An estimate of regional and global O3 damage from precursor NOx and VOC emissions

The results of the ozone models of EMEP and Harwell are combined with the C-R (concentration- response) functions and economic valuation recommended by the ExternE Project of the European Commission. The paper is exploratory, to assemble the available information, establish likely priority impact categories, and make recommendations for future research. Impacts on health and agriculture are evaluated. Based on the EMEP results, aggregate regional (Europe-wide) estimates of ozone damage, allocated per ton of precursor emission, are derived. Calculations on the global scale, using results from the Harwell Global Ozone Model (and the same valuation per nL/L O₃) indicate that damages outside Europe are likely to also be significant although somewhat smaller. For the EMEP Model, the numbers per ton of precursor emission are approximately the same for NO_x and for VOC. For NO_x, a value around $1875 (uncertainty range 375 to 10 000) per Mg _{NO2 equi} was found; for VOC, approximately $1100 per Mg_VOC was found. There is much uncertainty, especially in the C-R functions, and current assessments of ozone damages are, at best, order of magnitude estimates. Even though the overlap between local, regional, and global models is not clear, the results suggest that ozone damage is dominated by regional impacts.     

Relationships among personal,indoor and outdoor NO2 measurements

Using integrating NO₂ diffusion dosimeters, personal, indoor and outdoor exposures were measured for nine families in Topeka, Kansas. NO₂ exposures in homes that used gas for cooking were clearly different from those in homes that used electricity. The gas-cooking homes had indoor levels three times the outdoor levels. Members of the gas-cooking households had levels twice those of electric-cooking families and twice the outdoor levels. A linear model that includes outdoor concentrations and stove types explains 77% of the variance in observed NO₂ exposure. The differential NO₂ exposures in homes with and without gas stoves should be considered in epidemiologic studies of the health effects of air pollution.     

A badge-type personal sampler for measurement of personal exposure to NO2 and NO in ambient air

A badge-type personal sampler was developed for measuring personal exposure to nitrogen dioxide (NO₂). An absorbent sheet containing triethanolamine (TEA) solution absorbed NO₂ which diffused through five layers of hydrophobic fiber filter. Wind effects on absorption rate were suppressed by these filter layers. NO₂ was measured by the sampler with a sensitivity of 124.8 μg h/m³ (66 ppb h) and an accuracy of within ± 20%. It could be used for measuring personal exposure to NO₂ without interfering with the wearer's daily activities. Nitric oxide (NO) could be measured after a small modification to the sampler provided oxidation ability to the layers of diffusion filter. Three layers of hydrophobic fiber filter were replaced by 12 layers of glass fiber filter containing chromium trioxide solution. NO was oxidized to NO₂ in the oxidation layers and absorbed by the absorbent sheet together with the coexisting NO₂. Sensitivity and accuracy of the sampler for NO were nearly equal to that for NO₂.     

Characteristics of PM10, PM2.5, CO2 and CO monitored in interiors and platforms of subway train in Seoul, Korea

