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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]

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]

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]

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]

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]

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]

The paper presents the application of grey wolf algorithm for multidimensional engine optimization of converted parallel operated diesel plug-in hybrid electric vehicle to optimize specific fuel consumption (FC) and emissions. All emissions hydrocarbon (HC), carbon monoxide (CO), nitrogen oxide (NOx) and particulate matter (PM) are considered as optimization parameters. Offline engine maps of FC, HC, CO, NOx and PM are generated for 70 hp engine by data obtained from Oak Ridge National Laboratory for study. MATLAB program is used for simulation. A grey wolf coding is developed and tested extensively for various values of speed and torque. The optimization results obtained are verified by available engine maps. The optimization performance and its environmental impact are discussed in detail. It is observed that grey wolf optimizer (GWO) gives the global minimum value with slight deviation, although least computation time and simplicity makes this algorithm a potential candidate for real-time implementation. [ABSTRACT FROM AUTHOR]

This paper made a preliminary investigation of CO effects on lignite liquefaction process. The Schütze method coupled with an elemental analyzer was adopted for directly determining the O contents of liquid and solid materials, and the O balance, variation amounts of water, and CO consumptions were calculated quantitatively for liquefaction processes. It was found that the two reactions which were the water-gas shift reaction and the reaction between CO and organic structures of coals, occurred distinctly in the liquefaction process with CO atmospheres, and were simultaneously strengthened by the catalysts. The simultaneous occurrence of the two reactions played the roles of reducing the water production, elevating the coal conversion, and promoting the asphaltene (AS) and preasphaltene (PA) production. [ABSTRACT FROM AUTHOR]

This paper discusses the study on the measured harmful gases due to traffic emission in the Meru Menora Tunnel, a Malaysia highway tunnel. The hazardous gasses data would help in promoting essential ventilation system inside the tunnel for the health and safety of the users. The emission gasses concentration reading is divided into two main components comprise of Nitrogen Dioxide (NO2), and Carbon Monoxide (CO). Other than that, the visibility also been measured by using SICK sensor. The measurement has been done during normal, festive and school holiday seasons. Festive season shows the highest number of traffic and thus giving the worst air quality. Ventilation fan system can be activated based on the concentration level of gases and visibility in the tunnel. [ABSTRACT FROM AUTHOR]

In this paper, the concept of environmental indicator is reviewed as a relevant element used in the environmental management of any organisation. The importance of this element within an Environmental Management System (EMS) is also justified. Although EMS standards recognise the relevance of using indicators, they do not specify any methodology to identify which indicators have to be implemented. In addition, the present research demonstrates that although there is a high percentage of European ports that have already implemented performance indicators, most of them do not mention the method applied to obtain the indicators. This suggests that some of the procedures used by ports to identify indicators may not necessarily be science-based or systematic in approach. For these reasons, the need to develop a new methodology able to identify the ports' most adequate indicators was detected. Therefore, a Tool for the identification and implementation of Environmental Indicators in Ports (TEIP) was developed. It aims at identifying performance indicators in ports and providing guidelines for their proper implementation. This is a computer and science-based tool (www.eports.cat/teip) that provides a quick calculation and outputs, and it is designed to be as user-friendly and practical as possible in order to facilitate its completion by the user. This new methodology is applicable to all types of ports no matter the size, geographical location or its commercial profile; it provides targeted and specific results for each one. TEIP aims at helping port managers at easily determining their significant port indicators, which provides valuable elements for the decision-making processes. [ABSTRACT FROM AUTHOR]

