated by an Integrated Global Assessment Model and its process-based, spatially explicit carbon cycle model. Thereby, we account for regional differences, heterogeneity in land-use, and different time horizons. Example calculations for several livestock products show that the CO consequences of land occupation can be in the same order of magnitude as the other process related greenhouse gas emissions of the LCA, and depend largely on the production system. The highest CO implications of land occupation are calculated for beef and lamb, with beef production in Brazil having a missed potential carbon sink more than twice as high as the other GHG emissions. Conclusions: Given the significant contribution of land occupation to the total GHG balance of agricultural products, they need to be included in life cycle assessments in a realistic way. The new methodology presented here reflects the consequences of producing or not producing a certain commodity, and thereby it is suited to inform consumers fully about the consequences of their choices. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to investigate and quantify the impact of delivery restrictions on costs and environmental performance for a distribution operation. Design/methodology/approach – Data were gathered from a company and several scenarios with varying delivery restrictions were investigated. Findings – The results show significant reductions in cost and environmental impacts are achieved when restrictions are relaxed. However, the research also highlighted the importance of adopting a supply chain (SC) approach to the removal of restrictions and the need for public/private sector cooperation. Research limitations/implications – The case study is based on one company only. However, the company performs many trips each day to many different customers. Practical implications – The paper provides insight into the scope for change in the SC decision-making processes in order to reduce environmental impacts (and identifies limitations). Originality/value – The paper is a contribution to better understanding the importance of logistics decisions and not only transport when considering urban freight problems. [ABSTRACT FROM AUTHOR]

In the transition of socio-technical systems, local projects and experiments regarding the low carbon economy and climate mitigation/adaptation serve as transition places. In specific contexts, they become sites of innovation and creativity. This paper discusses and characterizes the innovative practices undertaken in local Danish arenas of transition, concentrating on technology and practice related to CO reductions within the housing and construction sector. In particular, the paper seeks to identify the various roles of local actors' deliberation in situated places of transition, thus contributing to the development of transition theories on actors and conditions for niche experimentation. Finally, the paper contributes to the building up of knowledge on transition dynamics related to low carbon construction and housing. Copyright © 2011 John Wiley & Sons, Ltd and ERP Environment. [ABSTRACT FROM AUTHOR]

Finding environmentally significant clusters in global supply-chain networks of goods and services has been investigated by Kagawa et al. (Soc Netw 35(3):423-438, 2013a; Econ Syst Res 25(3):265-286, 2013b; Glob Environ Chang, 2015), using the popular clustering method of nonnegative matrix factorization, which actually yields sensitive cluster assignments. Due to this sensitivity issue, there is a danger of overfitting of the results. In order to confirm the robustness of the obtained clusters, which in fact have strong implications for international climate change mitigation, especially for the US-induced Chinese clusters, we design a simulation-based experiment. Empirical findings of the proposed approach are compared with those of Kagawa et al. (Glob Environ Chang, 2015). The environmental implications are reported as well. [ABSTRACT FROM AUTHOR]

A new global reanalysis data set of atmospheric composition (AC) for the period 2003-2015 has been produced by the Copernicus Atmosphere Monitoring Service (CAMS). Satellite observations of total column (TC) carbon monoxide (CO) and aerosol optical depth (AOD), as well as several TC and profile observations of ozone, have been assimilated with the Integrated Forecasting System for Composition (C-IFS) of the European Centre for Medium-Range Weather Forecasting. Compared to the previous Monitoring Atmospheric Composition and Climate (MACC) reanalysis (MACCRA), the new CAMS interim reanalysis (CAMSiRA) is of a coarser horizontal resolution of about 110 km, compared to 80 km, but covers a longer period with the intent to be continued to present day. This paper compares CAMSiRA with MACCRA and a control run experiment (CR) without assimilation of AC retrievals. CAMSiRA has smaller biases than the CR with respect to independent observations of CO, AOD and stratospheric ozone. However, ozone at the surface could not be improved by the assimilation because of the strong impact of surface processes such as dry deposition and titration with nitrogen monoxide (NO), which were both unchanged by the assimilation. The assimilation of AOD led to a global reduction of sea salt and desert dust as well as an exaggerated increase in sulfate. Compared to MACCRA, CAMSiRA had smaller biases for AOD, surface CO and TC ozone as well as for upper stratospheric and tropospheric ozone. Finally, the temporal consistency of CAMSiRA was better than the one of MACCRA. This was achieved by using a revised emission data set as well as by applying careful selection and bias correction to the assimilated retrievals. CAMSiRA is therefore better suited than MACCRA for the study of interannual variability, as demonstrated for trends in surface CO. [ABSTRACT FROM AUTHOR]