This study was performed to investigate the concentration of PM₁₀ and PM_2.5 inside trains and platforms on subway lines 1, 2, 4 and 5 in Seoul, KOREA. PM₁₀, PM_2.5, carbon dioxide (CO₂) and carbon monoxide (CO) were monitored using real-time monitoring instruments in the afternoons (between 13:00 and 16:00). The concentrations of PM₁₀ and PM_2.5 inside trains were significantly higher than those measured on platforms and in ambient air reported by the Korea Ministry of Environment (Korea MOE). This study found that PM₁₀ levels inside subway lines 1, 2 and 4 exceeded the Korea indoor air quality (Korea IAQ) standard of 150 μg/m³. The average percentage that exceeded the PM₁₀ standard was 83.3% on line 1, 37.9% on line 2 and 63.1% on line 4, respectively. PM_2.5 concentration ranged from 77.7 μg/m³ to 158.2 μg/m³, which were found to be much higher than the ambient air PM_2.5 standard promulgated by United States Environmental Protection Agency (US-EPA) (24 h arithmetic mean: 65 μg/m³). The reason for interior PM₁₀ and PM_2.5 being higher than those on platforms is due to subway trains in Korea not having mechanical ventilation systems to supply fresh air inside the train. This assumption was supported by the CO₂ concentration results monitored in tube of subway that ranged from 1153 ppm to 3377 ppm. The percentage of PM_2.5 in PM₁₀ was 86.2% on platforms, 81.7% inside trains, 80.2% underground and 90.2% at ground track. These results indicated that fine particles (PM_2.5) accounted for most of PM₁₀ and polluted subway air. GLM statistical analysis indicated that two factors related to monitoring locations (underground and ground or inside trains and on platforms) significantly influence PM₁₀ (p < 0.001, R² = 0.230) and PM_2.5 concentrations (p < 0.001, R² = 0.172). Correlation analysis indicated that PM₁₀, PM_2.5, CO₂ and CO were significantly correlated at p < 0.01 although correlation coefficients were different. The highest coefficient was 0.884 for the relationship between PM₁₀ and PM_2.5.     

The history of CO2

Upon arrival on Earth, the reduced carbon pool split into a series of compartments: core, mantle, crust, hydrosphere, atmosphere, biosphere.This distribution pattern is caused by the ability of carbon to adjust structurally to a wide range of pressure and temperature, and to form simple and complex molecules with oxygen, hydrogen and nitrogen. Transformation also involved oxidation of carbon to CO₂ which is mediated at depth by minerals, such as magnetite, and by water vapor above critical temperature. Guided by mineral-organic interactions, simple carbon compounds evolved in near surface environments towards physiologically interesting biochemicals. Life, as an autocatalytic system, is considered an outgrowth of such a development.This article discusses environmental parameters that control the CO₂ system, past and present. Mantle and crustal evolution is the dynamo recharging the CO₂ in sea and air; the present rate of CO₂ release from the magma is 0.05 × 10¹⁵ g C per year. Due to the enormous buffer capacity of the chemical system ocean, such rates are too small to seriously effect the level of CO₂ in our atmosphere. In the light of geological field data and stable isotope work, it is concluded that the CO₂ content in the atmosphere has remained fairly uniform since early Precambrian time; CO₂ should thus have had little impact on paleoclimate. In contrast, the massive discharge of man-made CO₂ into our atmosphere may have serious consequences for climate, environment and society in the years to come.     

Formation of NO2 in range-top burners

This paper describes results of a study that examined NO and NO₂ formation on range-top burners and in diffusion flames. These flames were characterized by composition and temperature profiles. Range-top burner flames and pilot flames displayed qualitatively similar behavior with respect to the kinds of flame regions in which relatively high NO₂/NO ratios were identified. These regions of high NO₂/NO ratios were consistently either regions of low oxygen concentration or flame surfaces subjected to thermal quenching. A limited series of experiments with modified burners indicated that reduced emissions from both the RTB and pilot flames could be achieved by (1) improved primary aeration, using 50% or greater primary air, and (2) using flame geometries designed to minimize flame surface, e.g., flat-flame burners or other designs having effectively fewer distinct ports. Both NO and NO₂ are readily produced in diffusion and partially premixed Bunsen-type flames, mainly in the vicinity of the hot visible zone. High NO₂/NO ratios are associated with the cooler regions of the flame, as, for example, at the base of the flame in the highly diluted downstream region and in the fuel-rich regions of the flames. A simplified reaction mechanism based on CN and NH radicals being oxidized to NO followed by NO + HO₂ → NO₂ + OH appears to explain the high NO₂/NO ratios observed. A practical implication of the study is that a burner designed with improved aeration and mixing minimization of flame surface should emit less NO₂.     