This paper presents the retrieval and validation of a self-consistent time series of carbon monoxide (CO) above Kiruna using measurements from the Kiruna Microwave Radiometer (KIMRA). The data set currently spans the years 2008-2015, and measurements are ongoing at Kiruna. The spectra are inverted using an optimal estimation method to retrieve altitude profiles of CO concentrations in the atmosphere within an average altitude range of 48-84 km. Atmospheric temperature data from the Special Sensor Microwave Imager/Sounder aboard the US Air Force meteorological satellite DMSP-F18, are used in the inversion of KIMRA spectra between January 2011 and May 2014. This KIMRA CO data set is compared with CO data from the Microwave Limb Sounder aboard the Aura satellite: there is a maximum bias for KIMRA of ~0.65 ppmv at 68 km (corresponding to 14.7% of the mean CO value at 68 km) and a maximum relative bias of 22% (0.44 ppmv) at 60 km. Standard deviations of the differences between profiles are similar in magnitude to the estimated uncertainties in the profiles. Correlations between the instruments are within 0.87 and 0.94. These numbers indicate agreement between the instruments. To expand the CO data set outside of the lifetime of DMSP-F18, another inversion setup was used that incorporates modelled temperatures from the European Centre for Medium-Range Weather Forecasts. The effect on the retrieved CO profiles when using a different temperature data set in the inversion was assessed. A comparison of the two overlapping KIMRA CO data sets shows a positive bias of <5% in the extended data set and a correlation >0.98 between the lower retrievable altitude limit and 82.5 km. The extended data set shows a larger range (≤6 %) of CO concentrations that is not explained by random error estimates. Measurements are continuing and the extended KIMRA CO time series currently spans 2008-2015, with gaps corresponding to non-operation and summer periods when CO concentrations below ~90 km drop to very low values. [ABSTRACT FROM AUTHOR]

This paper describes the second phase of an Observing System Simulation Experiment (OSSE) that utilizes the synthetic measurements from a constellation of satellites measuring atmospheric composition from geostationary (GEO) Earth orbit presented in part I of the study. Our OSSE is focused on carbon monoxide observations over North America, East Asia and Europe where most of the anthropogenic sources are located. Here we assess the impact of a potential GEO constellation on constraining northern hemisphere (NH) carbon monoxide (CO) using data assimilation. We show how cloud cover affects the GEO constellation data density with the largest cloud cover (i.e., lowest data density) occurring during Asian summer. We compare the modeled state of the atmosphere (Control Run), before CO data assimilation, with the known “true” state of the atmosphere (Nature Run) and show that our setup provides realistic atmospheric CO fields and emission budgets. Overall, the Control Run underestimates CO concentrations in the northern hemisphere, especially in areas close to CO sources. Assimilation experiments show that constraining CO close to the main anthropogenic sources significantly reduces errors in NH CO compared to the Control Run. We assess the changes in error reduction when only single satellite instruments are available as compared to the full constellation. We find large differences in how measurements for each continental scale observation system affect the hemispherical improvement in long-range transport patterns, especially due to seasonal cloud cover. A GEO constellation will provide the most efficient constraint on NH CO during winter when CO lifetime is longer and increments from data assimilation associated with source regions are advected further around the globe. [ABSTRACT FROM AUTHOR]

To offer a scientific basis and reference for policy makers when developing the regulation framework for Chinese national carbon market, this research analyzes the environmental and economic effects of the carbon market from a mid- to long-term perspective in China. Through a computable general equilibrium model, with technological progress as an endogenous variable, this study provides a comprehensive investigation on the relationships between the price of carbon, technological development, emission reduction and economic growth in low, mid- and high emission reduction scenarios. Furthermore, it analyzes the potential of price-setting mitigation measures to create incentives for technological progress. The results indicate that the carbon market will have a positive impact on the R&D investment in China and in turn would promote technology development. Consequently, it is vital that the carbon price is high enough; otherwise, the pressure on technological development will not be sufficiently strong; there is compatibility between carbon intensity reduction and mid- and long-term GDP growth, but it seems impossible to realize the positive effects on both emission reduction and economy development at the early stage. Hence, the carbon market alone will not be a cost-effective instrument for emission abatement and other auxiliary policies will also be needed in the early stages. Meanwhile, selection of reasonable emission reduction scenarios will play a crucial role in achieving the pre-2020 and post-2020 carbon reduction commitments efficiently in China. [ABSTRACT FROM AUTHOR]

