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This paper investigates overall CO2 balances of combined heat and power (CHP) plants with CO2 capture and storage (CCS) in Kraft pulp and paper mills. The CHP plants use biomass-based fuels and feature advanced gasification and combined cycle technology. Results from simple process simulations of the considered CHP plants are presented. Based on those results and taking into account the major direct and indirect changes in CO2 emissions, the study shows that implementing CCS leads to steep emission reductions. Furthermore, a preliminary cost assessment is carried out to analyse the CO2 mitigation cost and its dependence on the distance that the CO2 must be transported to injection sites. [ABSTRACT FROM AUTHOR]

Forest biomass can be used in two different ways to limit the growth of the atmospheric greenhouse gas (GHG) concentrations: (1) to provide negative emissions through sequestration of carbon into forests and harvested wood products or (2) to avoid GHG emissions through substitution of non-renewable raw materials with wood. We study the trade-offs and synergies between these strategies using three different Finnish national-level forest scenarios between 2015 and 2044 as examples. We demonstrate how GHG emissions change when wood harvest rates are increased. We take into account CO2 and other greenhouse gas flows in the forest, the decay rate of harvested wood products and fossil-based CO2 emissions that can be avoided by substituting alternative materials with wood derived from increased harvests. We considered uncertainties of key parameters by using stochastic simulation. According to our results, an increase in harvest rates in Finland increased the total net GHG flow to the atmosphere virtually certainly or very likely, given the uncertainties and time frame considered. This was because the increased biomass-based CO2 and other greenhouse gas emissions to the atmosphere together with decreased carbon sequestration into the forest were very likely higher than the avoided fossil-based CO2 emissions. The reverse of this conclusion would require that compared to what was studied in this paper, the share of long-living wood products in the product mix would be higher, carbon dioxide from bioenergy production would be captured and stored, and reduction in forest carbon equivalent net sink due to wood harvesting would be minimized. [ABSTRACT FROM AUTHOR]

The aim of this paper is to provide a sector-based method for carbon dioxide (CO) emissions control and to disaggregate China's national CO mitigation burden at the sectoral level. Based on a detailed analysis of three burden sharing indicators-responsibility, capacity, and efficiency-this paper derives a mitigation burden index to suggest which economic sectors should bear more (or less) mitigation burden. A multi criteria allocation model of sectoral CO intensity (CO per unit of added value) is then constructed to determine each sector's mitigation target for 2020. The main findings are: (1) Allocation results based on multi criteria are more acceptable and practical than those based on only one criterion. (2) Policy maker preference for criteria has a significant effect on allocation results. (3) The fours sectors, manufacture of raw chemical materials and chemical products, manufacture of non-metallic mineral products, smelting and pressing of ferrous metals, and other services, consistently bear the highest mitigation burden. This paper offers policy makers a sector-based method to control CO emissions. Combining this method with sectoral potential for technological advancement and sectoral mitigation costs would produce a more feasible and cost effective burden sharing scheme. [ABSTRACT FROM AUTHOR]

The use of wood products is often promoted as a climate change mitigation option to reduce atmospheric carbon dioxide concentrations. In previous literature, we identified longevity and recycling rate as two determining factors that influence the carbon stock in wood products, but no studies have predicted the effect of improved wood use on carbon storage over time. In this study, we aimed at evaluating changes in the lifespan and the recycling rate as two options for enhancing carbon stock in wood products for different time horizons. We first explored the behaviour over time of both factors in a theoretical simulation, and then calculated their effect for the European wood sector of the future. The theoretical simulation shows that the carbon stock in wood products increases linearly when increasing the average lifespan of wood products and exponentially when improving the recycling rate. The emissions savings under the current use of wood products in Europe in 2030 were estimated at 57.65 Mt carbon dioxide (CO) per year. This amount could be increased 5 Mt CO if average lifespan increased 19.54 % or if recycling rate increased 20.92 % in 2017. However, the combination of both strategies could increase the emissions saving almost 5 Mt CO more by 2030. Incrementing recycling rate of paper and paperboard is the best short-term strategy (2030) to reduce emissions, but elongating average lifespan of wood-based panels is a better strategy for longer term periods (2046). [ABSTRACT FROM AUTHOR]

Despite the heated debate over the relationship between economic development and carbon dioxide (CO2) emissions, few studies have focused on the impact of spatial relationships between neighboring countries on CO2 emissions. Adopting the World Bank's classification of income levels, this paper classifies 177 countries into four groups and then analyzes the spatial-temporal variations in CO2 emissions. Based on that analysis, the core task of our study is to estimate a carbon Kuznets curve (CKC) from two methods of traditional statistics and spatial econometrics. The main findings indicate that global CO2 emissions have significant spatial clustering characteristics, and the clustering types are closely linked to geographic location and income level. In addition, the existence of standard CKC and spatial CKC were confirmed. Countries with different income levels have different CO2 emission stages, and a country's CO2 emissions are affected both directly by its own economy and indirectly by the economies of its neighbors. In this context, the mitigation and adaptation strategies for CO2 reduction are proposed as follows. (1) Neighboring countries must develop regional cooperative initiatives to reduce CO2 emissions. (2) Clarifying the emission stage of a country is an important basis for policymakers to formulate emission reduction strategies. (3) The economic development and CO2 emissions of neighboring countries are also important factors in formulating emission reduction plans. [ABSTRACT FROM AUTHOR]

With increases in the economy and standards of living, energy consumption has grown significantly in China, which has resulted in serious local air pollution and greenhouse gas emissions. Because both carbon dioxide (CO2) and air pollutant emissions mainly stem from fossil energy use, a co-control strategy is simulated and compared with single control in China, using an integrated assessment model (Global Change Assessment Model-Tsinghua University (GCAM-TU)) in this paper. We find that end-of-pipe (EOP) control measures play an important role in reducing air pollution in the near future, but in the long run, optimizing the energy system is an effective way to control both emissions. Reducing air pollutant might take a "free-ride" of decarbonizing the energy system. Compared with a single control of air pollutants, a co-control strategy is likely to reduce the requirement of EOP control measures. The result guides the Chinese government to consider a systemic and scientific plan for decarbonizing the energy system and co-controlling CO2 and air pollutant, in order to avoid duplicate investments in infrastructure and lockup effect. The solution could be extended to many other developing countries, such as India and Africa, which is helpful to realize the goals of United Nations (UN) Sustainable Development Agenda. [ABSTRACT FROM AUTHOR]

An important development in recent years has been increased interest in retrofitting CO capture at existing power plants. In parallel, it has also been suggested that flexible operation of power plants with CO capture could be important in at least some jurisdictions. It is likely that retrofitted power plants could have significant 'built-in' flexibility, but this potential is often not considered in studies of the economic performance of power plants with CO capture. This paper makes a contribution to filling this gap by developing methods for first order screening analysis of flexible operation of power plants with CO capture and applying them to the case study example of an appropriately integrated retrofit of post-combustion capture at a coal-fired power plant. The quantitative analysis suggests that rich solvent storage could be an attractive option on a short-run basis for some fuel, CO and electricity price combinations. Results from first order analysis can then be used to determine which operating modes should (and shouldn't) be included in further, more detailed design studies. [ABSTRACT FROM AUTHOR]

