Terms Of Carbon Dioxide Emissions Research Articles

Carbon dioxide life cycle assessment for Brazilian passenger cars fleet towards 2050

Brazil is the second largest producer of ethanol in the world, losing the first position to the United State of America. Nonetheless, several studies have shown that the sustainability of the ethanol produced from the sugarcane is better than their competitor's wheat, corn, and beet in terms of carbon dioxide emissions, energy rate (input/output), productivity, and energy content. Thus, the different incentives from the government since 1975 to the industry allow it to produce technology capable of using any mix of ethanol hydrous and gasoline in the engines, this also brought several developments to sugarcane productivity. So then, there is a new worldwide transition coming to the world with the focus of reducing carbon dioxide emissions. Therefore, this paperwork assesses the main problems of the sustainability transition from current Brazilian Flex-Fuel Vehicles to electric vehicles, in terms of Law 13.755, ROTA2030 and the National Plan of Energy - 2050. The results show that the best option for Brazil as a country, considering socioeconomic and environmental impacts, is to introduce as a priority the Hybrid Electric Vehicles with a flex-fuel engine and then the Plug-in Hybrid Electric Vehicles with a flex-fuel engine. The last priority for the transition of midsize and full-size vehicles should be the Battery Electric Vehicles.

Recycling Local Waste Glass Bottles into Cement Paste: Effect on Hydration, Microstructure, and CO2 Emission.

Large amounts of waste glass are generated along with the manufacturing of glass products, causing detrimental effects on the environment. Through crushing and ball-milling, waste glass powder (WGP) can be acquired from glass bottles and has been suggested in cementitious systems due to its potential pozzolanic activity. To better understand the impact of WGP on cementitious composites, experimental tests of rheology, heat of hydration, and strength development were conducted on cement pastes with and without WGP. Results show that the rheological performance of cement paste is improved when WGP with particles passing through 80 μm sieves is incorporated. The retarding effect and pozzolanic reaction were observed through X-ray diffraction patterns and thermo-gravimetric parameter analyses. A calcium hydroxide (CH) content calculation further confirms the secondary reactivity of WGP in cement pastes. Compared with the samples without WGP, the normalized CH content of binder per unit mass containing 35% WGP decreased by 21.01%, 24.94%, and 27.41% at the ages of 1, 28, and 90 days, respectively, which contributes to late-age strength development of pastes. At the same time, the hydration per unit of cement was increased by 21.53%, 15.48%, and 11.68%, which improved the cement efficiency. In addition, WGP particles provide nuclei for hydration products, facilitating the subsequent growth of C-S-H and strength development in late ages. Based on value engineering analysis, WGP was found to reduce the impact of Portland cement on the environment by 34.9% in terms of carbon dioxide emissions, indicating a bright prospect for WGP in the cement industry.

Life cycle analysis of biodiesel derived from fresh water microalgae and Karanja

Biodiesel is regarded as a feasible substitute for fossil fuel; thus, to fulfil the tremendous need for energy, potential non-edible feedstocks must be identified and assessed in terms of their environmental consequences and energy requirements for biodiesel production. Cradle to Grave life cycle approach (LCA) is currently being used to compare the environmental impacts and energy requirements of biodiesel obtained from two types of biodiesel feedstock i.e., Karanja (Pongamia Pinnata) and Microalgae. Sensitivity analysis was also performed to explore the influence of elements such as agricultural systems and energy sources on LCA systems in the given conditions. Karanja feedstock and microalgae have energy ratios of 3.57 and 0.45, respectively. GHG emissions from well to wheel for oil methyl esters derived from Karanja feedstock are estimated to be 63.81 gCO2eq/MJ, while microalgae feedstock emissions are 85.37 gCO2eq/MJ. According to the sensitivity study, both emission and energy estimates were significantly sensitive to biodiesel output. Karanja excelled in all GHG-emitting processes, with reduced GHG emissions and a greater energy ratio. Microalgae, on the other hand, would be the preferable feedstock in the long run since it has demonstrated competitive performance in terms of carbon dioxide emissions, and energy ratio, and has no detrimental influence on the food cycle.