The evolution of perturbations in a two-layer spherical shell and a plane layer with a two-step density distribution has been simulated numerically. The clumps formed by instability are shown to have qualitatively different structures, depending on the ratio of the densities in the inner and outer layers of the shell. Inhomogeneities bordered by a dense gas are formed in shells with an outwardly decreasing density. If, however, a denser gas is in the outer layer, then cores surrounded by a more rarefied material appear. These results are used to analyze the expansion of the HII region RCW 82. Since the inhomogeneities observed in the CO emission in the outer parts of this region have sharply delineated boundaries, our calculations argue for the model of the expansion of a shell with an outwardly decreasing density. The interaction of an accelerating shell with clumps in front of it has also been investigated. The deformations of a clump during its penetration into the shell and the formation of a groove in the shell gradually fillingwith a cold gas have been revealed. Thereafter, the shell material collapses to form a cumulative jet. As applied to the HII region RCW 82, we conclude that the existence of jets is possible if there are inhomogeneities with a scale of ∼10 cm in the interstellar medium. The lack of data on such jet flows at the boundary of this region is an additional argument for the model where the inhomogeneous structure of the boundaries is attributable to the development of Rayleigh-Taylor instability. [ABSTRACT FROM AUTHOR]

Malaysia has abundant but underutilized oil palm fronds. Although the gasification of biomass using preheated inlet air as a gasifying medium is considered an efficient and environmentally friendly method, previous studies were limited to certain types of biomass wastes and gasifier designs. Hence, the effects of preheating the gasifying air on oil palm fronds gasification in a single throat downdraft gasifier are presented in this paper. In addition, the effects of varying the flow rate of the gasifying air and the moisture content of the feedstock on the outputs of oil palm fronds gasification were studied. A response surface methodology was used for the design of the experiment and the analysis of the results. The results showed that preheating the gasifying air to 500 °C increased the concentrations of CO from 22.49 to 24.98%, that of CH4 from 1.98 to 2.87%, and that of H2 from 9.67 to 13.58% on dry basis in the producer gas at a 10% feedstock moisture content. Conversely, the dry basis concentrations of CO, CH4, and H2 decreased from 22.49, 1.98 and 9.67% to 12.01, 1.44 and 5.45%, respectively, as the moisture content increased from 10 to 20%. The airflow rate was also proven to significantly affect the quality of the resulting producer gas. [ABSTRACT FROM AUTHOR]

Development of practical in-vehicle air quality vector time series models is useful for examining new (or enhancement of existing) control strategies for managing indoor air quality (IAQ) within the considered transit microenvironment. The models are helpful to the vehicle manufacturers in understanding the scope for preventing in-vehicle contaminant concentration buildup beyond permissible IAQ guidelines, and to the commuters in understanding the risks of exposure to various air contaminants. This study demonstrates the methodology to develop and validate the vector time series models (VARMA/VARMAX) for the in-bus contaminant concentrations of carbon dioxide and carbon monoxide using available software. © 2014 American Institute of Chemical Engineers Environ Prog, 33: 1069-1073, 2014 [ABSTRACT FROM AUTHOR]