International trade,carbon leakage,and CO2 emissions of manufacturing industry

Foreign trade drives China’s growth,but as the trade scale continues to expand,the carbon emissions also increase quickly.Based on the industry panel data from 1996 to 2010,this paper calculates carbon emissions of 27manufacturing industries.According to the intensity of carbon emissions,this paper divides the manufacturing sectors into low carbon and high carbon manufacturing industry and then analyzes the carbon emission trends.Next,the paper uses the feasible generalized least square regression to verify the existence of environmental Kuznets curve（EKC）of the manufacturing industry’s carbon.In order to investigate the carbon leakage problem,the regression also includes the interaction term between trade and industrial value added.Our findings are as follows:the carbon emissions of the whole manufacturing industry and low carbon manufacturing industry accord with the EKC curve,but have a linear relationship with the high carbon manufacturing industry;trade reduces the carbon emissions of the whole manufacturing industry and low carbon manufacturing industry,but it increases those of the high carbon manufacturing industry;for the whole manufacturing industry and low carbon manufacturing industry,there is no carbon leakage,but it exists in the high carbon manufacturing industry.On the whole,pollution haven hypothesis does not hold up in China,and China does not need to limit industry foreign trade to reduce the emission of CO₂.But the manufacturing industry will still be the main engine of the economic growth,and therefore our country should make an effective low-carbon policy,introduce advanced technology,increase R&D investment into lowcarbon technologies,and upgrade and transform the original equipment to change the backward mode of production.     

Levels and major sources of PM2.5 and PM10 in Bangkok Metropolitan Region

This research was the first long-term attempt to concurrently measure and identify major sources of both PM₁₀ and PM_2.5 in Bangkok Metropolitan Region (BMR). Ambient PM₁₀ and PM_2.5 were evaluated at four monitoring stations and analyzed for elemental compositions, water-soluble ions, and total carbon during February 2002–January 2003. Fifteen chemical elements, four water-soluble ions, and total carbon were analyzed to assist major source identification by a receptor model approach, known as chemical mass balance. PM₁₀ and PM_2.5 were significantly different (p < 0.05) at all sites and 24 h averages were high at traffic location while two separated residential sites were similar. Seasonal difference of PM₁₀ and PM_2.5 concentrations was distinct between dry and wet seasons. Major source of PM₁₀ at the traffic site indicated that automobile emissions and biomass burning-related sources contributed approximately 33% each. Automobiles contributed approximately 39 and 22% of PM₁₀ mass at two residential sites while biomass burning contributed about 36 and 28%. PM₁₀ from re-suspended soil and cooking sources accounted for 10 to 15% at a residential site. Major sources of PM_2.5 at traffic site were automobile and biomass burning, contributing approximately 32 and 26%, respectively. Biomass burning was the major source of PM_2.5 mass concentrations at residential sites. Meat cooking also accounted for 31% of PM_2.5 mass at a low impact site. Automobile, biomass burning, and road dust were less significant, contributed 10, 6, and 5%, respectively. Major sources identification at some location had difficulty to achieve performance criteria due to limited source profiles. Improved in characterize other sources profiles will help local authority to better air quality.     

Buffer capacity of seawater at high pCO2

Measurements of the variation of the carbon dioxide partial pressure in water were performed up to pCO₂ and CO₂ using 6.000 ppm. The consistent data so far obtained were compared with calculated pCO₂ using the Lynan constants. A plot of the experimental and calculated data evidences that comparisons are only possible by using varying carbonate alkalinity.     