This paper analyzes the capabilities of a pilot-scale chemical looping combustion plant firing wood biomass in two stages to efficiently achieve negative carbon dioxide emissions. The utilized in situ gasification-chemical looping combustion (iG-CLC) process isolates the oxygen supply via air from the fuel conversion itself with the help of two separate fluidized bed reactors and an oxygen carrier to supply the necessary oxygen for the combustion. As a result, a relatively pure stream of carbon dioxide and steam is generated. Thus, the process makes capturing carbon emissions more feasible since it eliminates the need for the cost- and energy-intensive separation of the produced gases. A major issue when using biomass in a chemical looping plant is the high amount of the volatiles exiting unconverted. This problem was mitigated by using a two-stage fuel reactor system. Two bubbling fluidized beds were arranged one upon the other. The lower stage, where the fuel is introduced, is used to release the volatiles and partly convert them. The remaining volatiles rise up into the second stage and are further converted to a high degree. A series of experiments were carried out with a 25-kWth pilot plant located at the Hamburg University of Technology. Gas concentrations were continuously measured after both stages of the fuel reactor to see the gradual conversion of the fuel gases. Additionally, carbon slip at the exhaust was measured to show the effectiveness. The experiments with the reactor concept showed promising results since already at a reactor temperature of 850 °C, the total oxygen demand needed to oxidize the combustible component in the exhaust gas was well below 2%. The carbon dioxide (CO2) capture efficiency when using German hardwood slightly decreased to 93–96% compared to 97% for German lignite. In the future, the reactor design must prove that it scales and that the efficiency can be further increased. Nevertheless, firing biomass with a two-stage iG-CLC process might allow a cost-efficient negative carbon dioxide emission while generating heat with relatively high efficiency. Therefore, it might be a sustainable alternative to generate heat in the future. [ABSTRACT FROM AUTHOR]

Challenges to sustainable agriculture are increasing with forecasts for greater climate variability, including rising temperatures, extreme precipitation events, and prolonged droughts. One important factor that contributes to the increasing climate variability is greenhouse gas emissions, including from agro-ecosystems. The US Environment Protection Agency indicates soil management and enteric fermentation from livestock contribute ~ 80% of total greenhouse gas from agriculture sector. Management practices conducive to greenhouse gas emissions, and possible mitigation strategies for the agricultural systems of Southern Great Plains, an integral part of the US beef industry, have not been thoroughly defined. The objective of this paper is to review and synthesize the literature regarding management practices conducive to emissions [carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4)] from croplands and grazing lands of Southern Great Plains, and potential strategies that may aid in greenhouse gas mitigation in the region. The results from different published studies evaluating such strategies were analyzed to determine whether these practices have potential in mitigating greenhouse gas emissions from agronomic and grazing lands. Based on the analysis, it can be recommended that increasing the amount of cropland managed by conservation tillage, fertilizer management, crop rotation systems, grazing management, and fertilizer amendments can be potential management strategies for greenhouse gas mitigation. As agro-ecosystems are very complex and reducing emissions using strategies in one sector may stimulate higher emissions in other sectors, these strategies require testing at the systems-level before they can be implemented to advise applied policies for the Southern Great Plains region. [ABSTRACT FROM AUTHOR]

This paper describes the potential application of a new patented technology for the storage of carbon dioxide (CO2) in glass containers into the deep seabed (confined submarine carbon storage (CSCS)) to cement plants located in four different locations in the world. This technology is based on the bottling of liquid CO2 at high pressure inside capsules made of glass that are delivered to the bottom of the ocean via a proper pipeline. A Life Cycle Assessment that considers all the stages of the process and 13 impact categories, with a focus on climate change, shows an impact in the four case studies between 0.084 and 0.132 ton of CO2 equivalent (eq) per ton of CO2 stored. Since carbonation of cement materials over their life cycle is a significant and growing net sink of CO2, the capture and storage of CO2 emissions generated during the production of cement might lead to negative emissions. A cost analysis was also performed, including the capital costs and the operational costs, even considering the funding structure through financing and equity. The costs of the four case studies are from 16 to 29 $/tCO2. Although further work is needed to assess in detail some aspects of the design, the result of this stage of the research allows concluding that the application of the CSCS in cement plants is an interesting option for achieving negative emissions, even if limited due the slowness of CO2 uptake during the lifetime of cement materials. [ABSTRACT FROM AUTHOR]

Direct air capture (DAC) is a developing technology for removing carbon dioxide (CO2) from the atmosphere or from low-CO2-containing sources. In principle, it could be used to remove sufficient CO2 from the atmosphere to compensate for hard-to-decarbonize sectors, such as aviation, or even for polishing gas streams containing relatively low CO2 concentrations. In this paper, the performance of lime-based sorbents for CO2 capture from air in a fixed bed was investigated. The effects of sorbent type, particle diameter, air flow rate, and relative humidity on the breakthrough time, breakthrough shape, and global reaction rate over a series of capture and regeneration cycles were examined. The greatest reaction rates and conversions were obtained when the sorbents were pre-hydrated and inlet air was humidified to 55% relative humidity. Humidifying the air alone leads to axial carbonation gradients since there is competition between CO2 and water with the available CaO. Negligible conversion, over the duration of the experiment, is obtained in a dry system without pre-hydration and humid air. A shrinking-core gas–solid reaction model was fitted to the breakthrough curves in order to estimate the surface reaction and effective diffusion constants. Although the surface reaction constants of the two sorbents were similar, the pelletized limestone had a greater effective diffusivity due to its greater porosity. At mild calcination conditions with air at 850 °C, the pelletized particles maintained their activity over nine carbonation–calcination cycles with a conversion drop of only 9% points. However, calcination under oxy-fuel conditions (CO2 at 920 °C) reduced the pellet carbonation conversion from 81 to 59% and pore surface area from 12.01 to 3.20 m2/g after only 4 cycles. This research clearly shows that DAC using lime-based sorbents is technically feasible, and that regeneration schemes compatible with technologies like calcium looping (CaL) are applicable for the air capture option. Finally, this study demonstrates that DAC using lime-based materials can be in the future a strategy to address emissions from transportation and distributed CO2 sources and to mitigate climate change. [ABSTRACT FROM AUTHOR]

Emission inventories (EIs) are the fundamental tool to monitor compliance with greenhouse gas (GHG) emissions and emission reduction commitments. Inventory accounting guidelines provide the best practices to help EI compilers across different countries and regions make comparable, national emission estimates regardless of differences in data availability. However, there are a variety of sources of error and uncertainty that originate beyond what the inventory guidelines can define. Spatially explicit EIs, which are a key product for atmospheric modeling applications, are often developed for research purposes and there are no specific guidelines to achieve spatial emission estimates. The errors and uncertainties associated with the spatial estimates are unique to the approaches employed and are often difficult to assess. This study compares the global, high-resolution (1 km), fossil fuel, carbon dioxide (CO2), gridded EI Open-source Data Inventory for Anthropogenic CO2 (ODIAC) with the multi-resolution, spatially explicit bottom-up EI geoinformation technologies, spatio-temporal approaches, and full carbon account for improving the accuracy of GHG inventories (GESAPU) over the domain of Poland. By taking full advantage of the data granularity that bottom-up EI offers, this study characterized the potential biases in spatial disaggregation by emission sector (point and non-point emissions) across different scales (national, subnational/regional, and urban policy-relevant scales) and identified the root causes. While two EIs are in agreement in total and sectoral emissions (2.2% for the total emissions), the emission spatial patterns showed large differences (10~100% relative differences at 1 km) especially at the urban-rural transitioning areas (90–100%). We however found that the agreement of emissions over urban areas is surprisingly good compared with the estimates previously reported for US cities. This paper also discusses the use of spatially explicit EIs for climate mitigation applications beyond the common use in atmospheric modeling. We conclude with a discussion of current and future challenges of EIs in support of successful implementation of GHG emission monitoring and mitigation activity under the Paris Climate Agreement from the United Nations Framework Convention on Climate Change (UNFCCC) 21st Conference of the Parties (COP21). We highlight the importance of capacity building for EI development and coordinated research efforts of EI, atmospheric observations, and modeling to overcome the challenges. [ABSTRACT FROM AUTHOR]

Simplified modalities and procedures (M&P) are expected to increase the viability of small-scale project activities under the Clean Development Mechanism (CDM). A small-scale afforestation or reforestation (AR) project is defined as a project removing less than 8 kilotons of carbon dioxide equivalent (CO2e) per year. Depending on the project type and the method for measuring scale, 8 kilotons of CO2e per year correspond to highly diverse areas, possibly ranging from 200 to 6000 ha. Using a model to calculate the minimum project scale above which the CDM is a positive financial incentive for eligible AR project activities, the paper analyzes whether a reduction of transaction costs under simplified M&P will be a sufficient incentive to motivate small-scale participation in the CDM. Model results show that, even under optimistic assumptions on carbon market conditions and transaction costs, small-scale project activities will not benefit from simplified M&P. Results also show that project activities removing more than 8 kilotons of CO2e per year and registered as small-scale would be the ones that could benefit the most from simplified M&P. It is concluded that the participation of small-scale project activities to the CDM requires more than simplified M&P, the price of expiring Certified Emission Reductions being one of the most critical parameters. [ABSTRACT FROM AUTHOR]