The Environmental, Economic and Social Welfare Impacts of the CCREW Project in China: A Study Based on the CGE Model

Countries around the world have carried out digital transformations to improve their economic resilience. As the largest developing country, China put forward the “channeling computing resources from the East to the West (CCREW)” project in 2022 to balance and promote the development of various regions. This paper constructs a three-region computable general equilibrium model covering the eastern, western, and other regions and evaluates the impact of the project on economic development, social welfare, and carbon emissions in different regions. By simulating the transfer share of the CCREW project, this paper attempts to further reveal the impact of the policy both on regional differences and national development. The results show that the effects of the project are quite different among regions. Our findings can be summarized as follows. (1) In terms of carbon dioxide emissions, the policy will cause emissions to shift from the East to the West. (2) In terms of economic development, the policy will lead to an overall downward trend in the GDP of the eastern and other regions, whereas for the western region, the policy will promote the development of the regional economy. Regional differences may affect the implementation of the policy and its effects. (3) In terms of social welfare, the policy will result in an inverted U-shaped change in social welfare at the national level, which first rises and then falls, and will change from positive to negative when the transfer share exceeds 20%. At the regional level, social welfare in the eastern and other regions will decline, whereas that in the western region will show an inverted U-shaped change that first increases and then decreases. (4) In the short term, the project at the national level has reduced carbon emissions at the expense of economic development and incurred a loss in social welfare.

The carbon effects of the evolution of node status in the world trade network

Trade has contributed to economic development and has brought countries or regions of the world closer together, but it has also had a significant impact on the global environment, particularly in terms of carbon dioxide emissions. Does an increase in a country’s trade necessarily contribute to an increase in its carbon emissions? This paper examines the impact of changes in the position of major countries in the world trade network on their carbon emission levels. In terms of research methodology, this paper achieves an innovation by adopting a complex network approach to analyze the structural characteristics of the trade relationship networks of major countries or regions in the world, providing a new perspective for the study of the relationship between trade development and carbon emissions. The results of the study show that: trade relations among countries are relatively stable from 2000 to 2020, trade ties among members of regional integration organizations are increasing, the top ten countries in terms of importance are mainly developed countries, and China has very close trade relations with most countries. Based on the analysis of structural characteristics, the impact of changes in the network status of each country on its ocarbon emissions is analyzed, using indicators such as the degree centrality of each node as the independent variable and its domestic carbon emission level as the dependent variable. It is found that developed countries have a significant positive impact on in-going degree centrality, and insignificant impact on out-going degree centrality and betweenness centrality. In contrast, developing countries have a significant positive impact on out-going degree centrality and a negative impact on carbon emissions by betweenness centrality, and this conclusion tells us that not all export growth will contribute to higher levels of carbon emissions in the country. Eigenvector centrality has a negative effect on carbon emissions for both developing and developed countries, and closeness to centrality has no effect on carbon emissions while closeness centrality has no effect on carbon emissions. The results of this study again show that the influence of developed countries is greater than that of developing countries on carbon emissions; therefore, the role of developed countries can be taken into account in subsequent studies on carbon emission reduction.

Evaluating the Energy Efficiency and Environmental Impact of COVID-19 Vaccines Coolers through New Optimization Indexes: Comparison between Refrigeration Systems Using HFC or Natural Refrigerants

COVID-19 vaccines are used worldwide to promote immunity and, in that sense, vaccination is a step forward toward ending the pandemic. Nevertheless, current vaccines must be ultra-cold or cold-stored. Vaccine coolers’ energy demand and greenhouse gas emissions lead to a significant environmental impact. This article predicts the environmental and energy impacts of some COVID-19 vaccines: Moderna, Janssen, CoronaVac, Pfizer, AstraZeneca–Oxford–Covishield, and Sputnik V, in terms of carbon dioxide emissions using a new approach for the TEWI (Total Equivalent Warming Impact) methodology, with several options of refrigerants from halogenated to natural fluids such as propane, which is natural gas with low GWP (global warming potential). Through the application of new optimization indexes, it is concluded that the evaporation temperature of the refrigerant gas has a great influence on the sizing of the coolers. For example, for the same number of vaccines, the thermal load of Pfizer is more than double that of AstraZeneca–Covishield, CoronaVac, or Janssen, while the direct environmental impact is seven times greater. Another relevant factor is the choice of refrigerant. For example, the greenhouse effect varies greatly for the same brand of vaccine. The Moderna vaccine’s global warming potential (GWP) is 776 times higher using R-449A gas than using R-290 (propane gas). In Brazil, the refrigerators used to store the Pfizer vaccine have a total TEWI almost two times higher than the total TEWI of refrigerators using propane to store the Janssen vaccine. At this time of the pandemic, these optimization indexes can be used to support important decisions regarding the future selection of vaccine brands considering the energy consumption and environmental impact required for their storage.