Environmental concerns have been raised on the adverse health effects of vehicle emissions in micro-scale traffic-crowded street canyons, especially for pedestrians and residents living in near-road buildings. Viaduct design is sometimes used to improve transportation efficiency but possibly affects urban airflow and the resultant exposure risk, which have been rarely investigated so far. The personal intake fraction ( P _ IF ) is defined as the average fraction of total emissions that is inhaled by each person of a population (1 ppm = 1 × 10 −6 ), and the daily carbon monoxide (CO) pollutant exposure ( E t ) is estimated by multiplying the average concentration of a specific micro-environment within one day. As a novelty, by considering time activity patterns and breathing rates in various micro-environments for three age groups, this paper introduces IF and E t into computational fluid dynamic (CFD) simulation to quantify the impacts of street layouts (street width/building height W / H = 1, 1.5, 2), source location, viaduct settings and noise barriers on the source-exposure correlation when realistic CO sources are defined. Narrower streets experience larger P_ IF (1.51–5.21 ppm) and CO exposure, and leeward-side buildings always attain higher vehicular pollutant exposure than windward-side. Cases with a viaduct experience smaller P_IF (3.25–1.46 ppm) than cases without a viaduct ( P_IF = 5.21–2.23 ppm) if the single ground-level CO source is elevated onto the viaduct. With two CO sources (both ground-level and viaduct-level), daily CO exposure rises 2.80–3.33 times but P_IF only change slightly. Noise barriers above a viaduct raise concentration between barriers, but slightly reduce vehicular exposure in near-road buildings. Because people spend most of their time indoors, vehicular pollutant exposure within near-road buildings can be 6–9 times that at pedestrian level. Although further studies are still required to provide practical guidelines, this paper provides effective methodologies to quantify the impacts of street/viaduct configurations on human exposure for urban design purpose. [ABSTRACT FROM AUTHOR]

This paper presents a feasibility analysis for the installation of ground source heat pump systems in Cyprus. Two reference buildings, a single- and a multi-family one, are designed and analyzed using the EnergyPlus software, in order to calculate their energy needs for heating and cooling for the climate conditions of Cyprus, one of the warmest areas in Southern Europe. These energy needs are assumed to be covered by the conventional heating and cooling systems that are most widely used in Cyprus or alternatively by a ground source heat pump system, which consists of a vertical ground heat exchanger and water-to-water heat pumps and is analyzed using an in-house developed and validated code. Primary energy consumption and the resulting CO emissions for both the conventional and the alternative systems are calculated and compared. Results show that the installation of the ground source heat pump system achieves in most cases substantial reductions in primary energy use for both types of buildings. As regards carbon emissions, the findings are less clear: Emissions of the geothermal system are higher than those of the conventional system for the single-family building but considerably lower for the multi-family one. From an economic perspective, the geothermal system compares favorably with the conventional systems in many cases, particularly for the multi-family building. [ABSTRACT FROM AUTHOR]

In this paper, environmental impacts occurred by different type of fuel used in a double-chambered crematory were analyzed and evaluated. Four kinds of fuel, which are diesel, Liquefied Petroleum Gas (LPG), electricity and biomass gas derived from gasification, were selected, whereas 60 kg of human corpse was assumed. Methodologies proposed in this paper consist of Greenhouse Gas emission, and damages to human health with ecosystem, which were analyzed by ReCipe Midpoint and Endpoint V1.05. The utilization of electricity for cremation process resulted in highest Greenhouse Gas (GHG) emission, which was 388 kgCO 2 -eq. At a same time, it was discovered high amount of GHG releasing from utilization of biomass producer gas, due to amount of fuel consumption and fuel's carbon content. It was investigated that using of diesel and LPG caused of drastic human toxicity after cremation process, by the formation of nitrogen oxide and unburnt carbon monoxide occurred from deficient combustion. Consequently, these evaluation results promoted the benefit of biomass energy utilization, in order to reduce fossil depletion and toxic emission, and it can be implied as carbon neutral concept. Likewise, if electricity will be applied as fuel for cremation, increasing the ratio of green energy in electricity production can decrease the environmental impacts. [ABSTRACT FROM AUTHOR]

The results of a study on commuter exposure to carbon monoxide (CO) and PM10 during transit in the several commonly popular modes of transport in Mumbai, India, and Newcastle, U.K., are presented in this paper. In Mumbai, real-time exposure concentrations were measured while commuting along a route by bus, train, air-conditioned taxi, and a non-air-conditioned private car. In Newcastle, real-time exposure concentrations were measured while traveling by electric vehicle, public bus, and bicycle along a route. Average heart rate while commuting was monitored and subsequently simulated in a submaximal exercise test to give minute ventilation (VE) associated with each transport mode. The study in Mumbai has indicated that commuters traveling on buses and private non-air-conditioned cars are exposed to very high levels of air pollution compared with the train commuters. In Newcastle, electric vehicles and bicycles displayed the lowest exposure concentrations relative to buses. Higher exposure concentrations were observed for all travel modes in Mumbai as compared with Newcastle. When the inhaled amount and the lung deposition of pollutants are considered, cyclists are exposed to a higher amount of exposure dose in Newcastle because of the considerable increase in VE induced by the physical exertion of cycling. Thus, inhaled quantity and pollutant dosage give a better indication of the possible health risks and should be considered in future studies and in designing the cycle routes in cities. [ABSTRACT FROM AUTHOR]