There has been growing concern over the build-up of greenhouse gase (GHGs) in the atmosphere, particularly carbon dioxide (CO2), as a cause of global warming. The IPCC Third Assessment Report (2001) suggests two ways in which the choice of materials could be relevant. First, some materials, particularly wood, have the advantage that they continue to hold carbon (C)in their cells even after being converted to products. The implications of this feature are well researched. Second, an area that is not well researched relates to the different energy requirements for producing similar products made with different materials. Using the findings of recent research, this paper compares the energy requirements and C emissions of manufacturing a product using wood with that of other materials. The case study of utility poles demonstrates the positive C and global warming consequences of the lower energy requirements of wood in the U.S., compared to other materials such as steel or concrete. It demonstrates that GHG emissions associated with utility poles are a small but significant percent of total US annual emissions. Wood utility poles are associated with GHG emission reductions of 163 Terragrams (Tg) of CO2 when compared with steel poles. This is about 2.8 percent of US annual GHG emissions, which are estimated at about 5.28 Petragrams (Pg) of CO2 annually. Thus, the use of wooden utility poles rather than steel results in a small but significant reduction in total US emissions. [ABSTRACT FROM AUTHOR]

Economic incentives for sequestering atmospheric carbon dioxide (CO_2) in forests may be an effective way to meet greenhouse gas (GHG) reduction commitments under the Kyoto Protocol (KP). But concerns have been raised that the KP may create unintended incentives to excessively harvest existing forests if regenerated forests qualify for carbon (C) credits under the reforestation provision of Article 3.3. This paper combines an analytical model of the optimal forest rotation with both timber and C as priced outputs with data on timber and C growth and yield to different forest settings in the U.S. C prices of $50 per megagram (Mg) ? the highest price evaluated ? can considerably lengthen forest rotations (40 years or more), raise forest land values (as much as $1,900 per hectare), and sequester more C in the long run (up to 60 percent per acre), relative to the base case of no C compensation. However, if C payments are made for the regenerated stand only, in some situations, it is optimal to immediately harvest an otherwise premature stand at C prices as low as $20/Mg. The strength of perverse incentives to accelerate harvesting of existing forest varies by forest type, region, C price level, and institutional factors relevant to the compensation system. If C compensation were extended to existing stands, as may be possible under Article 3.4 of the KP, the perverse incentives for prematurely harvesting existing stands would not exist. [ABSTRACT FROM AUTHOR]

The quantification of fossil-fuel-related emissions of carbon dioxide to the atmosphere is necessary in order to accurately represent carbon cycle fluxes and to understand and project the details of the global carbon cycle. In addition, the monitoring, reporting, and verification (MRV) of carbon dioxide emissions is necessary for the success of international agreements to reduce emissions. However, existing fossil-fuel carbon dioxide (FFCO) emissions inventories vary in terms of the data and methods used to estimate and distribute FFCO. This paper compares how the approaches used to create spatially explicit FFCO emissions inventories affect the spatial distribution of emissions estimates and the magnitude of emissions estimates in specific locales. Five spatially explicit FFCO emission inventories were compared: Carbon Dioxide Information and Analysis Center (CDIAC), Emission Database for Global Atmospheric Research (EDGAR), Fossil Fuel Data Assimilation System (FFDAS), Open-source Data Inventory for Anthropogenic CO (ODIAC), and Vulcan. The effects of using specific data and approaches in the creation of spatially explicit FFCO emissions inventories, and the effect of resolution on data representation are analyzed using graphical, numerical, and cartographic approaches. We examined the effect of using top-down versus bottom-up approaches, nightlights versus population proxies, and the inclusion of large point sources. The results indicate that the approach used to distribute emissions in space creates distinct patterns in the distribution of emissions estimates and hence in the estimates of emissions in specific locations. The different datasets serve different purposes but collectively show the key role of large point sources and urban centers and the strong relationship between scale and uncertainty. [ABSTRACT FROM AUTHOR]

The article focuses on mitigation of greenhouse gas (GHG) emissions in agricultural sector in Spain. Topics discussed include emission of nitrous oxide (N2O) from agricultural soils due to application of manures and fertilizers, removal of carbon dioxide (CO2) by carbon which gets accumulated in plant biomass and diversity in climate of Spain affect production systems of livestock with their environment.

Energy and energy services are the backbone of growth and development in India and is increasingly dependent upon the use of fossil based fuels that lead to greenhouse gases (GHG) emissions and related concerns. Algal biofuels are being evolved as carbon (C) -neutral alternative biofuels. Algae are photosynthetic microorganisms that convert sunlight, water and carbon dioxide (CO) to various sugars and lipids Tri-Acyl-Glycols (TAG) and show promise as an alternative, renewable and green fuel source for India. Compared to land based oilseed crops algae have potentially higher yields (5-12 g/m/d) and can use locations and water resources not suited for agriculture. Within India, there is little additional land area for algal cultivation and therefore needs to be carried out in places that are already used for agriculture, e.g. flooded paddy lands (20 Mha) with village level technologies and on saline wastelands (3 Mha). Cultivating algae under such conditions requires novel multi-tier, multi-cyclic approaches of sharing land area without causing threats to food and water security as well as demand for additional fertilizer resources by adopting multi-tier cropping (algae-paddy) in decentralized open pond systems. A large part of the algal biofuel production is possible in flooded paddy crop land before the crop reaches dense canopies, in wastewaters (40 billion litres per day), in salt affected lands and in nutrient/diversity impoverished shallow coastline fishery. Mitigation will be achieved through avoidance of GHG, C-capture options and substitution of fossil fuels. Estimates made in this paper suggest that nearly half of the current transportation petro-fuels could be produced at such locations without disruption of food security, water security or overall sustainability. This shift can also provide significant mitigation avenues. The major adaptation needs are related to socio-technical acceptance for reuse of various wastelands, wastewaters and waste-derived energy and by-products through policy and attitude change efforts. [ABSTRACT FROM AUTHOR]

To prepare agricultural systems for climate change, scientists need to be able to effectively engage with land managers and policy makers to explore potential solutions. An ongoing challenge in engagement is to distil the complexity of climate-change-management-change interactions in agro-ecological systems to identify responses that are most important for adaptation planning. This paper presents an approach for selecting climate change scenarios to provide a focal point for engaging with stakeholders to evaluate adaptation options and communicate assessment outcomes. We illustrate how scenarios selected with the approach can be used by evaluating climate change impacts and an adaptation option for livestock industries in the north-east Australian rangelands. Climate change impacts on forage production, animal liveweight gain and soil loss are found to track projected climate changes in four pasture communities; increasing by up to 50% and declining by up to 110% in response to doubled atmospheric carbon-dioxide (CO), 4°C warming, and +20% to −40% changes in mean annual rainfall. The effectiveness of reducing grazing pressure as an adaptation option shows a similar response; resulting in higher forage production (up to 40%), animal liveweight gains (up to 59%) and gross margins (up to 40%), and reduced soil erosion (down by 91%) per hectare relative to the baseline management. The results show that a few key scenarios may be selected to represent the range of global climate model (GCM) projections for use in assessing and communicating impacts and adaptation; simplifying the assessments and allowing limits to the effectiveness of adaptation options to be explored. The approach provides a framework for capturing and communicating trends in climate change impacts and the utility of options, which are required for successful engagement of stakeholders in finding viable adaption responses. [ABSTRACT FROM AUTHOR]