A new approach to evaluate environmental strategy: Empirical evidence from international petroleum companies using the balanced scorecard model

AbstractThe core of this study is to empirically evaluate the environmental strategy in terms of carbon dioxide emissions (CO2) from the perspectives of both managers and investors. The study incorporates the Porter hypothesis and the balanced scorecard (BSC) assumptions to analyze data from 17 international petroleum companies for the period 2005q1–2016q4 by linking the strategy map and BSC to the actual key performance indicators (KPIs). Panel dynamic regression analysis is employed to evaluate the said strategy for both the short and the long terms. The results clearly indicate that the environmental strategy has a significant and positive impact on the environmental performance not only in the short term but also in the long term. This study contributes to the BSC studies on this topic by presenting a perspective of the strategy in the form of a mathematical model that can be statistically testable for both the short and the long terms, thereby providing a guideline to managers for strategy evaluation purposes, optimization of resource allocation, and improvements in both the environmental and financial performances in the long term.

Multidisciplinary conceptual design for a hybrid-electric commuter aircraft

AbstractThe electrification of the commuter aircraft is instrumental in the development of novel propulsion systems. The scope of this work aims to explore the design space of a parallel hybrid-electric configuration with an entry into service date of 2030 and beyond and determine the impact of other disciplines on conceptual design, such as components positioning, aircraft stability and structural integrity. Three levels of conceptual sizing are applied and linked with a parametric aircraft geometry tool, to generate the aircraft’s geometry and position the components. Subsequently, the structural optimisation of the wing box is performed, providing the centre of gravity of the components placed inside the wing, that minimise the induced stresses. Furthermore, the stability and trim analysis follow, with the former being highly affected by the positioning of components. Results are compared to a similar aircraft with entry into service technology of 2014 and it is indicated that in terms of block fuel reduction the total electrification benefit increases with the increase of degree of hybridisation, if aircraft mass is kept constant. On the other hand, if battery specific energy is kept constant, similar block fuel reduction is possible with lower hybridisation degrees. The potential for improvement in terms of carbon dioxide emissions and block fuel reduction ranges from 15.73% to 21.44% compared to the conventional aircraft, for levels of battery specific energy of 0.92 and 1.14 kWh/kg respectively. Finally, the component positioning evaluation indicates a maximum weight limitation of 240 kg for the addition of an aft boundary layer ingestion fan to a tube and wing aircraft configuration, without compromising the aircraft static stability.

A comparative LCA study of passive cooling roof materials for a residential building: An Indian Case study

Construction industry is a significant contributor to global environmental impact, with large amount of energy being utilized in the production and transportation processes of various building materials. Energy conservation in buildings becomes a critical factor in reducing the greenhouse emissions and at the same time focusing on reducing the cost of materials. By using digital tools of Life Cycle Analysis (LCA) and Building Information Modelling (BIM) techniques, the ecological collisions can be measured and lowered through analysis of alternative eco-friendly materials. In this study, a BIM-based LCA was carried out for a case study residential building to be constructed with conventional materials, located in the warm-humid climate region of India. The findings revealed that roof slab constructed with reinforced concrete is contributing more carbon dioxide equivalent (CO2e) next to vertical facade in terms of environmental impacts, energy consumptions and global warming potential. An analytical study was performed on alternative building materials with walls being replaced with AAC blocks and roof slab with clay tiles, cool tiles, terrazzo tiles as insulation layers. The roofs and walls replaced with alternate materials showed 2–6% reduction in terms of carbon dioxide emissions, acidification, eutrophication, and ozone depletion potentials.