This paper describes a numerical experiment to test the ability of the proposed geoCARB satellite to estimate emissions of trace gases (CO2, CH4 and CO) in the polluted urban environment of Shanghai. The meteorology over Shanghai is simulated with the Weather Research and Forecasting (WRF) model for a 9-day period in August 2010. The meteorology includes water and ice clouds. The chemistry version of WRF (WRF-Chem V3.6.1) is used to predict the chemical composition, mass density and number density of aerosol species. Spectra in the bands measured by geo-CARB are calculated, including the effects of polarisation and multiple scattering of radiation by clouds, aerosols and molecules. Instrument noise is added, and column-averaged trace-gas mole fractions are estimated from the noisy spectra using an algorithm based on that for the Greenhouse Gases Observing Satellite (GOSAT) and the Orbiting Carbon Observatory-2 (OCO-2) but adapted to geoCARB. As expected, the high aerosol loadings are challenging. However, when the retrieval algorithm is provided with regionally adjusted aerosol optical properties, as might be determined from observations of dark targets within the field of regard, the accuracies of retrieved concentrations are comparable to those reported earlier for geoCARB. Statistics of the errors in the retrieved column-averaged concentrations are used to predict the reduction in uncertainty of surface emissions possible with remotely sensed data. [ABSTRACT FROM AUTHOR]

The greater the use of energy in the transportation sectors, the higher the emission of carbon monoxide (CO), and hence inevitable harm to environment and human health. In this concern, measuring and predicting of CO emission from transportation sector-especially large cities-is important as it constitute 90 % of all CO emission. Many urban cities in developing world have not properly experienced such measurements or predictions. In this paper, for the first time, field measurements of traffic characteristics data and corresponding CO concentration have been performed for developing a model for predicting CO emissions from transportation sector for New Borg El Arab (NBC), Egypt. The performance of Swiss-German Handbook Emission Factors for Road Transport (HBEFA v3.1) model has been assessed for predicting the CO concentration at roadside in the study area. Results indicated that HBEFA v3.1 underestimate emission figures. The developed CO dynamic emission model involves the traffic flow characteristics with roadside CO concentrations. Acceptable representation of measured CO concentration has been shown by the developed dynamic CO emission model which introduces R = 0.77, mean biases and frictional biases of −0.27 mg m and 0.09, respectively. A comparison between predicted CO concentrations using HBEFA v3.1 and the promoted dynamic model indicate that HBEFA v3.1 estimates CO emission concentrations in the study area with a mean error and frictional biases 159.26 and 233.33 %, respectively, higher than those of the developed model. [ABSTRACT FROM AUTHOR]

The objective of this paper is to examine the dynamic impact of urbanization, economic growth, energy consumption, and trade openness on CO emissions in Nigeria based on autoregressive distributed lags (ARDL) approach for the period of 1971-2011. The result shows that variables were cointegrated as null hypothesis was rejected at 1 % level of significance. The coefficients of long-run result reveal that urbanization does not have any significant impact on CO emissions in Nigeria, economic growth, and energy consumption has a positive and significant impact on CO emissions. However, trade openness has negative and significant impact on CO emissions. Consumption of energy is among the main determinant of CO emissions which is directly linked to the level of income. Despite the high level of urbanization in the country, consumption of energy still remains low due to lower income of the majority populace and this might be among the reasons why urbanization does not influence emissions of CO in the country. Initiating more open economy policies will be welcoming in the Nigerian economy as the openness leads to the reduction of pollutants from the environment particularly CO emissions which is the major gases that deteriorate physical environment. [ABSTRACT FROM AUTHOR]

This paper analyses the international inequalities in $$\hbox {CO}_{2}$$ emissions intensity for the period 1971-2009 and assesses explanatory factors. Group, additive and multiplicative methodologies of inequality decomposition are employed. The first allows us to understand the role of regional groups; the second allows us to investigate the role of different fossil energy sources (coal, oil and gas); and the third allows us to clarify the separated role of the carbonisation index and the energy intensity in the pattern observed for inequalities in $$\hbox {CO}_{2}$$ intensities. The results show that, first, the reduction in global emissions intensity has coincided with a significant reduction in international inequality. Second, the bulk of this inequality and its reduction are attributed to differences between the groups of countries considered. Third, coal is the main energy source explaining these inequalities, although the growth in the relative contribution of gas is also remarkable. Fourth, the bulk of inequalities between countries and its decline are explained by differences in energy intensities, although there are significant differences in the patterns demonstrated by different groups of countries. The policy implications of these results are discussed. [ABSTRACT FROM AUTHOR]

