World Polarization in carbon emissions, potential conflict and groups: an updated revision

Typically, conflicts in world environmental negotiations are related, amongst other aspects, to the level of polarization of the countries in groups with conflicting interests. Given the predictable relationship between polarization and conflict, it would seem logical to evaluate the degree to which the distribution of countries – for example, in terms of their CO2 emissions per capita – would be structured through groups which in themselves are antagonistic, as well as their evolution over time. This paper takes the concept of polarization to explore this distribution for the period 1992-2010, looking at different analytic approaches related to the concept. Specifically, it makes a comparative evaluation of the results associated with endogenous multi-polarization measures (i.e. EGR and DER indices), exogenous measures (i.e. Z-K or multidimensional index) and strict bipolarization measures (i.e. Wolfson’s measure). Indeed, the interest lies not only in evaluating the global situation of polarization by comparing the different approaches and their temporal patterns, but also in examining the explanatory capacity of the different proxy groups used as a possible reference for designing global environmental policy from a group premise. JEL codes: D39; Q43; Q56. Key words: polarization; carbon emissions; conflict;

CO2 utilization in the perspective of industrial ecology, an overview

Carbon dioxide emissions from anthropic activities have accumulated in the atmosphere in excess of 800 Gigatons since preindustrial times, and are continuously increasing. Among other strategies, CO2 capture and storage is one option to mitigate the emissions from large point sources. In addition, carbon dioxide extraction from ambient air is assessed to reduce the atmospheric concentration of CO2. Both direct and indirect (through photosynthesis) pathways are possible. Geological sequestration has significant disadvantages (high cost, low public acceptance, long term uncertainty) whereas carbon dioxide recycling (or utilization) is more consistent with the basic principle of industrial ecology, almost closing material cycles. In this article, a series of technologies for CO2 capture and valorization is described as integrated and optimized pathways. This integration increases the environmental and economic benefits of each technology. Depending on the source of carbon dioxide, appropriate capture and valorization processes are evaluated based on material and energy constraints.

Determinação dos hidrocarbonetos saturados e policíclicos aromáticos presentes no material particulado da atmosfera amazônica

It was identified and quantified several organic compounds in the atmosphere of a site into Amazon Basin with high impact of biomass burning emission. It was important to know the particulate matter composition with respect to n-alkanes and PAH associated with the particulate matter because they provided indication on the main sources contributing to airborne particles, the contribution of natural vs. man-made emission and the aging of the particles. The main classes of compounds observed were n-alkanes, PAH and nitro-PAH. It was observed the formation of nitro-PAH from photochemical reactions. The aerosol mass concentration is mainly associated with fluoranthene, pyrene and benzo(ghi)perylene. Environmental and direct emissions samples (flaming and smoldering) were collected and analysed.

Fontes, reatividade e quantificação de metanol e etanol na atmosfera

In the last two decades, the use of oxygenated fuels, like methanol and ethanol, pure or in mixture with gasoline, has been growing due to benefits introduced into the air quality. In Brasil, the fraction of light duty vehicles powered by pure hydrated ethanol is estimated at about 4 million, while the remaining vehicles actually utilize a mixture (22:78 v/v) of ethanol:gasoline. As a consequence, there's a need for the availability of methods that can provide the evaluation of possible impacts of alcohol emissions in the formation of chemical species in the atmosphere, as ozone, aldehydes, carboxylic acids and so on. In this paper, methanol and ethanol are discussed in their general aspects, as well as their atmospheric sources, chemical reactivity and available methods of analysis.