Carbon dioxide capture and storage (CCS) has recently been receiving increasing recognition in policy debates. Various aspects of possible regulatory frameworks for its implementation are beginning to be discussed in Europe. One of the issues associated with the wide use of CCS is that it requires the establishment of a carbon dioxide (CO) transport network, which could result in the spatial restructuring of power generation and transmission systems. This poses a significant coordination problem necessitating public planning and regulation. This paper provides a survey over multiple research strands on CCS, particularly energy system modeling and spatial optimization, pertaining to the efficient installment of CCS-related infrastructure throughout Europe. It integrates existing findings and highlights the factors that determine policy coordination needs for a potential wide implementation of CCS in the next decades. [ABSTRACT FROM AUTHOR]

Stabilization of CO atmospheric concentrations requires practical strategies to address the challenges posed by the continued use of coal for baseload-electricity production. Over the next two decades, CO capture and sequestration (CCS) demonstration projects would need to increase several orders of magnitude across the globe in both size and scale. This task has several potential barriers which will have to be accounted for. These barriers include those that have been known for a number of years including safety of subsurface sequestration, pore-space competition with emerging activities like shale gas production, legal and regulatory frameworks, and public acceptance and technical communication. In addition water management is a new challenge that should be actively and carefully considered across all CCS operations. A review of the new insights gained on these previously and newly identified challenges, since the IPCC special report on CCS, is presented in this paper. While somewhat daunting in scope, some of these challenges can be addressed more easily by recognizing the potential advantageous synergies that can be exploited when these challenges are dealt with in combination. For example, active management of water resources, including brine in deep subsurface formations, can provide the additional cooling-water required by the CO capture retrofitting process while simultaneously reducing sequestration leakage risk and furthering efforts toward public acceptance. This comprehensive assessment indicates that water, sequestration, legal, and public acceptance challenges ought to be researched individually, but must also be examined collectively to exploit the promising synergies identified herein. Exploitation of these synergies provides the best possibilities for successful large-scale implementation of CCS. [ABSTRACT FROM AUTHOR]

The paper aims to assess the potential of decentralized bioenergy technologies in meeting rural energy needs and reducing carbon dioxide (CO2) emissions. Decentralized energy planning is carried out for the year 2005 and 2020. Decentralized energy planning model using goal programming technique is applied for different decentralized scales (village to a district) for obtaining the optimal mix of energy resources and technologies. Results show that it is possible to meet the energy requirements of all the services that are necessary to promote development and improve the quality of life in rural areas from village to district scale, by utilizing the locally available energy resources such as cattle dung, leaf litter and woody biomass feedstock from bioenergy plantation on wastelands. The decentralized energy planning model shows that biomass feedstock required at village to district level can even be obtained from biomass conserved by shifting to biogas for cooking. Under sustainable development scenario, the decentralized energy planning model shows that there is negligible emission of CO2, oxide of Sulphur (SOx) and oxide of nitrogen (NOx), even while meeting all the energy needs. [ABSTRACT FROM AUTHOR]

This paper empirically shows how the uncertainty associated to the absence of a mitigation regime which follows the United Nations Framework Convention on Climate Change Kyoto Protocol (UN FCCC Kyoto Protocol) is affecting investments in abatement activities in the EU electricity sector and, thus, future emissions levels. Based on a survey of EU electric utilities, it identifies the most likely post-Kyoto scenarios considered by them and how they are coping with such uncertainty in their investment decisions. It is found that firms react differently to such uncertainty and adopt different strategies to cope with it, diversifying their emissions control activities. Although most companies foresee post-Kyoto compliance regimes with emissions trading systems, they differ in their perceptions of the form that a post-Kyoto regime could take and are, thus, positioning differently to face such regime. The particular features of each company and the country where they operate affect their perception of the uncertainties, their position regarding a possible post-Kyoto regime and their inclination to carry out mitigation activities. Complying with Kyoto (and, eventually, post-Kyoto) targets significantly influences the investment decisions of European electricity companies. Uncertainty about a post-Kyoto regime may already be affecting investments in mitigation activities in the electricity sector. Therefore, significant progress has to be made in the definition of a post-Kyoto regime. It is urgent to define and agree internationally the emissions reduction objectives and the mitigation instruments that will be accepted for compliance, ensuring continuity of the international emissions trading system foreseen in the Kyoto Protocol. [ABSTRACT FROM AUTHOR]

Climate change is creating substantial and growing impacts on the Northeastern United States. As the world's seventh largest contributor of heat trapping carbon dioxide, the region will play a critical role inmoving towards stabilizing global concentrations at a level that avoids serious adverse consequences. The Northeast region is well positioned to be a leader in technology and policy innovation for reducing emissions, and can drive national and international programs that are essential to providing a safer future climate. This paper summarizes technological mitigation options and measures as well as opportunities for public and private actions to reduce emissions. The authors propose a '3% solution' of annual emission reductions to put the Northeastern United States on an emissions reductions path that is consistent with the level of reductions necessary to avoid dangerous climate change. The 3% solution requires a combination of policies that will reduce the energy imbedded in the region's infrastructure and technologies, and individual action to choose the lowest emitting of available technologies and practices. [ABSTRACT FROM AUTHOR]

Fire is the major stand-renewing disturbance in the circumboreal forest. Weather and climate are the most important factors influencing fire activity and these factors are changing due to human-caused climate change. This paper discusses and synthesises the current state of fire and climate change research and the potential direction for future studies on fire and climate change. In the future, under a warmer climate, we expect more severe fire weather, more area burned, more ignitions and a longer fire season. Although there will be large spatial and temporal variation in the fire activity response to climate change. This field of research allows us to better understand the interactions and feedbacks between fire, climate, vegetation and humans and to identify vulnerable regions. Lastly, projections of fire activity for this century can be used to explore options for mitigation and adaptation. [ABSTRACT FROM AUTHOR]

Fuelwood plays an important role in the rural economy of the developing countries of Asia and Africa. Optimizing energy fixation in forest trees through high density energy plantations (HDEP), gasification of wood, and conversion of forest tree biomass, are some of the potential areas whereby additional research and development input for efficient management of atmospheric carbon in our energy system can be incorporated. For example, the photosynthetic efficiency of forest trees is rarely above 0.5%, which on the basis of theoretical considerations can be increased by up to 6.6%. Thus there is an ample scope to improve the efficiency up to 1%, which amounts to doubling of the productivity of the forests. Recent policy changes and experiences with wood-based bio-energy programmes in several countries indicate that woodfuels may become increasingly attractive as industrial energy sources. Use of biodiesel and the formulation of a project for undertaking 13.4 million ha of Jatropha plantations in India highlight the seriousness with which the Government of India is promoting carbon neutral energy plantations. The cost of establishment of plantations primarily for fuel production and its conversion to energy are major deterrents in this pursuit. Some of the issues in developing countries, like low productivity on marginal lands, degraded forest lands, and unorganized units for biomass energy conversion, result in cost escalation as compared to other energy sources. This paper revisits the scope for raising energy plantations, a comparison of the direct and indirect mitigation potential uses of plantations as an adaptation strategy through reforestation and afforestation projects for climate change mitigation and socio-economic issues to make this venture feasible in developing countries. [ABSTRACT FROM AUTHOR]