Burning of fuels from the transport sector is one of the main sources of air pollutants emission in urban areas. In order to implement public policies concerning air quality and public health, there is a need to develop emission inventories. Measurements inside traffic tunnels can provide an evaluation of emission factors of vehicles in-use in real conditions. In this paper, we show measurements of air pollutants for a mixed vehicle fleet, heavy- and light-duty vehicles (HDVs and LDVs), in two tunnels in the metropolitan region of Sao Paulo in 2011 in order to calculate the pollutant emission factors (EFs). Measurements of carbon dioxide, carbon monoxide (CO), nitrogen oxides (NO) and particle matter (PM) were taken. High concentrations related to high-density traffic, especially during weekdays. EFs were heavily influenced by the pollutant species loads, so the total vehicle traffic and the fraction of HDV. The EF values for HDV were 3.6 and 9.2 g km, for CO and NO, respectively (5.8 and 0.3 g km for LDV). To determine EF estimates, parameters such as velocity of the air, cross-sectional area and length of the tunnel and vehicles passing at 1-h time interval were considered. [ABSTRACT FROM AUTHOR]

This paper uses the Global Trade Analysis Project (version 7) database to calculate embodied CO emissions in bilateral trade between China and other countries (regions) based on input-output methods. The sources and flows of embodied CO emissions in import and export trade of China are analyzed. Results show that the flows of embodied CO emissions in export trade are highly concentrated. The main flows to the United States (US) and Japan account for 1/4 and 1/7 of the total CO emissions in export trade, respectively. Concentrated flows of total exports and small differences in export structure are the main reasons for the highly concentrated export trade. The sources of embodied CO emissions in import trade have relatively low concentration. Taiwan Province of China, Hong Kong Special Administrative Region of China, US, Russia, Republic of Korea, and Japan account for around 7.72%-12.67% of the total embodied CO emissions in import trade. The relative dispersion of import sources, the impact of the import structure, and the level of production technology in importing countries caused low concentration of CO emissions in import trade. Overall, the embodied CO emissions in the export trade of China are higher than those in import trade. As a result, production-based CO emissions are higher than consumption-based CO emissions. The difference of 8.96 × 10 t of CO, which comes mainly from the US, Japan, Germany, and the United Kingdom, accounts for 58.70% of the total difference. Some suggestions, such as improving energy efficiency, alerting high carbon-intensive industries transfer, expanding the market for sharing risks, and prompting the accounting system of consumption-based CO emissions, are proposed based on the results. [ABSTRACT FROM AUTHOR]

This paper is a critical synthesis of the causes, effects and challenges of the Sahelian droughts. The results show that the four main causes of the Sahelian droughts are as follows: sea surface temperature changes, vegetation and land degradation, dust feedbacks and human-induced climate change. However, human-induced climate change is seen as the major drought-determining factor because it controls sea surface temperatures, dust feedbacks and vegetation degradation. Increase rainfall and greening have been observed in the Sahel since the 1990s; yet, food yields remain low while tree mortality rates are high. The implication of this is that the rainfall is not available for agriculture since various human-induced climate change processes such as deforestation and the expansions of arable farms do not make the moisture available for agriculture. The increase in tree mortality has also been found to increase atmospheric CO in the study area. However, this study hypothesizes that the increase in CO might be responsible for the increase in greening and rainfall observed. This can be explained by an increased aerial fertilization effect of CO that triggers plant productivity and water management efficiency through reduced transpiration. Also, the increase greening can be attributed to rural-urban migration which reduces the pressure of the population on the land. The remittances from migrant urban workers may make farming more sustainable in the rural areas, thus enhancing greening. The principal challenges in overcoming the effects of the droughts are HIV/AIDS and Malaria, political instability, data availability, proliferation of extensive non-mechanized farms and lack of adequate observations. [ABSTRACT FROM AUTHOR]

Tropical fires represent a highly uncertain source of atmospheric methane (CH4) because of the variability of fire emissions and the dependency of the fire CH4 emission factors (g kg-1 dry matter burned) on fuel type and combustion phase. In this paper we use new observations of CH4 and CO in the free troposphere from the Aura Tropospheric Emission Sounder (TES) satellite instrument to place constraints on the role of tropical fire emissions versus microbial production (e.g. in wetlands and livestock) during the (October) 2006 El Niño, a time of significant fire emissions from Indonesia. We first compare the global CH4 distributions from TES using the GEOS-Chem model. We find a mean bias between the observations and model of 26.3 ppb CH4 that is independent of latitude between 50° S and 80° N, consistent with previous validation studies of TES CH4 retrievals using aircraft measurements. The slope of the distribution of CH4 versus CO as observed by TES and modeled by GEOSChem is consistent (within the TES observation error) for air parcels over the Indonesian peat fires, South America, and Africa. The CH4 and CO distributions are correlated between R = 0.42 and R = 0.46, with these correlations primarily limited by the TES random error. Over Indonesia, the observed slope of 0.13 (ppb ppb-1) ±0.01, as compared to a modeled slope of 0.153 (ppb ppb-1) ±0.005 and an emission ratio used within the GEOS-Chem model of approximately 0.11 (ppb ppb-1), indicates that most of the observed methane enhancement originated from the fire. Slopes of 0.47 (ppb ppb-1) ±0.04 and 0.44 (ppb ppb-1) ±0.03 over South America and Africa show that the methane in the observed air parcels primarily came from microbial-generated emissions. Sensitivity studies using GEOS-Chem show that part of the observed correlation for the Indonesian observations and most of the observed correlations over South America and Africa are a result of transport and mixing of the fire and nearby microbial-generated emissions into the observed air parcels. Differences between observed and modeled CH4 distributions over South America and southern Africa indicate that the magnitude of the methane emissions for this time period are inconsistent with observations even if the relative distribution of fire versus biotic emissions are consistent. This study shows the potential for estimation of CH4 emissions over tropical regions using joint satellite observations of CH4 and CO. [ABSTRACT FROM AUTHOR]