Effect of cigarette smoking on residential NO2 levels

Two studies evaluating the levels and sources of nitrogen dioxide in approximately 90 employee homes in the Richmond area with continuous sampling during the weeks of August 5, 1980, and February 9, 1981, were performed using samplers in the living room, bedroom, kitchen, and outdoors. Additional data were collected concerning appliance usage, heating/cooling plant, ventilation and cigarette smoking. Results were analyzed using BMDP routines. The largest contributor to NO₂ concentration was found to be gas-fired kitchen appliances. The mean kitchen level for homes with gas appliances during the winter study was 188 μg/m³. Excluding participants with gas kitchens, incremental influence due to cigarette smoking was detected. The 7-day, 3-room average level of NO₂ in the homes of nonsmokers and smokers without gas-fired appliances was 12 and 15 μg/m³, respectively, in the summer. The corresponding winter values were 19 and 22 μg/m³. Furthermore, the individual levels of NO₂ in the homes of smokers were generally below both the adjacent outdoor level and the National Ambient Air Quality Standard limit for annual exposure.     

Radon, helium and CO2 measurements in soils overlying a former exploited oilfield, Pechelbronn district, Bas-Rhin, France

The Pechelbronn oilfield (Rhine Graben, France), where mining activity ended in the 1960s, has been used for waste disposal for twenty years. Since the wastes are varied, work is underway to identify the discharged materials and their derivatives, as well as to locate and quantify potential discharge sites. Two major goals were assigned to the present work. The first was to identify or refine the location of hidden structures that could facilitate gas emanation up to the surface, by studying soil gas concentrations (mainly ²²²Rn, CO₂, CH₄ and helium) and carbon isotope ratios in the CO₂ phase. The second was devoted to examining, from a health and safety viewpoint, if the use of the oilfield as a waste disposal site might have led to enhanced or modified gas emanation throughout the area.It appeared that CO₂ and ²²²Rn evolution in the whole area were similar, except near some of the faults and fractures that are known through surface mapping and underground observations. These ²²²Rn and CO₂ anomalies made it possible to highlight more emissive zones that are either related to main faults or to secondary fractures acting as migration pathways. In that sense, the CO₂ phase can be used to evaluate ²²²Rn activities distant from tectonic structures but can lead to erroneous evaluations near to gas migration pathways. Dumping of wastes, as well as oil residues, did not appear to have a strong influence on soil gaseous species and emanation. Similarly, enhanced gas migration due to underground galleries and exploitation wells has not been established. Carbon isotope ratios suggested a balance of biological phenomena, despite the high CO₂ contents reached. Other monitored gaseous species (N₂, Ar, H₂ and alkanes), when detected, always showed amounts close to those found subsurface and/or in atmospheric gases.     

CO2 dispersion around two PWR nuclear power plants in Brazil

Atmospheric air samples were taken within 3 km from power plants encompassing five different distances and wind directions. Samples were taken between 2002 and 2005 aiming to evaluate the environmental ¹⁴C enrichment due to the operation of Brazilian nuclear power plants. The sampling system consisted of a pump connected to a trapping column filled with a 3 M NaOH solution. The trapped CO₂ was analyzed for ¹⁴C by using a single stage accelerator mass spectrometry (SSAMS).     

Climate change from fossil fuel generated CO2 and energy policy

Projections of the magnitude of global climatic change from combustion generated CO₂ are both uncertain and controversial, due in large measure to ignorance of the physical mechanisms involved. Analysis indicates that the uncertainties can be considerably narrowed by considering only the most immediate time frame of possible climatic impact, thereby leading to the possibility of rationally assessing the scope of the threat and the need for remedial action.     

Box models for the CO2 cycle of the earth

Box models for the global CO₂-cycle are described by a system of first order linear differential equations with constant coefficients. Conditions for uniquely existing equilibrium states are given and the reaction to disturbances is analysed. Kalman filtering techniques are applied to uncertainty problems. Some numerical calculations are presented for illustration purposes.     

Can forest policy contribute to solving the CO2 problem?

The steady rise of atmospheric carbon dioxide concentration is due to the combined effects of fossil fuel burning and large scale deforestation. World-wide large scale reforestation could provide, within 15–20 years, an additional biospheric sink of the order of magnitude of the present input. Its capacity would be limited to a time span of several decades, but this time could be used to develop and deploy altenative energy sources (solar, geothermal and others) which presently are unavailable for immediate large scale use.     