The intensive use of renewable energy is one of the options to stabilize CO2 atmospheric concentration at levels of 350 to 550 ppm. A recent evaluation of the global potential of primary renewable energy carried out by Intergovernmental Panel on Climate Change (IPCC) sets a value of at least 2800 EJ/yr, which is more than the most energy-intensive SRES scenario forecast for the world energy requirement up to the year 2100. Nevertheless, what is really important to quantify is the amount of final energy since the use of renewable sources may involve conversion efficiencies, from primary to final energy, different from the ones of conventional energy sources. In reality, IPCC does not provide a complete account of the final energy from renewables, but the text claims that using several available options to mitigate climate change, and renewables is only one of them, it is possible to stabilize atmospheric carbon dioxide (CO2) concentration at a low level. In this paper, we evaluate in detail biomass primary and final energy using sugarcane crop as a proxy, since it is one of the highest energy density forms of biomass, and through afforestation/reforestation using a model presented in IPCC Second Assessment Report (SAR). The conclusion is that the primary-energy potential for biomass has been under-evaluated by many authors and by IPCC, and this under-evaluation is even larger for final energy since sugarcane allows co-production of electricity and liquid fuel. Regarding forests we reproduce IPCC results for primary energy and calculate final energy. Sugarcane is a tropical crop and cannot be grown in all the land area forecasted for biomass energy plantation in the IPCC/TAR evaluation (i.e. 1280 Mha). Nevertheless, there are large expanses of unexploited land, mainly in Latin America and Africa that are subject to warm weather and convenient rainfall. With the use of 143 Mha of these lands it is possible to produce 164 EJ/yr (1147 GJ/ha yr or 3.6 W/m² on average) of primary energy and 90 EJ/yr of final energy in the form of liquid fuel (alcohol) and electricity, using agricultural productivities near the best ones already achievable and biomass gasification technology. More remarkable is that these results can be obtained with the operation of 4,000 production units with unitary capacity similar to the largest currently in operation. These units should be spread over the tropical land area yielding a plantation density similar to the one presently observed in the state of São Paulo, Brazil, where alcohol and electricity have been commercialized in a cost-effective way for several years. Such an amount of final energy would be sufficiently large to fulfill all the expected global increase in oil demand, as well as in electricity consumption by 2030, assuming the energy demand of such sources continues to grow at the same pace observed over the last two decades. When sugarcane crops are combined with afforestation/reforestation it is possible to show that carbon emissions decline for some IPCC SRES scenarios by 2030, 2040 and 2050. Such energy alternatives significantly reduce CO2 emissions by displacing fossil fuels and promote sustainable development through the creation of millions of direct and indirect jobs. Also, it opens an opportunity for negative CO2 emissions when coupled with carbon dioxide capture and storage. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) capture and storage is increasingly being considered as an important climate change mitigation option. This paper explores provisions for including geological CO2 storage in climate policy. The storage capacity of Norway's Continental Shelf is alone sufficient to store a large share of European CO2 emissions for many decades. If CO2 is injected into oil reservoirs there is an additional benefit in terms of enhanced oil recovery. However, there are significant technical and economic challenges, including the large investment in infrastructure required, with related economies of scale properties. Thus CO2 capture, transportation and storage projects are likely to be more economically attractive if developed on a large scale, which could mean involving two or more nations. An additional challenge is the risk of future leakages from storage sites, where the government must take on a major responsibility. In institutional and policy terms, important challenges are the unsettled status of geological CO2 storage as a policy measure in the Kyoto Protocol, lack of relevant reporting and verification procedures, and lack of decisions on how the option should be linked to the flexibility mechanisms under the Kyoto Protocol. In terms of competitiveness with expected prices for CO2 permits under Kyoto Protocol trading, the relatively high costs per tonne of CO2 stored means that geological CO2 storage is primarily of interest where enhanced oil recovery is possible. These shortcomings and uncertainties mean that companies and governments today only have weak incentives to venture into geological CO2 storage. [ABSTRACT FROM AUTHOR]

Emissions trading is an attractive candidate for implementing greenhouse gas mitigation, because it can promote both efficiency and equity. This paper analyzes the interregional impacts of alternative allocations of carbon dioxide emission permits within the U.S. The analysis is performed with the aid of a nonlinear programming model for ten EPA Regions and for six alternative permit distribution formulas. The reason that various alternatives need to be considered is that there is no universal consensus on the best definition of equity. Advance knowledge of absolute and relative regional economic impacts provides policy-makers with a stronger basis for making the choice. The analysis yields several useful results. First, the simulations indicate that no matter how permits are allocated, this policy instrument can substantially reduce the cost of GHG mitigation for the U.S. in comparison to a system of fixed quotas for each of its regions. Interestingly, the welfare impacts of several of the allocation formulas differ only slightly despite the large differences in their philosophical underpinnings. Also, the results for some equity criteria differ greatly from their application in the international domain. For example, the Egalitarian (per capita) criterion results in the relatively greatest cost burden being incurred by one of the regions of the U.S. with the lowest per capita income. [ABSTRACT FROM AUTHOR]

Carbon dioxide capture and permanent storage (CCS) is one of the most frequently discussed technologies with the potential to mitigate climate change. The natural target for CCS has been the carbon dioxide (CO2) emissions from fossil energy sources. However, CCS has also been suggested in combination with biomass during recent years. Given that the impact on the earth's radiative balance is the same whether CO2 emissions of a fossil or a biomass origin are captured and stored away from the atmosphere, we argue that an equal reward should be given for the CCS, independent of the origin of the CO2. The guidelines that provide assistance for the national greenhouse gas (GHG) accounting under the Kyoto Protocol have not considered CCS from biomass (biotic CCS) and it appears that it is not possible to receive emission credits for biotic CCS under the first commitment period of the Kyoto Protocol, i.e., 2008–2012. We argue that it would be unwise to exclude this GHG mitigation alternative from the competition with other GHG mitigation options. We also propose a feasible approach as to how emission credits for biotic CCS could be included within a future accounting framework. [ABSTRACT FROM AUTHOR]

Land-use emissions of greenhouse gases make up over one-third of current total anthropogenic emissions of greenhouse gases and about three-quarters of the total anthropogenic emissions of CH4 and N2O. Considering their contribution to global emissions, it is important to understand their future trends in order to anticipate and mitigate climate change. This paper reviews published scenarios of major categories of these emissions with the aim to provide background information for the development of new scenarios. These categories include CO2 from deforestation, CH4 from rice cultivation, CH4 from enteric fermentation of cattle, and N2O from fertilizer application. Base year estimates of all these categories varied greatly from reference to reference, and hence emissions of all scenarios were normalized relative to their 1990 value before being compared to one another. The range of published scenarios of CO2 emissions from deforestation is widest around the middle of the 21st century and then all scenarios converge to low values towards 2100. By contrast, the different scenarios of CH4 and N2O diverge with time, showing their widest range in 2100. Global emissions of CH4 from rice cultivation vary by a factor of three in 2100 and N2O from fertilized soils by a factor of 2.3. Emissions of CH4 from enteric fermentation of animals have the smallest range (factor of 2.0). The typical long-range trends of land-use emission scenarios vary greatly from region to region - they stabilize in industrialized regions after a few decades, but tend to stabilize later in developing regions or continue to grow throughout the 21st century. To improve the realism of the estimates of future trends of land-use emissions, it is especially important to improve the estimation of the future extent of agricultural land and the rate of deforestation, while taking into account significant driving forces such as the demand for agricultural commodities and crop yields. [ABSTRACT FROM AUTHOR]

China is among the largest emitters of carbon dioxide (CO2), worldwide Thus, its emissions mitigation is of global concern. The power generation sector is responsible for nearly half of China's total CO2 emissions and plays a key role in emissions mitigation. This study is an integrated evaluation of abatement technologies, including both low-carbon power generation technologies and retrofitting options for coal power plants. We draw marginal abatement cost curves for these technologies using the conservation supply curve method. Using scenario analysis for the years 2015 to 2030, we discuss the potential performance of abatement technologies. Marginal costs for the analyzed abatement technologies range from RMB − 357.41/ton CO2 to RMB 927.95/ton CO2. Furthermore, their cumulative mitigation potential relative to the baseline scenario could reach 35 billion tons of CO2 in 2015–2030, with low-carbon power generation technologies and coal power abatement technologies contributing 55% and 45% of the total mitigation, respectively. Our case study of China demonstrates the power generation sector's great potential to mitigate global emissions, and we suggest nuclear power, hydropower, and the comprehensive retrofitting of coal power as key technology options for the low-carbon transition of the energy system and long-term emissions mitigation strategies. [ABSTRACT FROM AUTHOR]