In the present paper the effect of an abrupt change of the atmospheric radiative forcing is investigated by means of a global climate model that includes a mixed layer ocean. In assessing if, under such a change, the model response has a bifurcation point, the steady solution is studied for a sudden decrease of CO concentration from its actual value. It is found that there is a critical threshold for CO content below which the model ends up to a snowball Earth. It occurs for a few percentage changes of CO concentration around the threshold because the model strongly depends on the relationship among atmospheric temperature, water vapor content and the sudden ice-albedo feedback activation, even in the subtropical regions. Moreover, results suggest that the transition to ice-covered Earth is clearly favoured when Q-flux corrections (i.e. the parameterization of ocean heat transports) are removed. [ABSTRACT FROM AUTHOR]

Microalgae have been proposed as a CO removal option to contribute to climate change avoidance and problems coming from the use of fossil fuels. However, even though microalgae can be used to fix CO from air or flue gases, they do not permit long-term CO storage because they are easily decomposed. On the other hand, microalgae can contribute to an enhancement in human sustainability by producing biofuels as an alternative to fossil fuels in addition to the production of other useful chemicals and commodities. Moreover, microalgae can contribute to enhancing the sustainability of waste treatment processes, reducing the energy consumed, and improving the recycling of nutrients contained within them. This paper reviews the potential contribution of these processes and the existing knowledge in these areas. [ABSTRACT FROM AUTHOR]

This paper estimates CO fluxes in a municipal site for final disposal of solid waste, located in Gualeguaychu, Argentina. Estimations were made using the accumulation chamber methods, which had been calibrated previously in laboratory. CO fluxes ranged from 31 to 331 g m day. Three different populations were identified: background soil gases averaging 46 g m day, intermediate anomalous values averaging 110 g m day and high anomalous values averaging 270 g m day. Gas samples to a depth of 20 cm were also taken. Gas fractions, XCO < 0.1, XCH < 0.01, XN ~0.71 and XO ~0.21, δC of CO (−34 to −18‰), as well as age of waste emplacement, suggest that the study site may be at the final stage of aerobic biodegradation. In a first approach, and following the downstream direction of groundwater flow, alkalinity and δC of dissolved inorganic carbon (−15 to 4‰) were observed to increase when groundwater passed through the disposal site. This suggests that the CO generated by waste biodegradation dissolves or that dissolved organic matter appears as a result of leachate degradation. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of hydrogen (H2) addition on the exhaust emissions of a 1999 Cummins ISM370 heavy-duty diesel engine with H2 continuously supplemented to intake air. Using the 13-mode European Stationary Cycle (ESC), the addition of 2 per cent H2 by volume increased the emissions of oxides of nitrogen (NOx) and nitrogen dioxide (NO2), but reduced nitric oxide (NO) emissions. The addition of 4 per cent H2 increased the emissions of NO, NO2, and NOx. When examined under constant load, the addition of H2 reduced the emissions of particulate matter (PM) and carbon monoxide (CO), but had very mild effects on hydrocarbon (HC) emissions. It was also shown that the reduction in PM emissions was due to the reduced diesel fuel flowrate rather than the improvement to the combustion efficiency of diesel fuel. However, the addition of a relatively large amount of H2 at medium to high (30–70 per cent) load substantially increased the emissions of NOx. This was due to an increase in maximum local combustion temperature resulting from the enhanced heat release rate, advanced combustion phasing, and reduced combustion duration. In comparison, the addition of a small amount of H2 had a very mild effect on NOx emissions. However, a substantial reduction in NOx emissions was observed with the addition of large amounts of H2 at 10–15 per cent load, which was due to deteriorated peak heat release rate observed at premixed combustion process and elongated diffusion combustion process, which reduced the peak local combustion temperature and retarded the combustion phasing. It was also noted that the addition of H2 substantially increased the emissions of NO2, indicating the significant effect of H2 addition in enhancing the conversion of NO to NO2. When measured using the 13-mode ESC, the addition of 2 per cent and 4 per cent H2 increased NO2 emissions by 300 per cent and 221 per cent, respectively. When measured under constant load, a maximum NO2/NOx ratio of 62.2 per cent was obtained with the addition of 4 per cent H2 at 10 per cent load. [ABSTRACT FROM PUBLISHER]