Avaluació de les emissions de gasos d’ efecte hivernacle a la ciutat de Girona i propostes de reeducació

En els últims 30 anys, la comunitat internacional ha anat agafant consciència dels efectes que pot tenir l’ increment de les emissions de gasos d’ efecte hivernacle (GEH). És per aquest motiu, entre d’ altres que es fan inventaris d’ emissions de GEH a nivell estatal i a gran escala. Aquest projecte té com a principal objectiu determinar i quantificar les emissions de GEH a escala local del municipi de Girona. Per tal de poder dur a terme aquest treball ha calgut buscar metodologies i softwares, que s’ han hagut d’ adaptar a la singularitat que té Girona, sobretot pel que fa al transport. Finalment es fan propostes que s’ adapten a la problemàtica del municipi

Simulating fuel consumption and vehicle emissions in an Australian context

Road transport is a major source of air pollution and greenhouse gas emissions around the world. There is an increasing interest in accurate information on local vehicle emission levels for policy development and sustainable traffic management. Previous studies have shown that emission predictions for the Australian situation need to reflect both the Australian fleet and driving behaviour to avoid unreliable outcomes. This paper discusses a new Australian vehicle emission software (PΔP) and a case-study where traffic simulation software (Aimsun) is combined with PΔP to demonstrate how consistent results can be achieved for the Australian situation. The case-study is an Australian city modelled using the microscopic simulator to generate the required trajectory data of each individual vehicle for the emission model. The simulation results are used in a number of ways: to assess the impacts of urban driving behaviour on fuel consumption, to create maps showing where and when elevated emission levels occur and to compare results with another program (COPERT Australia). The paper will also discuss where further research is required.

Reações de ozonólise de olefinas em fase gasosa

Biogenic emissions of volatile organic compounds play a fundamental role in the atmospheric chemistry, vegetation being one of their major sources. Amongst the VOCs emitted by plants, olefins and terpenoids are the most abundant. These compounds, due to the presence of two or more double bonds and other structural features, are very reactive in the atmosphere and act as precursors of the photochemical smog and aerosols. This article presents a review of the reactions of olefins and terpenoids with ozone, in the gas phase, with emphasis toward the mechanisms and kinetic aspects.

Origem e implicações dos ácidos carboxílicos na atmosfera

A general overview about the ambient levels of low molecular weight carboxylic acids and their possible emission sources, as well as the implication of them in the atmosphere is presented. Carboxylic acids are considered to be one of the dominant classes of organic compounds found in the atmosphere in a variety of phases, such as in rainwater, snow and ice, on aerosol particles and gas phase. They may be originated from biogenic and anthropogenic direct emissions and by photochemical reaction in situ. Emission sources and formation mechanisms of organic acids in the atmosphere are discussed.

Química atmosférica do enxofre (IV): emissões, reações em fase aquosa e impacto ambiental

The oxidation process of sulfur(IV) species by oxygen, ozone and nitrogen oxides, catalysed by trace metal ions, can play an important role in atmospheric chemistry processes like acid rain, visibility degradation and health hazard. An overview of the more relevant investigations on emissions sources, aqueous phase conversion process and environmental impact is presented.

Análises seqüenciais de agrupamentos aplicadas ao estudo de partículas atmosféricas

The present paper has as objective to apply a sequential Cluster Analysis to the atmospheric particles: Hierarchical Cluster Analysis followed by Nonhierarchical Cluster Analysis. The hierarchical cluster analysis results were used as start point for the nonhierarchical cluster analysis as an agglomerative technique. These particles were taken from two areas of the metropolitan region of Porto Alegre, Charqueadas and Sapucaia do Sul., from may /97 to may/98, using a High Volume Sampler (Hi-Vol). Around 10,000 particles were analysed by Scanning Electron Microscope with Energy-Dispersive X-Ray microanalysis (SEM-EDS). The Hierarchical Cluster Analysis allowed the identification of five groups of particles, whose amounts were differentiated according to the summer and the winter campaigns. The abundance of each type of particles inside each group according to the different sections was verified by the Nonhierarchical Cluster Analysis, resulting in information about the emissions sources. The groups of particles of Si/Al and Si and of Fe/Zn and Fe for Charqueadas were more significant in section 2 and 3 (NW and W wind directions) and in section 1 (SE wind direction), evidencing the influence of the coal power plant and steel industry, respectively located in these quadrants. In Sapucaia do Sul the data were more heterogeneous, causing a certain difficulty to identify the source as anthropogenic. Nevertheless the group of particles containing Fe was found in sectors of NW/W wind directions which shows the influence of the steel plant.