The subsurface process of serpentinization creates an extreme environment for microbial life. This environment includes reducing, ultra‐basic groundwater that is limited in electron acceptors. Despite these challenging conditions, there is a great deal of potential energy available to support microbial metabolisms both in the anaerobic subsurface and in aerobic surface environments where serpentinization associated groundwater discharges. In this study, the available energy was quantified through the calculation of chemical affinities, Ar, for three sites of active serpentinization in North America: the Tablelands (NL, CAN), The Cedars (CA, USA), and Aqua de Ney (CA, USA). The results showed that Ar values for each reaction were similar for all sites studied; however, the available energy varied a great deal from reaction to reaction. For example, the reaction of carbon monoxide oxidation provided the most energy to the system followed closely by hydrogen oxidation and methanotrophy. Potential microbial metabolisms were tested, simulating surface and subsurface conditions, in a laboratory‐based setting using microcosms with materials from each site. During these microcosm experiments, carbon monoxide oxidation was not observed, and there was little evidence of methane oxidation. Unexpectedly, microbial methanogenesis was observed in methane oxidation microcosms using material collected from The Cedars. The microbial production of methane occurred despite the addition of electron acceptors demonstrating the broad tolerance of methanogens at The Cedars for less reducing conditions. Plain Language Summary: Ultramafic rocks are iron and magnesium rich rocks that are predominant deep inside the Earth and on other planets and moons. Groundwater that flows through and reacts with these rocks produces conditions that may not be conducive to life because they lack oxygen, have little nutrients and very high pH values. However, these systems have a large amount of chemical energy available to support life. Based on chemical analyses of water and gases collected from field sites, we calculated the amount of potential chemical energy available at three groundwater spring locations with these extreme conditions. These calculations were then used to predict biological metabolisms that would use this energy. We tested our predictions through a series of laboratory experiments. Many of the metabolisms for which we tested were not observed, despite available energy in the system, while an unexpected metabolism, microbial formation of methane, prevailed. Key Points: Chemical affinities were calculated for key metabolic reactions at three terrestrial sites of serpentinization: the Tablelands (NL, CAN), The Cedars (CA, USA), and Aqua de Ney (CA, USA)Calculated chemical affinities predicted methane oxidation would occur at these sites; however, microcosm experiments showed little evidence of methanotrophyMicrobial methanogenesis was inferred in microcosms from The Cedars [ABSTRACT FROM AUTHOR]

The biogeochemical evaluation toolkit, BGC-val, is a model- and grid-independent Python toolkit that has been built to evaluate marine biogeochemical models using a simple interface. Here, we present the ideas that motivated the development of the BGC-val software framework, introduce the code structure, and show some applications of the toolkit using model results from the Fifth Climate Model Intercomparison Project (CMIP5). A brief outline of how to access and install the repository is presented in Appendix A, but the specific details on how to use the toolkit are kept in the code repository. The key ideas that directed the toolkit design were model and grid independence, front-loading analysis functions and regional masking, interruptibility, and ease of use. We present each of these goals, why they were important, and what we did to address them. We also present an outline of the code structure of the toolkit illustrated with example plots produced by the toolkit. After describing BGC-val, we use the toolkit to investigate the performance of the marine physical and biogeochemical quantities of the CMIP5 models and highlight some predictions about the future state of the marine ecosystem under a business-as-usual CO2 concentration scenario (RCP8.5). [ABSTRACT FROM AUTHOR]

Abstract: Ambient air pollution by vehicular emissions is underestimated, especially in the major cities of Nigeria. The buildup of the emissions in the atmosphere is a major health concern. This study estimated the emissions of gaseous criteria air pollutants (CAPs) from the road transport system in the Lagos metropolis from the year 2004 to 2007. The study also determined the ground‐level concentrations of these pollutants for the years under review. Estimation of the emission rates of all types of vehicles was performed using an emission factor approach, while the ground‐level concentrations of the CAPs were determined using the Industrial Source Complex Short Term 3 view model. The results showed that the mean concentrations of carbon monoxide in the ambient air were 26,741.12, 31,675.95, 54,515.48, and 72,388.09 micrograms per cubic meter (μg/m3) for years 2004, 2005, 2006, and 2007, respectively, while the estimated concentrations for oxides of nitrogen were 1,377.91 μg/m3 for year 2004, and 1,620.76, 2,897.33, and 3,839.68 μg/m3, respectively, for the years 2005, 2006, and 2007. The estimated concentrations of sulfur dioxide during the study period were 51,354.16, 57,244.76, 113,083.26, and 136,332.01 μg/m3 for 2004, 2005, 2006, and 2007, respectively. For volatile organic compounds, the estimated concentrations were 3,839.68, 6,839.65, 7,067.62, and 8,431.35 μg/m3 for years 2004, 2005, 2006, and 2007, respectively. The results also show that the maximum ground‐level concentrations were highest along the roadside, and the average CAPs concentrations and cumulative exposure concentrations that were estimated throughout the study period are a major health concern, as these concentrations are several times higher than international limits. [ABSTRACT FROM AUTHOR]