A method is presented for the evaluation of the exhaust emissions of marine traffic, based on the messages provided by the Automatic Identification System (AIS), which enable the positioning of ship emissions with a high spatial resolution (typically a few tens of metres). The model also takes into account the detailed technical data of each individual vessel. The previously developed model was applicable for evaluating the emissions of NOx, SOx and CO2. This paper addresses a substantial extension of the modelling system, to allow also for the mass-based emissions of particulate matter (PM) and carbon monoxide (CO). The presented Ship Traffic Emissions Assessment Model (STEAM2) allows for the influences of accurate travel routes and ship speed, engine load, fuel sulphur content, multiengine setups, abatement methods and waves. We address in particular the modeling of the influence on the emissions of both engine load and the sulphur content of the fuel. The presented methodology can be used to evaluate the total PM emissions, and those of organic carbon, elemental carbon, ash and hydrated sulphate. We have evaluated the performance of the extended model against available experimental data on engine power, fuel consumption and the composition-resolved emissions of PM. We have also compared the annually averaged emission values with those of the corresponding EMEP inventory, As example results, the geographical distributions of the emissions of PM and CO are presented for the marine regions of the Baltic Sea surrounding the Danish Straits. [ABSTRACT FROM AUTHOR]

Significant amounts of carbon and nutrients are released to the atmosphere due to large fires in forests. Characterization of the spatial distribution and temporal variation of the intense fire emissions is crucial for assessing the atmospheric loadings of trace gases and aerosols. This paper discusses issues of the representation of forest fires in the estimation of emissions and the application to an atmospheric chemistry transport model (CTM). The potential contribution of forest fires to the deposition of bioavailable iron (Fe) into the ocean is highlighted, with a focus on mega fires in eastern Siberia. Satellite products of burned area, active fire, and land cover are used to estimate biomass burning emissions in conjunction with a biogeochemical model. Satellite-derived plume height from MISR is used for the injection height of boreal forest fire emissions. This methodology is applied to quantify fire emission rates in each three-dimensional grid location in the high latitude Northern Hemisphere (>30° N latitude) over a 5-yr period from 2001 to 2005. There is large interannual variation in forest burned area during 2001-2005 (13-49 x 10³ km² yr-1) which results in a corresponding variation in the annual emissions of carbon monoxide (CO) (14-81 Tg CO yr-1). Satellite observations of CO column from MOPITT are used to evaluate the model performance in simulating the spatial distribution and temporal variation of the fire emissions. The model results for CO enhancements due to eastern Siberian fires are in good agreement with MOPITT observations. These validation results suggest that the model using emission rates estimated in this work is able to describe the interannual changes in CO due to intense forest fires. Bioavailable iron is derived from atmospheric processing of relatively insoluble iron from desert sources by anthropogenic pollutants (mainly sulfuric acid formed from oxidation of SO2) and from direct emissions of soluble iron from combustion sources. Emission scenarios for IPCC AR5 report (Intergovernmental Panel on Climate Change; Fifth Assessment Report) suggest that anthropogenic SO2 emissions are suppressed in the future to improve air quality. In future warmer and drier climate, severe fire years such as 2003 may become more frequent in boreal regions. The fire emission rates estimated in this study are applied to the aerosol chemistry transport model to examine the relative importance of biomass burning sources of soluble iron compared to those from dust sources. The model reveals that extreme fire events contribute to a significant deposition of soluble iron (20-40%) to downwind regions over the western North Pacific Ocean, compared to the dust sources with no atmospheric processing by acidic species. These results suggest that the supply of nutrients from large forest fires plays a role as a negative biosphere-climate feedback with regards to the ocean fertilization. [ABSTRACT FROM AUTHOR]

This paper provides an empirical analysis of the relative impacts of various factors on CO emissions from production of goods and services in China during two consecutive periods of 1992-1997 and 1997-2002. Results show that, on the positive side, level of final demand for goods and services was the main reason for the increase of production-source CO emission, while structure of net export has similar positive effect during the first period of 1992-1997. On the negative side, technology factors remains as the main factors reducing emissions. The level of net export played some role in the first period, but the effects were seen in the second period from energy intensity, fuel mix and input mix. The results suggest that economic structure be focused as an important factor for CO emission reduction, with construction and transport as two key industries to lower carbon emission. [ABSTRACT FROM AUTHOR]