Global Research Trends Related to CO2 Emissions and Their Enlightenment to China

Given the growing awareness of the likely catastrophic impacts of climate change and close association of climate change with global emissions of greenhouse gases (of which carbon dioxide is more prominent) , considerable research efforts have been devoted to the analysis of carbon dioxide (CO2) emissions and its relationship to sustainable development. Now GHG reduction programs have been coming into effect in many developed countries that have more responsibility for historical CO2 emissions, and the studies have become mature. First, the GHG emissions accounting system is more all-inclusive and the methods are more rational with the effort of IPCC from 1995 and all other researchers related. Second, the responsibility allocation is more rational and fair. Along with the clarity of "carbon transfer" and "carbon leakage", the perspective and methodology for allocating regional CO2 emissions responsibility is turning from production base to consumption base. Third, the decomposition method has become more mature and more complex. For example, the decomposition formulas are including KAYA expression and input-output expression and the decomposition techniques are developed from index analysis to simple average divisia and then adaptive-weighting divisia. Fourth, projection models have become more integrated and long-term. The top-down model and bottom-up model are both inter-embedded and synergetic. Trends above give some advice for the research on CO2 in China, such as emissions factors database construction, deeper-going research on emissions responsibility and structure analysis, promotion of modeling technology and technology-environment database.     

Aluminum, iron, and lead content of respirable particulate samples from a personal monitoring study

Samples of respirable particulate matter collected during a personal monitoring study in Topeka, KS, were analyzed for iron, aluminum, and lead content. The sampling protocol and instrumentation are described in detail. Lead indoor concentrations (median = 79 ng/m³) were found to be less than both personal (median = 112 ng/m³) and outdoor lead concentrations (median = 106 ng/m³). The indoor, outdoor, and personal levels of iron and aluminum were not significantly different. In addition, it was determined that outdoor respirable particulate mass does not correlate well with the personal or indoor metal concentrations, and that the amount of time spent in motor vehicles is a relatively good indicator of lead exposures. The relationships between indoor, outdoor, and personal lead are discussed in greater detail, with references to supporting evidence from other studies.     

Distributional 234,238U, 226Ra, 210Pb and 210Po in soil

A soil profile from 0 to 90 cm was collected in an undisturbeded area of Cape Cod, Massachusetts. Five centimeter increments of the profile were analyzed for ^234,238U, ²²⁶Ra, ²¹⁰Pb and ²¹⁰Po. The factors affecting the activity distribution of these naturally-occurring radionuclides are discussed for this particular soil type.     

Variations of anthropogenic CO2 in urban area deduced by radiocarbon concentration in modern tree rings

Radiocarbon concentration in the atmosphere is significantly lower in areas where man-made emissions of carbon dioxide occur. This phenomenon is known as Suess effect, and is caused by the contamination of clean air with non-radioactive carbon from fossil fuel combustion. The effect is more strongly observed in industrial and densely populated urban areas. Measurements of carbon isotope concentrations in a study area can be compared to those from areas of clear air in order to estimate the amount of carbon dioxide emission from fossil fuel combustion by using a simple mathematical model. This can be calculated using the simple mathematical model. The result of the mathematical model followed in this study suggests that the use of annual rings of trees to obtain the secular variations of ¹⁴C concentration of atmospheric CO₂ can be useful and efficient for environmental monitoring and modeling of the carbon distribution in local scale.     

Impact of increasing atmospheric CO2 concentrations on global climate: Potential consequences and corrective measures

The increase in the concentration of CO₂ in the atmosphere is closely related to man's activities. There is much concern that this increase might be a major factor contributing to global climatic change. This review analyses the potential climatic impact of these increasing CO₂ concentrations, discusses the potential consequences of the resulting climatic changes, and presents possible solutions to the CO₂ problem.