Ground and satellite observations show that air pollution regulations in the United States (US) have resulted in substantial reductions in emissions and corresponding improvements in air quality over the last several decades. However, large uncertainties remain in evaluating how recent regulations affect different emission sectors and pollutant trends. Here we show a significant slowdown in decreasing US emissions of nitrogen oxides (NOx) and carbon monoxide (CO) for 2011-2015 using satellite and surface measurements. This observed slowdown in emission reductions is significantly different from the trend expected using US Environmental Protection Agency (EPA) bottom-up inventories and impedes compliance with local and federal agency air-quality goals. We find that the difference between observations and EPA's NOx emission estimates could be explained by: (i) growing relative contributions of industrial, area, and off-road sources, (ii) decreasing relative contributions of on-road gasoline, and (iii) slower than expected decreases in on-road diesel emissions. [ABSTRACT FROM AUTHOR]

The CHRONOS space mission concept provides time-resolved abundance for emissions and transport studies of the highly variable and highly uncertain air pollutants carbon monoxide and methane, with sub-hourly revisit rate at fine ( ~4 km) horizontal spatial resolution across a North American domain. CHRONOS can provide complete synoptic air pollution maps ("snapshots") of the continental domain with less than 10 min of observations. This rapid mapping enables visualization of air pollution transport simultaneously across the entire continent and enables a sentinel-like capability for monitoring evolving, or unanticipated, air pollution sources in multiple locations at the same time with high temporal resolution. CHRONOS uses a compact imaging gas filter correlation radiometer for these observations, with heritage from more than 17 years of scientific data and algorithm advances by the science teams for the Measurements of Pollution in the Troposphere (MOPITT) instrument on NASA's Terra spacecraft in low Earth orbit. To achieve continental-scale sub-hourly sampling, the CHRONOS mission would be conducted from geostationary orbit, with the instrument hosted on a communications or meteorological platform. CHRONOS observations would contribute to an integrated observing system for atmospheric composition using surface, suborbital and satellite data with atmospheric chemistry models, as defined by the Committee on Earth Observing Satellites. Addressing the U.S. National Academy's 2007 decadal survey direction to characterize diurnal changes in tropospheric composition, CHRONOS observations observations would find direct societal applications for air quality management and forecasting to protect public health. [ABSTRACT FROM AUTHOR]

Since 1994, the In-service Aircraft for a Global Observing System (IAGOS) program has produced in situ measurements of the atmospheric composition during more than 51 000 commercial flights. In order to help analyze these observations and understand the processes driving the observed concentration distribution and variability, we developed the SOFT-IO tool to quantify source-receptor links for all measured data. Based on the FLEXPART particle dispersion model (Stohl et al., 2005), SOFT-IO simulates the contributions of anthropogenic and biomass burning emissions from the ECCAD emission inventory database for all locations and times corresponding to the measured carbon monoxide mixing ratios along each IAGOS flight. Contributions are simulated from emissions occurring during the last 20 days before an observation, separating individual contributions from the different source regions. The main goal is to supply added-value products to the IAGOS database by evincing the geographical origin and emission sources driving the CO enhancements observed in the troposphere and lower stratosphere. This requires a good match between observed and modeled CO enhancements. Indeed, SOFT-IO detects more than 95% of the observed CO anomalies over most of the regions sampled by IAGOS in the troposphere. In the majority of cases, SOFT-IO simulates CO pollution plumes with biases lower than 10-15 ppbv. Differences between the model and observations are larger for very low or very high observed CO values. The added-value products will help in the understanding of the trace-gas distribution and seasonal variability. They are available in the IAGOS database via http://www.iagos.org. The SOFT-IO tool could also be applied to similar data sets of CO observations (e.g., ground-based measurements, satellite observations). SOFT-IO could also be used for statistical validation as well as for intercomparisons of emission inventories using large amounts of data. [ABSTRACT FROM AUTHOR]