Incineration problems for the heat supply using garbage from the overproduction of fast fashion clothing

Today, one of the sources of energy supply is waste incineration. One of the sources of combustible waste is overproduction and stimulation of demand for clothing. The new concept of "fast fashion" is to limit the cost of clothing indefinitely by minimizing the cost of raw materials, wages, working conditions, neglect of basic safety rules, etc., and on the other hand - to stimulate predatory demand for clothing through psychological impact on young people through advertising, suggestion consumer "standards" of life such as "every event is a different image", propaganda of shopaholism, etc. According to research results, burning cotton clothes for heating is possible. However, this produces a significant amount of triatomic (greenhouse) gases, in particular carbon dioxide 102.84 kg / GJ. In terms of carbon dioxide emissions per unit of energy (emission index), cotton fabric is ahead of all fossil fuels, even coal - 93.74 kg / GJ. Thus, excessive production of garbage through "fast fashion" has more negative consequences for the environment than benefits for heat supply. Thus, the results confirm the 12th goal of sustainable development - "responsible consumption and production". At the same time, the priority is to reduce the amount of waste production. The main stimulus for "fast fashion" is the predatory accumulation of capital by producers. This can be overcome only by reassessing people's values. In particular, it is necessary to form the attitude to money not as an ultimate goal, but as a payment instrument to achieve certain other life goals. In this case, predatory accumulation for the sake of accumulation becomes meaningless. After all, one's own well-being, children's well-being and confidence in the future are impossible in the conditions of low quality of the environment and in anticipation of an ecological catastrophe. This work was done in support of the international campaign "Fashion Revolution" for the global fashion industry, which preserves and restores the environment and values people.

Prospective Electric Power Cooperation among Northeast Asian Countries in the Context of Carbon Tax Sergei Podkovalnikov, Chudinova Lyudmila

The paper addresses the prospects for power grid formation in Northeast Asia in terms of carbon dioxide emissions. Carbon dioxide tax is implemented as a tool to quantitatively engage environmental issues in the study. A survey of the studies on the prospective NEA power grid has been done. The research employs a methodology and a mathematical model for the optimization of power system expansion and economic dispatching of power plants. Environmentally friendly scenarios of the NEA power grid were built and studied.

Water-energy nexus: A thermoeconomic analysis of polygeneration systems for small Mediterranean islands

This paper focuses on the energy-water nexus, aiming at developing novel systems producing simultaneously energy and water. This work investigates two solar polygeneration plants for the production of thermal and cooling energy, electricity, and desalinated water for two small Mediterranean islands. In this case, seawater and solar energy are largely available, whereas freshwater is scarce and extremely expensive. The work also aims to compare different technologies included in the polygeneration systems. In particular, the first plant is based on concentrating photovoltaic/thermal solar collectors, producing electric and thermal energy. The thermal energy is used to produce space heating, domestic hot water and space cooling by means a single-stage Lithium Bromide/Water absorption chiller. An electric auxiliary chiller is also included. A multi-effect distillation unit is included for freshwater production supplied by the concentrating photovoltaic/thermal collectors solar energy and an auxiliary biomass-fired heater. In the second plant, a photovoltaic field is coupled with electric driven technologies, such as heat pumps for space heating, cooling and domestic hot water production and a reverse osmosis unit. The solar electrical energy excess is delivered to the grid. The third polygeneration plant includes the same components as the first layout but it is equipped with a reverse osmosis unit. Two main case studies, Favignana and Salina islands (South Italy) are selected. The heating, cooling and electric hourly loads of some buildings located in both investigated weather zones are calculated in detail. In particular, space heating and cooling loads are calculated by means of the Type 56 of TRNSYS (version 17), coupled to the Google SketchUp TRNSYS3d plug-in. The buildings geometry, envelope, windows, lighting, machineries heat gains schedule, as well as the buildings users’ occupation and activity are simulated by means of the Type 56. TRNSYS is also used to accurately model all of the plant components. The work also includes comprehensive energy, environmental and economic analyses to maximize the plants profitability, evaluated by considering both operating and capital costs. Sensitivity analyses aiming at establishing the optimal values of the most important design parameters are also performed. The developed plants achieve important savings in terms of carbon dioxide emissions due to the use of renewable energy sources and the high efficiency of the included technologies. The best economic indexes are obtained for the layout using electricity-driven technologies, resulting in very profitable operation with a payback period of about 6.2 years.