This paper presents the development of an emissions-controlling technique for oil burners aimed especially to reduce oxides of nitrogen (NOx). Another emission of interest is carbon monoxide (CO). In this research, a liquid fuel burner is used. In the first part, five different radial air swirler blade angles, 30°, 40°, 45°, 50°, and 60°, respectively, have been investigated using a combustor with 163 mm inside diameter and 280 mm length. Tests were conducted using kerosene as fuel. Fuel was injected at the back plate of the swirler outlet. The swirler blade angles and equivalence ratios were varied. A NOx reduction of more than 28% and GO emissions reduction of more then 40% were achieved for blade angle of 60° compared to the 30° blade angle. The second part of this paper presents the insertion of an orifice plate at the exit plane of the air swirler outlet. Three different orifice plate diameters of 35, 40, end 45 mm were used with a 45° radial air twirler vane angle. The fuel flow rates end orifice plate's sizes were varied. NOx reduction of more than 30% and CO emissions reduction of more than 25% were obtained using the 25 mm diameter orifice plate compared to the test configuration without the orifice plate. The lest pert of this paper presents tests conducted using the air-staging method. An industrial oil burner system was investigated using the air staging method in order to reduce emission, especially NOx. Emissions reduction of 30% and 16.1% were obtained for NOx and CO emissions, respectively, when using air staging compared to the non-air-staging tests. [ABSTRACT FROM AUTHOR]

Abstract: Vehicular emitted air pollutant concentrations were studied near three types of roadways in Austin, Texas: (1) State Highway 71 (SH-71), a heavily traveled arterial highway dominated by passenger vehicles; (2) Interstate 35 (I-35), a limited access highway north of Austin in Georgetown; and (3) Farm to Market Road 973 (FM-973), a heavily traveled surface roadway dominated by truck traffic. Air pollutants examined include carbon monoxide (CO), oxides of nitrogen (NO x ), and carbonyl species in the gas-phase. In the particle phase, ultrafine particle (UFP) concentrations (diameter < 100 nm), fine particulate matter (PM2.5, diameter < 2.5 μm) mass and carbon content and several particle-bound organics were examined. All roadways had an upwind stationary sampling location, one or two fixed downwind sample locations and a mobile monitoring platform that characterized pollutant concentrations fall-off with increased distance from the roadways. Data reported in this paper focus on UFP while other pollutants and near-roadway chemical processes are examined in a companion paper. Traffic volume, especially heavy-duty traffic, wind speed, and proximity to the road were found to be the most important factors determining UFP concentrations near the roadways. Since wind directions were not consistent during the sampling periods, distances along wind trajectories from the roadway to the sampling points were used to study the decay characteristics of UFPs. Under perpendicular wind conditions, for all studied roadway types, particle number concentrations increased dramatically moving from the upwind side to the downwind side. The elevated particle number concentrations decay exponentially with increasing distances from the roadway with sharp concentration gradients observed within 100–150 m, similar to previously reported studies. A single exponential decay curve was found to fit the data collected from all three roadways very well under perpendicular wind conditions. No consistent pattern was observed for UFPs under parallel wind conditions. However, regardless of wind conditions, particle concentrations returned to background levels within a few hundred meters of the roadway. Within measured UFP size ranges, smaller particles (6–25 nm) decayed faster than larger ones (100–300 nm). Similar decay rates were observed among UFP number, surface, and volume. [Copyright &y& Elsevier]

The importance of natural gas engines is increasing due to low CO2 emissions. To optimize these engines, a direct injection valve has been developed that works with low pressure and is triggered purely electrical. The development of this valve has been supported by numerical simulations using a coupled boundary-element-method-finite-element-method (BEM-FEM) code. This paper deals with the interaction of theoretical considerations, numerical simulations, and measurements on the realized device. In order to achieve the prescribed electromagnetic forces, numerous aspects were considered. The exciting coil, the armature, and the stator geometry is of basic interest. Several concepts have been investigated. Finally, a simple but powerful concept is realized. The simulation results have been compared to measurements on the lately constructed valve. [ABSTRACT FROM AUTHOR]

Cogeneration plants are strongly sustained by EU energy policies, one of the best beneficiary of this technology being residential buildings. This paper focus on spark ignition engine as a cogeneration application in order to supply energy for domestic consumers. Are considered two aspects of this solution: the energetic aspect and the environmental one. The energetic aspect deals with the energetic ratios, while the environmental aspect refers to the nitrogen oxide and carbon monoxide emissions. [ABSTRACT FROM AUTHOR]

Data on the concentrations of non-methane hydrocarbons (NMHC), nitrogen oxide (NO), nitrogen dioxide (NO2), carbon monoxide (CO), and meteorological parameters (air temperature and solar radiation) were used to predict the concentration of tropospheric ozone using the Design-Ease software. These data were collected on hourly basis over a 12-month period. Sampling of the data was conducted automatically. The effect of the NMHC, NO, NO2,CO, temperature and solar radiation variables in predicting ozone concentrations was examined under two scenarios: (i) when NO is included with the absence of NO2; and (ii) when NO2 is addressed with the absence of NO. The results of these two scenarios were validated against ozone actual data. The predicted concentration of ozone in the second scenario (i.e., when NO2 is addressed) was in better agreement with the real observations. In addition, the paper indicated that statistical models of hourly surface ozone concentrations require interactions and non-linear relationships between predictor variables in order to accurately capture the ozone behavior. [ABSTRACT FROM AUTHOR]