Experiments for studying the effects of climatic change on ecosystems often involve manipulation of one or several quantitative treatment factors of interest. Response surface regression is the method of choice for these types of experiment. Here, we describe the development of a design of a free air CO2 enrichment experiment with two quantitative treatment factors, that is, elevated temperature and CO2 enrichment. The design strategy takes account of budget constraints imposing limitations on the number of plots with elevated temperature and CO2 levels. The approach is based on polynomial regression models and is focussed on an efficient estimation of interaction between the two treatment factors. Extension to more than two factors is straightforward. An analysis of soil moisture data demonstrates the overall suitability of the proposed design to analyse non-linear interactions of two (or more) global change factors. [ABSTRACT FROM AUTHOR]

There is concern about the hazard of acute residential CO exposures from portable gasoline-powered generators, which can result in death or serious adverse health effects in exposed individuals. To address this hazard, the U.S. Consumer Product Safety Commission has developed low CO emission prototype generators by adapting off-the-shelf emission control technologies onto commercially available generators. A series of tests was conducted to characterize the indoor CO concentrations resulting from portable generators operating in the attached garage of a research house under seven different test house/garage configurations. The tested generators include both unmodified and modified low CO emission prototypes. It was found that CO concentrations varied widely, with peak house CO concentrations ranging from under 10 ppm to over 10,000 ppm. The highest concentrations in the house resulted from operation of the unmodified generator in the garage with the garage bay door closed and the house access door open. The lowest concentrations resulted from operation of a modified low CO emission prototype in the garage with the garage bay door open and the house access door closed. These tests documented reductions of up to 98% in CO concentrations due to emissions from two low CO emission portable generators compared to a stock generator. Implications: Improper portable generator use has caused 800 U.S. deaths in the past 14 years. Generators operated in attached garages can cause CO to quickly reach deadly levels. Two low-emission prototypes generators were tested and had CO emissions reduced by up to 98%. Low-emission generators can reduce the risk of consumer poisonings and deaths. [ABSTRACT FROM AUTHOR]

We explored the underlying patterns of temporal stream CO partial pressure ( pCO) variability using high-frequency sensors in seven disparate headwater streams distributed across the northern hemisphere. We also compared this dataset of >40,000 pCO records with other published records from lotic systems. Individual stream sites exhibited relatively distinct pCO patterns over time with few consistent traits across sites. Some sites showed strong diel variability, some exhibited increasing pCO with increasing discharge, whereas other streams had reduced pCO with increasing discharge or no clear response to changes in flow. The only 'universal' signature observed in headwater streams was a late summer pCO maxima that was likely driven by greatest rates of organic matter respiration due to highest annual temperatures. However, we did not observe this seasonal pattern in a southern hardwood forest site, likely because the region was transitioning from a severe drought. This work clearly illustrates the heterogeneous nature of headwater streams, and highlights the idiosyncratic nature of a non-conservative solute that is jointly influenced by physics, hydrology, and biology. We suggest that future researchers carefully select sensor locations (within and among streams) and provide additional contextual information when attempting to explain pCO patterns. [ABSTRACT FROM AUTHOR]

Erbil-Gwer Road refineries were not built according to the standard regulations. Hence, distillation tower, storage tanks, and flare sections of the refinery release the hydrogen sulfide (H2S) and carbon monoxide (CO). At present, the measurements of H2S and CO were taken in one of the Erbil-Gwer Road refineries to determine the risk level of these gases to human health and environment. Khurmala, Tawke, and Demir dagh crude oils having different properties, were utilized. According to the study performed, one could conclude that (i) several poisonous gases like H2S and CO are released by the Refineries into the atmosphere of refinery and nearby the refinery that have the dangerous impact on the health and environment; (ii) the hydrogen sulfide and carbon monoxide diffusion rate from flare, storage tank and distillation tower is higher than the standard rate; (iii) As Iraqi crude oil has high sulfur content than other crude oil and the proportion of sulfur is differ from one location to another, the utilization of this kind petroleum in Refinery is the cause the production of poisonous gases; (iv) wind highly impacts the diffusion of hydrogen sulfide and carbon monoxide. Hydrogen sulfide and carbon monoxide spread further from the source of these gases by increasing wind speed, (v) the effect of atmospheric temperature cannot be neglected. The diffusion rate of H2S and CO gas is increased in higher atmospheric temperature. [ABSTRACT FROM AUTHOR]