Environmental and Economic Life Cycle Analysis of Primary Construction Materials Sourcing Under Geopolitical Uncertainties: A Case Study of Qatar

Environmental and economic cycles under varying geopolitical uncertainties can lead to unsustainable patterns that significantly and negatively affect the welfare of nations. With the ever-increasing negative environmental and economic impacts, the ability to achieve sustainability is hindered if the implications are not properly assessed in challenging geopolitical crises. The infrequent and fluctuating nature of these challenging geopolitical settings causes disregard and neglect for exploration within this issue. In this study, a comparative life cycle assessment was conducted as a method to evaluate the environmental and economic impacts of construction material flow across country boundaries. Based on the results found from the life cycle assessment, an environmental forecast and sensitivity analysis were established. Considering the State of Qatar as a case study, asphalt and bitumen, cement, limestone, sand, and steel were analyzed from gate-to-gate depending on transportation mode and distances used within both the pre-crisis and post-crisis sub-periods, comparing carbon emissions and costs. The results showed that the mode of transport plays a significant role in terms of carbon dioxide emissions as opposed to distance traveled. However, the increase in distance coupled to the majority shift from land to sea-based transport resulted in an overall increase in carbon emissions and costs post-crisis. In addition, the analysis of the environmental and economic impact assessment using the average CO2 equivalent (CO2-e) per kilogram and the unit price of the five primary construction materials has shown a significant, 70.68% increase in global warming potentials (GWP) after the crisis, coupled with an increase in the overall cost. An assessment of environmental and economic impacts during geopolitical uncertainties allows for the significant ability to realize sustainable measures to greatly reduce economic and environmental degradation.

CSA and slag: towards CSA composite binders

Green binders, eco-friendly cementitious materials, low embedded carbon dioxide cements: different names for products aimed at reducing the environmental impact of cement production. Calcium sulfoaluminate (CSA) cements offer a valid alternative to ordinary Portland cement (OPC) since they couple the advantages of a lower environmental impact during production with high early-age performance and dimensional stability. Their use is now increasing due to the development of dedicated standard processes. The combination of CSA cement with OPC has been widely investigated and a few products have been developed and are already available on the market. Supplementary cementitious materials (SCMs) are widely used to improve the durability performance and lower the clinker content. High levels of substitution have allowed for improvements of performance indicators in terms of carbon dioxide emissions, but mechanical strengths at early ages can be affected. The combination of sulfoaluminate cement, OPC and SCMs opens the route towards innovative composite binders that offer good mechanical performance and significant reductions in carbon dioxide emissions.

Multi-objective optimization of district heating and cooling systems for a one-year time horizon

Besides lowering supply temperatures, the concept of fourth generation of district heating (4DH) also includes integration of heating, cooling and power sector. Due to their high interconnectivity, number of involved technologies and relatively long, but at the same time detailed temporal scale, optimization of such systems presents a challenging task. So far, only hourly district heating multi-objective optimization for a whole year period has been carried out, where detailed district heating and cooling multi-objective optimization has been reserved for small scale utilization and short temporal scale, usually covering specific days or weeks. The main objective of this paper was to develop an hourly based multi-objective optimization district heating and cooling model which is capable of defining supply capacities, including thermal storage size, and their operation for a whole year period. The objective functions are minimization of a total system cost, which includes discounted investment and operational costs, and minimization of environmental impact in terms of carbon dioxide emissions. By using multi-objective optimization, this research shows that for equal level of carbon dioxide emissions, combined district heating and cooling systems have lower total discounted cost when compared to district heating and cooling systems which operate separately.

Significance of Concrete Production in Terms of Carbondioxide Emissions: Social and Environmental Impacts

Concrete is being recognized for its strong environmental benefits in support of creative and effective sustainable development. In response to growing environmental and economic forces, regulatories, engineers, developers and owners are seeking efficient, innovative solutions that conserve non-renewable resources. When considering the lifetime environmental impact of a building material -extraction, production, construction, operation, demolition and recycling- is the most advantageous choice to meet these goals. Global demands for regulating production waste arise from the growth of these environmental and economic issues. Various efforts have been conducted by researchers to arrive at some alternatives that are able to significantly reduce high energy consumed and environmental impacts during fabrication process of cement. Therefore, the concept of green concrete as an environmentally friendly alternative to conventional has been emerging. This publication seeks to demonstrate how contributes to future generations’ sustainable development, and will be of interest to architects, engineers, policy makers, contractors and clients, as well as others involved with the design, construction or operation of buildings and infrastructure. The main objective of this study is to identify and evaluate the key sources contributing to CO 2 emissions from and compare traditional concretes with “green concretes”, concretes produced with blended cements and fly ash used as partial replacement of cement, in order to diminish the environmental impact of the production.