Recent developments in satellite remote sensing technologies resulted in the ability to observe major pollution events such as dust and smoke around the world on a daily basis. Satellite imagery can sometimes detect long-range transport episodes. In this paper, a high CO episode at remote GAW station, Mt. Waliguan, detected by MOPITT CO dataset during the end of April 2002, is described. CO concentrations above 600 hPa almost doubled on 27 April and CMDL surface sample measurements also observed this significant CO enhancement. Using NCEP data, satellite fire products data and backward trajectory model we suggest that this high CO episode of 27 April is not a local pollution event, but that it is due to long-range transport from active biomass burning and biofuel burning areas located in the border areas of Pakistan and India. The trajectory cluster analysis shows that the origins of 5-day backward trajectories, for air masses reaching Mt. Waliguan station, at all altitudes, mainly overlap with the fire spot locations detected by TRMM data and biofuel burning in India. [ABSTRACT FROM AUTHOR]

Abstract: This paper discusses the effects of combustion conditions on PCDD/PCDF emissions from pulp and paper power boilers burning salt-laden wood waste. We found no correlation between PCDD/PCDF emissions and carbon monoxide emissions. A good correlation was, however, observed between PCDD/PCDF emissions and the concentration of stack polynuclear aromatic hydrocarbons (PAHs) in the absence of TDF addition. Thus, poor combustion conditions responsible for the formation of products of incomplete combustion (PICs), such as PAHs and PCDD/PCDF precursors, increase PCDD/PCDF emissions. PAH concentrations increased with higher boiler load and/or low oxygen concentrations at the boiler exit, probably because of lower available residence times and insufficient excess air. Our findings are consistent with the current understanding that high ash carbon content generally favours heterogeneous reactions leading to either de novo synthesis of PCDD/PCDFs or their direct formation from precursors. We also found that, in grate-fired boilers, a linear increase in the grate/lower furnace temperature produces an exponential decrease in PCDD/PCDF emissions. Although the extent of this effect appears to be mill-specific, particularly at low temperatures, the results indicate that increasing the combustion temperature may decrease PCDD/PCDF emissions. It must be noted, however, that there are other variables, such as elevated ESP and stack temperatures, a high hog salt content, the presence of large amounts of PICs and a high Cl/S ratio, which contribute to higher PCDD/PCDFs emissions. Therefore, higher combustion temperatures, by themselves, will not necessarily result in low PCDD/PCDFs emissions. [Copyright &y& Elsevier]

Measurement of Pollution in the Troposphere (MOPITT) is an eight-channel gas correlation radiometer selected for the Earth Observing System AM-1 platform to be launched in 1999. Its primary objectives are the measurement of tropospheric carbon monoxide (CO) and methane (CH4 ). In this paper, the sensitivities of instrument signals and CO retrieval errors to various instrument parameters, especially the gas cell pressure and temperature variations, instrument radiometric noise, and ancillary data errors (such as atmospheric temperature and water vapor profile errors), are presented and discussed. In the MOPITT pressure modulator cell pressure sensitivity study, the instrument calibration process is considered, which leads to the relaxation of previous stringent requirements on the accuracy of in-orbit cell pressure monitoring. The approach of MOPITT CO retrieval error analysis is described, and the error analysis results are compared with retrieval simulation statistics. The error analysis results indicate that tropospheric CO distributions can be retrieved with a precision of 10percent for most of the troposphere. [ABSTRACT FROM AUTHOR]

Sustainable urban design is an effective way to improve urban ventilation and reduce vehicular pollutant exposure to urban residents. This paper investigated the impacts of urban open space and ‘lift-up’ building design on vehicular CO (carbon monoxide) exposure in typical three-dimensional (3D) urban canopy layer (UCL) models under neutral atmospheric conditions. The building intake fraction ( IF ) represents the fraction of total vehicular pollutant emissions inhaled by residents when they stay at home. The building daily CO exposure ( E t ) means the extent of human beings' contact with CO within one day indoor at home. Computational fluid dynamics (CFD) simulations integrating with these two concepts were performed to solve turbulent flow and assess vehicular CO exposure to urban residents. CFD technique with the standard k - ε model was successfully validated by wind tunnel data. The initial numerical UCL model consists of 5-row and 5-column (5 × 5) cubic buildings (building height H = street width W = 30 m) with four approaching wind directions ( θ = 0°, 15°, 30°, 45°). In Group I, one of the 25 building models is removed to attain urban open space settings. In Group II, the first floor (Lift-up1), or second floor (Lift-up2), or third floor (Lift-up3) of all buildings is elevated respectively to create wind pathways through buildings. Compared to the initial case, urban open space can slightly or significantly reduce pollutant exposure for urban residents. As θ = 30° and 45°, open space settings are more effective to reduce pollutant exposure than θ = 0° and 15°.The pollutant dilution near or surrounding open space and in its adjacent downstream regions is usually enhanced. Lift-up1 and Lift-up2 experience much greater pollutant exposure reduction in all wind directions than Lift-up3 and open space. Although further investigations are still required to provide practical guidelines, this study is one of the first attempts for reducing urban pollutant exposure by improving urban design. [ABSTRACT FROM AUTHOR]