Future levels of climate change depend not only on carbon emissions but also on carbon uptake by the land and the ocean. Here we are using the Earth system model (ESM1) version of the Australian Community Climate and Earth System Simulator (ACCESS) to explore the potential and impact of removing carbon dioxide (CO2) from the atmosphere through the climate and carbon cycle reversibility experiment. This experiment builds on the standard Coupled Model Intercomparison Project (CMIP) experiment, increasing CO2 at 1% per year until 4xCO2 is reached. The atmospheric CO2 levels are then decreased at the same rate which brings the CO2 back to pre-industrial levels. We then continue to run the model with constant CO2 for another 350 years. Our analysis focuses on the response of the land carbon cycle. We find that carbon stores are largely reversible at the global scale over the timescale of changing CO2. However, carbon stores continue to decrease after CO2 returns to its initial value, and the land loses another 40 Pg of carbon (PgC) with the largest change in the tropics. It takes about 300 years beyond the period of changing CO2 for the carbon stores to recover. Interestingly, we saw strong regional variations in the strength of the land response to changing CO2. Australia showed the largest increase/decrease in biomass carbon (about 40%) and the largest variability in productivity, which was strongly correlated with rainfall. This highlights the importance of assessing the regional response to understanding the processes underlying the response and the sensitivity of these processes within each model. This understanding will benefit future multi-model analyses of this reversibility experiment. It also illustrates more generally the potential to use Earth system model experiments as part of the evaluation of proposed applications of carbon dioxide removal (CDR) technologies. As such, we recommend that these types of modelling experiments be included when mitigation policies are developed. [ABSTRACT FROM AUTHOR]

Carbon capture and storage (CCS) is an economically attractive strategy for avoiding carbon dioxide (CO2) emissions from, e.g., power plants to the atmosphere. The combination of CCS and biomass combustion would result in a reduction of atmospheric CO2, or net negative emissions, as plant growth is a form of sequestration of atmospheric carbon. Carbon capture can be achieved in a variety of ways, one of which is chemical looping. Chemical-looping combustion (CLC) and chemical looping gasification (CLG) are two promising technologies for conversion of biomass to heat and power or syngas/methane with carbon capture. There have been significant advances made with respect to CLC in the last two decades for all types of fuel, with much less research on the gasification technology. CLG offers some interesting opportunities for production of biofuels together with carbon capture and may have several advantages with respect to the bench mark indirect gasification process or dual-bed fluidized bed (DFBG) in this respect. In CLG, an oxygen carrier is used as a bed material instead of sand, which is common in indirect gasification, and this could have several advantages: (i) all generated CO2 is present together with the syngas or methane in the fuel reactor outlet stream, thus in a concentrated stream, viable for separation and capture; (ii) the air reactor (or combustion chamber) should largely be free from trace impurities, thus preventing corrosion and fouling in this reactor; and (iii) the highly oxidizing conditions in the fuel reactor together with solid oxide surfaces should be advantageous with respect to limiting formation of tar species. In this study, two manganese ores and an iron-based waste material, LD slag, were investigated with respect to performance in these chemical-looping technologies. The materials were also impregnated with alkali (K) in order to gauge possible catalytic effects and also to establish a better understanding of the general behavior of oxygen carriers with alkali, an important component in biomass and biomass waste streams and often a precursor for high-temperature corrosion. The viability of the oxygen carriers was investigated using a synthetic biogas in a batch fluidized bed reactor. The conversion of CO, H2, CH4, and C2H4 was investigated in the temperature interval 800–950 °C. The reactivity, or oxygen transfer rate, was highest for the manganese ores, followed by the LD slag. The conversion of C2H4 was generally high but could largely be attributed to thermal decomposition. The K-impregnated samples showed enhanced reactivity during combustion conditions, and the Mangagran-K sample was able to achieve full conversion of benzene. The interaction of the solid material with alkali showed widely different behavior. The two manganese ores retained almost all alkali after redox testing, albeit exhibiting different migration patterns inside the particles. LD slag lost most alkali to the gas phase during testing, although some remained, possibly explaining a small difference in reactivity. In summary, the CLC and CLG processes could clearly be interesting for production of heat, power, or biofuel with negative CO2 emissions. Manganese ores are most promising from this study, as they could absorb alkali, giving a better conversion and perhaps also inhibiting or limiting corrosion mechanisms in a combustor or gasifier. [ABSTRACT FROM AUTHOR]

Negative emission technologies (NETs) are a set of technologies that could retrieve greenhouse gases from the atmosphere. NETs could dramatically contribute to maintaining the temperature increase to within the limit of 2 °C or even 1.5 °C. Bioenergy with carbon capture and storage (BECCS) is one of the most studied NETs. BECCS captures carbon dioxide (CO2) emissions coming from a bioenergy plant—e.g., electricity, biofuels, and hydrogen—and stores those emissions in a geologic reservoir, typically a saline aquifer. The purpose of this article is to investigate whether a research community exists on BECCS, and whether it is aligned with research priorities. To do so, a bibliometric analysis is conducted based on author collaborations on BECCS in academic journals between 2001 and 2017. The co-authorship network shows that BECCS research is largely based on the integrated assessment model (IAM) research community. These models analyze how power and transportation systems evolve under a climate constraint in the long run, e.g., until 2100. Such a focus has advantages and drawbacks. On the one hand, it helps to build a common vision of the technology and possible roadmaps. On the other hand, I highlight that the implementation features of BECCS in the near future are insufficiently assessed, e.g., techno-economic analyses, business models, local-scale assessments, and comparison with other NETs. These issues are marginal in the network, whereas long-term analyses are at its core. Future research programmes should better include them to avoid a considerable disappointment about the real potential of BECCS. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) emissions from China are of global concern. As energy-, resource-intensive and greenhouse gas (GHG) pollution emissions, China's cement-related CO2 emissions and environmental effect attracted more and more attention reasonably. A multiple-year's cement CO2 emissions were estimated in China based on actual and projected cement output and CO2 emission factor (EF) from the perspective of technological improvement for the period 1949–2050. The more than 100 years' time scale was divided into three periods: 1949–1979, 1980–2015, and 2016–2050, which mainly based on China's socio-economy and technological improvement (i.e., transformed cement kilns and popularized waste heat recovery, WHR). The bottom-up model was used for calculating cement-related CO2 emissions after analyzing processes of cement production, and we found China's comprehensive cement CO2 EF (CCEF) was about 1694.31 kg CO2 per ton of cement in 1949, and declined to 737.01 kg CO2 per ton of cement in 2015. Furthermore, it is likely that China's cement output is about 1617.50 Mt in 2050. Meanwhile, China's CCEF is about 576.02 kg CO2 per ton of cement which based on likely realistic scenario (LRS), and CO2 emissions are about 931.71 Mt in 2050, which is about half lower than those in 2014. It is important for calculating China's cement emissions in the society and rank around the world. For China's cement CO2 emission reduction, the contribution of technological innovation or improvement (TII) was undeniable, but the degree of CO2 reduction was limited, especially when the technological diffusion rate was close to saturation. The Chinese government is ambitious in controlling cement-related CO2 emissions and should start with controlling cement capacity, utilization of alternative raw materials (ARMs) and alternative fuels (AFs), and establishing a sound carbon trading market. [ABSTRACT FROM AUTHOR]

Anthropogenic emissions of carbon dioxide (CO2) and methane (CH4) in the atmosphere constitute an important component of the related carbon budget. The main source of anthropogenic CO2 is burning of fossil fuels, especially in densely populated areas. Similar emissions of CH4 are associated with the agricultural sector, coal mining, and other human activities, such as waste management and storage and natural gas networks supplying methane to large urban, industrial centers. We discuss several methods aimed at characterizing and quantifying atmospheric loads and fluxes of CO2 and CH4 in Krakow, the second largest city in Poland. The methods are based on atmospheric observations of mixing ratios as well as isotopic composition of the investigated gases. Atmospheric mixing ratios of CO2 and CH4 were measured using gas chromatography (GC) and cavity ring-down spectroscopy (CRDS). The isotopic composition of CO2 and CH4 was analyzed using isotope ratio mass spectrometry (IRMS), accelerator mass spectrometry (AMS), and CRDS techniques. These data, combined with auxiliary information characterizing the intensity of vertical mixing in the lower atmosphere (height of the nocturnal boundary layer [NBL] and atmospheric 222Rn concentration), were further used to quantify emission rates of CO2 and CH4 in the urban atmosphere of Krakow. These methods provide an efficient way of quantifying surface emissions of major greenhouse gases originating from distributed sources, thus complementing the widely used bottom-up methodology based on emission statistics. [ABSTRACT FROM AUTHOR]