Внутренние и глобальные проблемы в экологической политике Китая

The problem of climate change in the last few years has become one of the most popular in thenational discourses of the country as China’s.In declarations and documents around the world, the climatic changes which are connected withgreenhouse gas emission are associated with economic development of PRC. The People’s Republic ofChina is a major energy importer, thereby having its impact on the reserves of world’s natural resources.Economic development and environmental degradation in China affect the inhabitants of othercountries as well. Joint international efforts are required to solve transboundary and global environmentalproblems. Nowadays, China is a party to major international agreements in the field of environmentand development, is an active participant in international conferences, and also China collaborates onissues of environment and development with many countries of the world. China currently ranks firstin terms of carbon dioxide emissions. In conditions of intensive industrial development, the country inrecent decades is experiencing significant environmental consequences of man-made activities. China’sdesire to implement its economic and political goals is in contradiction with the environmental conditionsof life of the population. Over the past two decades, the economic boom in China has caused anincrease in consumption and significantly worsened the environmental quality of life. The country needsmore and more natural resources, energy consumption is steadily growing. Nevertheless, China seeksand finances scientific developments in the field of new technologies that promote the implementationof the adopted environmental laws and initiatives.Key words: China, globalization, ecology, environment, climate change, eco-policy, ecosystem,sustainable development.

Results of assessing СО2 emissions from e-vehicles in case of their possible switching to electricity

Abstract The article provides an assessment of e-vehicles operation safety in terms of carbon dioxide emissions to the atmosphere, and analysis of electrified vehicles’ development trends in various countries. Engineering capabilities of vehicle electrification in Russia are addressed. It is determined that the share of the environmental impact of pollutant emissions upon fuel combustion by the entire fleet of vehicles amounts to 15–20% of the total volume of pollutant emissions to the atmosphere from all sources. Various types of power stations are compared by greenhouse gas emissions. It is concluded that most power stations emit significant volumes of СО2. Greenhouse gas emissions from petrol vehicles and e-vehicles are compared with account for the environmental impact of power generation and petrol production technologies. According to the assessment, electrification of vehicles will not result in reduced greenhouse gas emissions on the global scale. On the contrary, СО2 emissions can increase. The authors suggest to launch the program in a particular region of Russia, taking into account its geographic, climatic and infrastructure power resources, in order to obtain an environmental effect from the widespread use of e-vehicles.

Time-dependent green Weber problem

We consider an extension of the classical Weber problem, named as the green Weber problem (GWP), in which the customers have one-sided time windows. The GWP decides on the location of the single facility in the plane and the speeds of the vehicles serving the customers from the facility within the one-sided time windows so as to minimize the total amount of carbon dioxide emitted in the whole distribution system. We also introduce time-dependent congestion which limits the vehicle speeds in different time periods and call the resulting problem as the time-dependent green Weber problem (TD-GWP). In the TD-GWP, the vehicles are allowed to wait during more congested time periods. We formulate the GWP and TD-GWP as second order cone programming problems both of which can be efficiently solved to optimality. We show that if the traffic congestion is non-increasing, then there exists an optimal solution in which the vehicles do not wait at all. Computational results are provided comparing the locations of the facility and the resulting carbon dioxide emissions of the classical Weber problem with those of the GWP and comparing the GWP with the TD-GWP in terms of carbon dioxide emissions in different traffic congestion patterns.

Quantitative relationships between investments in farms and environmental effects in some European countries

Since the early 1970s, in many European Union member countries, there has been a significant improvement in their own agricultural economic growth due to the Common Agricultural Policy. The increasing levels of investment in land and in machinery have been one of the pivotal pillars in improvement levels of food self-sufficiency. However, a growth in investments has increased pollutant emission in terms of carbon dioxide, nitrogenous compounds and a deterioration of an environment. The purpose of this paper was to investigate the impact of investments on agricultural and arable land in improving agricultural production towards environmental quality. The quantitative methods have used a neural relation analysis through the Kohonen?s maps or self-organizing maps (SOMs). Findings of Kohonen?s maps have pointed out a good ability to classify the time series data and the spatial evolution of data over the time; furthermore, SOMs have been useful in describing the impact of investment on production specialization, levels of pollution and food self-sufficiency in the European countries. To sum up, an improvement of food self-sufficient levels has been tightly linked to an increase of pollution in terms of carbon dioxide emissions.