One of the potential risks associated with subsurface storage of CO is the seepage of CO through existing faults and fractures. There have been a number of studies devoted to this topic. Some of these studies show that geochemistry, especially mineralization, plays an important role in rendering the faults as conduits for CO movement while others show that mineralization due to CO injection can result in seep migration and flow diversion. Therefore, understanding the changes in reservoir properties due to pore alterations is important to ensure safe long term CO storage in the subsurface. We study the changes in the Representative Elementary Volume (REV) of a rock due to reactive kinetics over a time, using a statistical approach and pore-scale CO-rock interactiondata. The goal of this study is to obtain the REV of a rock property that accounts for pore-scale changes over time due to reactive kinetics, and we call this as spatiotemporal REV. Scale-up results suggest that the REV changes with time when CO-rock interaction is considered. It is hypothesized that the alteration in pore structure introduces more heterogeneity in the rock, and because of this the magnitude of REV increases. It is possible that these noticeable changes in REV at pore-scale may have an impact when analyzed at the reservoir scale. [ABSTRACT FROM AUTHOR]

We investigate the composition of 63 C-C nonmethane hydrocarbons (NMHCs), methane (CH) and carbon monoxide (CO), in Jeddah, Mecca, and Madina (Saudi Arabia), in Lahore, (Pakistan), and in Singapore. We established a database with which to compare and contrast NMHCs in regions where ambient levels and emissions are poorly characterized, but where conditions are favorable to the formation of tropospheric ozone, and where measurements are essential for improving emission inventories and modeling. This dataset will also serve as a base for further analysis of air pollution in Western Saudi Arabia including, but not limited to, the estimation of urban emissions and long range pollution transport from these regions. The measured species showed enhanced levels in all Saudi Arabian cities compared to the local background but were generally much lower than in Lahore. In Madina, vehicle exhaust was the dominant NMHC source, as indicated by enhanced levels of combustion products and by the good correlation between NMHCs and CO, while in Jeddah and Mecca a combination of sources needs to be considered. Very high NMHC levels were measured in Lahore, and elevated levels of CH in Lahore were attributed to natural gas. When we compared our results with 2010 emissions from the MACCity global inventory, we found discrepancies in the relative contribution of NMHCs between the measurements and the inventory. In all cities, alkenes (especially ethene and propene) dominated the hydroxyl radical (OH) reactivity ( k ) because of their great abundance and their relatively fast reaction rates with OH. [ABSTRACT FROM AUTHOR]

We propose an algorithm that combines a pre-processing step applied to the a priori state vector prior to retrievals, with the modified damped Newton method (MDNM), to improve convergence. The initial constraint vector pre-processing step updates the initial state vector prior to the retrievals if the algorithm detects that the initial state vector is far from the true state vector in extreme cases where there are CO emissions. The MDNM uses the Levenberg-Marquardt parameter γ, which ensures a positive Hessian matrix, and a scale factor α, which adjusts the step size to optimize the stability of the convergence. While the algorithm iteratively searches for an optimized solution using observed spectral radiances, MDNM adjusts parameters γ and α to achieve stable convergence. We present simulated retrieval samples to evaluate the performance of our algorithm and comparing it to existing methods. The standard deviation of our retrievals adding random noise was less than 3.8 ppmv. After pre-processing the initial estimate when it was far from the true value, the CO retrieval errors in the boundary layers were within 1.2 ppmv. We tested the MDNM algorithm's performance using GOSAT L1b data with cloud screening. Our preliminary validations comparing the results to TCCON FTS measurements showed that the average bias was less than 1.8 ppm and the correlation coefficient was approximately 0.88, which was larger than for the GOSAT L2 product. [ABSTRACT FROM AUTHOR]