In recent years, nations, states and provinces have been proactively combating climate change, supported by the 21st Conference of the Parties of the United Nations Framework Convention on Climate Change (UNFCCC) outcomes. In the meantime, several studies have evaluated regional strategies for greenhouse gas (GHG) mitigation. Although these studies propose scenarios that meet the climate policy pledges, most of them are based on measures that have not been commercially demonstrated yet, such as carbon capture and storage (CCS). The aim of this work is to develop a low-carbon scenario for the energy sector in Sao Paulo, Brazil (whose emissions are significant at the regional and national level) until 2050 and to verify if a proven, technology-based approach meets the current policy goals. Although the analysis is based on a developing country, Sao Paulo state is the most developed region in Brazil. Consequently, the analysis presented in this work may be replicated in other regional settings, with distinct development stages, which demand increasing energy futures. In the business-as-usual (BAU) scenario, energy demand increases 2.6% per year until 2050, and emissions consequently increase 2.8% per year, reaching 235 million metric tons of carbon dioxide (tCO2). If four alternatives proposed in the low-carbon (LC) scenario were implemented, 28% of the BAU emissions would be avoided. However, even with this LC scenario, Sao Paulo would not meet the state pledge, remaining 44% above the policy emission cap. This result means that more audacious measures are needed to achieve an effective result. Such measures must push the current technical, scientific, and industrial knowledge and may require a biodiesel share over 20% in diesel blend, extensive increases in renewable energy supply, CCS, and bioenergy associated with CCS. Finally, we suggest some key points to apply this analysis in other regions, considering their own energy mix. [ABSTRACT FROM AUTHOR]

The greenhouse gas (GHG) emissions of the global ceramic production is estimated at more than 400 Mt CO2/year, which have increased steadily from economic growth. Among ceramic industries, ceramic tableware industry (CTI) is a highly energy-intensive and high GHG emissions industry. Thailand was the fourth highest ranking ceramic tableware exporting country in the world. However, information on GHG emission from this industry was limited. This research aimed to investigate the carbon dioxide(CO2) intensity of CTI in Thailand and the annual projections of GHG emission during 2017-2050 with different GDP growths. Then, the energy saving potentials and GHG mitigation measures with their GHG abatement cost for small and large-scale CTI were proposed. The results indicated that the average CO2 intensity of Thailand CTI was 1.75 kg CO2e/kg of product. The projections for GHG emissions of ceramic tableware production with gross domestic production (GDP) growth rates of 1.5, 3.5 (BAU), and 5.5%, reached their maximum emissions at 220,500 t CO2 in 2029, 2022, and 2020, respectively. Under a BAU scenario, ceramic tableware production in 2022 would emit GHG at a rate approximately 1.37 times greater compared to the emissions in 2016. The maximum GHG reduction (100% implementation) was 48,902 t CO2e, accounting for 22% of GHG emissions in 2030. The average mitigation cost was 6.64 USD/t CO2e reduction. This study provided a guideline for the assessment of CO2 intensity and the technical information for long-term GHG emission projection in CTI which could be applied in worldwide. [ABSTRACT FROM AUTHOR]

Much attention is being paid toward reducing the carbon dioxide (CO2) emissions associated with China's cement production. However, as part of China's international commitment to reduce carbon intensity, the inter-annual changes and driving forces behind CO2 emissions must be determined for the 2001-2015 period, along with the projection of the cement-related CO2 emissions until 2030. The objective of this article is to analyze the CO2 emission factors (EFs) and CO2 emissions from 2001 to 2015, project CO2 emission scenarios of China's cement industry until 2030, and propose a low-carbon roadmap for the global cement industry by 2050 based on a series of practical reduction measurements performed by China. The results of our study indicate that CO2 EFs in 2015 were 55.36% lower than those in 2001, but CO2 emissions were 72.90% higher than those in 2001. The main reason for the decreasing total active CO2 EFs are policies enacted by the Chinese government regarding the removal of excess capacity and elimination of backward capacity as well as the technological innovation and ongoing annual reductions in the clinker-to-cement ratio (C/CR). Meanwhile, the driving force behind the increased cement-related CO2 emissions was the substantial growth in cement output. Scenarios regarding CO2 emissions by 2030 show an uncertainty regarding CO2 emissions, ranging between 3.51 and 11.70%, and CO2 EFs are expected to be 59-69% lower than those in 2005. CO2 emissions from the global cement industry from 2020 to 2050 based on CO2 capture, utilization, and storage (CCUS); utilization of alternative raw materials (ARMs) and alternative fossil fuels (AFFs); and technological innovation account for 39.3, 29.3, 24.7, and 6.7% of the CO2 reduction capability, respectively. It is possible to reduce ~ 1524 Mt of CO2, and the global optimal emissions by 2050 are ~ 2082 Mt of CO2. [ABSTRACT FROM AUTHOR]

One of the most serious concerns facing developing countries is high concentrations of ambient particulate matter (PM2.5). Concurrently, climate change has also been a major challenge for countries around the world. Energy systems are dominant emission sources of both PM2.5 and carbon dioxide (CO2). This study investigates cost-efficient energy system transitions for individual or dual targets of climate change mitigation and PM2.5 concentration reduction by a global energy systems model. We set two levels of mitigation efforts for each of the CO2 and PM2.5 emissions, whose stringent one corresponds to the long-term target of the Paris agreement and current national air quality standards, respectively. For PM2.5 reduction, a combination of moderate improvement in energy efficiency and a transition from coal to gas and renewable energies and a significant deployment of end-of-pipe measures for scrubbing air pollutants is shown to be among the most cost-efficient strategy. For CO2 reduction, drastic improvement in energy efficiency and a rapid transition from coal to gas, renewable and nuclear energies is the most cost-efficient strategy, in contrast. There is a larger co-benefit on PM2.5 concentration reduction from CO2 reduction measures than the converse, and the co-benefit varies regionally. Developing countries such as India have a huge potential of co-benefits, and energy efficiency improvement and fuel switching are key measures to bring them. The simultaneous achievement costs of the dual targets are smaller than the sum of individual achievement costs, and the cost reduction varies significantly depending on the level of each mitigation target. [ABSTRACT FROM AUTHOR]

This paper reviews and analyzes more than 400 scenarios of global and regional greenhouse gas emissions and their main driving forces - population, economy, energy intensity, and carbon intensity - drawn from an extensive literature survey and summarized in a database. This new and growing database is available online, which makes summary statistics on these scenarios widely available. The scenarios in the database were collected from almost 200 different literature sources andother scenario evaluation activities. The ultimate objective of the database is to include all relevant global and regional emissions scenarios. This paper shows how the database can be utilized for the analysis of greenhouse gas emissions ranges across the scenarios in the literature and for the analysis of their main driving forces. The scenarios in the database display a large range of future greenhouse gasemissions. Part of the range can be attributed to the different methods and models used to formulate the scenarios, which include simple spreadsheet models, macroeconomic models and systems-engineering models. However, most of the range is due to differences in the input assumptions for the scenarios, in particular of the main scenario driving forces. Special emphasis is given to an analysis of medians and ranges of scenario distributions and the distributions of the main scenario driving forces in the database. The analysis shows that the rangefor projected population increase in the world, across the scenariosin the database, is the smallest of all main driving forces (about afactor of 3 in 2100). The range of economic growth, measured by the gross world product, and the range of primary energy consumption varyby a factor of 10 in 2100. Carbon intensity of energy, an indicator of the degree of technological change, varies by nearly two orders ofmagnitude in the year 2100. In addition, this paper presents the first attempt to analyze the relationships among the main scenario driving forc [ABSTRACT FROM AUTHOR]