Carbono do solo e a mitigação da mudança climática global

The soils of the world contain more carbon than the combined total amounts occurring in vegetation and the atmosphere. Hence soils are a major reservoir of carbon in terrestrial ecosystems and an important sink. Recently, emphasis has been placed on the need to sequester carbon from atmospheric carbon dioxide into soil organic matter because of international concerns about greenhouse gas emissions and global climate change. The best strategies to built-up carbon stocks in the soil are basically those that increase the input of organic matter to the soil, and/or decrease the rate of soil organic matter decomposition. Grain crop systems based on soil ploughing and harrowing lead to CO2 emissions combined with tremendous soil losses. In Brazil, no-tillage system was introduced to combat soil erosion by water and this soil management led to the build-up of soil carbon stocks with simultaneous high crop yields. However, the present procedure used to quantify carbon stocks in soils is laborious and of high cost. The use of infrared spectroscopy is very promising as an alternative low-cost method of soil carbon determination.

Balancing effluent quality, economic cost and greenhouse gas emissions during the evaluation of (plant-wide) control/operational strategies in WWTPs

The objective of this paper was to show the potential additional insight that result from adding greenhouse gas (GHG) emissions to plant performance evaluation criteria, such as effluent quality (EQI) and operational cost (OCI) indices, when evaluating (plant-wide) control/operational strategies in wastewater treatment plants (WWTPs). The proposed GHG evaluation is based on a set of comprehensive dynamic models that estimate the most significant potential on-site and off-site sources of CO2, CH4 and N2O. The study calculates and discusses the changes in EQI, OCI and the emission of GHGs as a consequence of varying the following four process variables: (i) the set point of aeration control in the activated sludge section; (ii) the removal efficiency of total suspended solids (TSS) in the primary clarifier; (iii) the temperature in the anaerobic digester; and (iv) the control of the flow of anaerobic digester supernatants coming from sludge treatment. Based upon the assumptions built into the model structures, simulation results highlight the potential undesirable effects of increased GHG production when carrying out local energy optimization of the aeration system in the activated sludge section and energy recovery from the AD. Although off-site CO2 emissions may decrease, the effect is counterbalanced by increased N2O emissions, especially since N2O has a 300-fold stronger greenhouse effect than CO2. The reported results emphasize the importance and usefulness of using multiple evaluation criteria to compare and evaluate (plant-wide) control strategies in a WWTP for more informed operational decision making

Analytical investigation of the atmospheric radiation limits in semigray atmospheres in radiative equilibrium

We model the wavelength-dependent absorption of atmospheric gases by assuming constant mass absorption coefficients in finite-width spectral bands. Such a semigray atmosphere is analytically solved by a discrete ordinate method. The general solution is analyzed for a water vapor saturated atmosphere that also contains a carbon dioxide-like absorbing gas in the infrared. A multiple stable equilibrium with a relative upper limit in the outgoing long-wave radiation is found. Differing from previous radiative–convective models, we find that the amount of carbon dioxide strongly modifies the value of this relative upper limit. This result is also obtained in a gray (i.e., equal absorption of radiation at all infrared wavelengths) water vapor saturated atmosphere. The destabilizing effect of carbon dioxide implies that massive carbon dioxide atmospheres are more likely to reach a runaway greenhouse state than thin carbon dioxide ones

Empirics of the international inequality in CO2 emissions intensity: explanatory factors according to complementary decomposition methodologies

This paper analyses the international inequalities in CO2 emissions intensity for the period 1971- 2009 and assesses explanatory factors. Multiplicative, group and additive methodologies of inequality decomposition are employed. The first allows us to clarify the separated role of the carbonisation index and the energy intensity in the pattern observed for inequalities in CO2 intensities; the second allows us to understand the role of regional groups; and the third allows us to investigate the role of different fossil energy sources (coal, oil and gas). 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.