The objectives of this research are to assess the greenhouse gas mitigation potential of carbon policies applied to the ruminant livestock sector [inclusive of the major ruminant species—cattle (Bos Taurus and Bos indicus), sheep (Ovis aries), and goats (Capra hircus)]—with particular emphasis on understanding the adjustment challenges posed by such policies. We show that market-based mitigation policies can greatly amplify the mitigation potential identified in marginal abatement cost studies by harnessing powerful market forces such as product substitution and trade. We estimate that a carbon tax of US$20 per metric ton of carbon dioxide (CO2) equivalent emissions could mitigate 626 metric megatons of CO2 equivalent ruminant emissions per year (MtCO2-eq year−1). This policy would also incentivize a restructuring of cattle production, increasing the share of cattle meat coming from the multiproduct dairy sector compared to more emission intensive, single purpose beef sector. The mitigation potential from this simple policy represents an upper bound because it causes ruminant-based food production to fall and is therefore likely to be politically unpopular. In the spirit of the Paris Agreement (UNFCCC 2015), which expresses the ambition of reducing agricultural emissions while protecting food production, we assess a carbon policy that applies both a carbon tax and a subsidy to producers to manage the tradeoff between food production and mitigation. The policy maintains ruminant production and consumption levels in all regions, but for a much lower global emission reduction of 185 MtCO2-eq year−1. This research provides policymakers with a quantitative basis for designing policies that attempt to trade off mitigation effectiveness with producer and consumer welfare. [ABSTRACT FROM AUTHOR]

Climate change and energy service demand exert influence on each other through temperature change and greenhouse gas emissions. We have consistently evaluated global residential thermal demand and energy consumption up to the year 2050 under different climate change scenarios. We first constructed energy service demand intensity (energy service demand per household) functions for each of three services (space heating, space cooling, and water heating). The space heating and cooling demand in 2050 in the world as a whole become 2.1-2.3 and 3.8-4.5 times higher than the figures for 2010, whose ranges are originated from different global warming scenarios. Cost-effective residential energy consumption to satisfy service demand until 2050 was analyzed keeping consistency among different socio-economic conditions, ambient temperature, and carbon dioxide (CO) emission pathways using a global energy assessment model. Building shell improvement and fuel fuel-type transition reduce global final energy consumption for residential thermal heating by 30% in 2050 for a 2 °C target scenario. This study demonstrates that climate change affects residential space heating and cooling demand by regions, and their desirable strategies for cost-effective energy consumption depend on the global perspectives on CO emission reduction. Building shell improvement and energy efficiency improvement and fuel fuel-type transition of end-use technologies are considered to be robust measures for residential thermal demand under uncertain future CO emission pathways. [ABSTRACT FROM AUTHOR]

Despite the declining trends in total energy consumption, greenhouse gas emissions, energy intensity, and emission intensity over the past two decades, Romania still emits more greenhouse gas per unit of output than many other members of the European Union. The country is looking for further greening of its energy supply system to achieve the clean energy and climate change mitigation goals included in the European Union's 2030 target and 2050 Roadmap. Using an energy supply optimization model, TIMES, this study develops energy supply mixes for Romania under a baseline scenario that satisfies the European Union's current energy and climate targets for 2020, a green scenario that satisfies the European Union's 2030 energy and climate targets, and a super green scenario that satisfies the European Union's prospective 2050 energy road map. The study finds that although Romania could achieve the green scenario at a moderate cost, it would be challenging and costly to achieve the super green scenario. [ABSTRACT FROM AUTHOR]

Little is known about the multiple impacts of sustainable land management practices on soil and water conservation, carbon sequestration, mitigation of global change and crop yield productivity in semiarid Mediterranean agroecosystems. We hypothesized that a shift from intensive tillage to more conservative tillage management practices (reduced tillage optionally combined with green manure) leads to an improvement in soil structure and quality and will reduce soil erosion and enhance carbon sequestration in semiarid Mediterranean rainfed agroecosystems. To test the hypothesis, we assessed the effects of different tillage treatments (conventional (CT), reduced (RT), reduced tillage combined with green manure (RTG), and no tillage (NT)) on soil structure and soil water content, runoff and erosion control, soil carbon dioxide (CO) emissions, crop yield and carbon sequestration in two semiarid agroecosystems with organic rainfed almond ( Prunus dulcis Mill) in the Murcia Region (southeast Spain). It was found that reduction and suppression of tillage under almonds led to an increase in soil water content in both agroecosystems. Crop yields ranged from 775 to 1,766 kg ha between tillage treatments, but we did not find a clear relation between soil water content and crop yield. RT and RTG treatments showed lower soil erosion rates and higher crop yields of almonds than under CT treatment. Overall, higher soil organic carbon contents and aggregate stability were observed under RTG treatment than under RT or CT treatment. It is concluded that conversion from CT to RTG is suitable to increase carbon inputs without enhancing soil CO emissions in semiarid Mediterranean agroecosystems. [ABSTRACT FROM AUTHOR]

Afforestation and reforestation (A/R) projects generate greenhouse gas (GHG) reduction credits by removing carbon dioxide from the atmosphere through biophysical processes and storing it in terrestrial carbon stocks. One feature of A/R activities is the possibility of non-permanence, in which stored carbon is lost though natural or anthropogenic disturbances. The risk of non-permanence is currently addressed in Clean Development Mechanism (CDM) A/R projects through temporary carbon credits. To evaluate other approaches to address reversals and their implications for policy and investment decisions, we assess the performance of multiple policy and accounting mechanisms using a forest ecosystem simulation model parameterized with observational data on natural disturbances (e.g., fire and wind). Our analysis finds that location, project scale, and system dynamics all affect the performance of different risk mechanisms. We also find that there is power in risk diversification. Risk management mechanisms likewise exhibit a range of features and tradeoffs among risk conservatism, economic returns, and other factors. Rather than relying on a single approach, a menu-based system could be developed to provide entities the flexibility to choose among approaches, but care must be taken to avoid issues of adverse selection. [ABSTRACT FROM AUTHOR]

Cultivated organic soils are a remarkable source of greenhouse gases (GHG) in many countries. Keeping the ground water table as high as possible could lower the mineralization rate of the peat and thus the emissions of carbon dioxide (CO) and nitrous oxide (NO) from these soils. We studied the effect of raised water table on the emissions of NO, CO and methane (CH) from undisturbed peat soil profiles of six different Finnish cultivated organic soils during a 5-week outdoor mesocosm experiment. The aim was to determine an optimum water table that would enable grass cultivation but lower the net gas balance of the soil. Raised water table decreased the GHG emissions from each peat type ranging from weakly decomposed Sphagnum peat to highly humified Carex peat. Based on the results, the optimum water table would be 30 cm below the soil surface. The average reduction of the total net emissions with a raise of water table from a typical drainage depth of 70 to 30 cm was 42 % in the outdoors mesocosm experiment and 23 % at a constant temperature (+6 °C). The emissions of both CO and NO declined and the net consumption of CH changed to net production as the water table rose. The results were confirmed by long-term measurements at one of the sampled sites. As a conclusion, we see that promoting drainage systems enabling raising of the ground water table and cultivation of crops capable of producing good yields also in wet conditions would be beneficial for the GHG mitigation in agriculture. [ABSTRACT FROM AUTHOR]

The article focuses on the carbon capture and storage (CCS) systems. It says that the CCS demonstration of the Intergovernmental Panel on Climate Change (IPCC) in 2005 has provided large commercial or demonstration CCS projects in planning or operation. It also mentions that the slow progress of CCS projects was due to the postponed negotiation on international climate policy. Moreover, carbon dioxide transport infrastructure is required for the realization of CCS.

In the coming century, modern bioenergy crops have the potential to play a crucial role in the global energy mix, especially under policies to reduce carbon dioxide emissions as proposed by many in the international community. Previous studies have not fully addressed many of the dynamic interactions and effects of a policy-induced expansion of bioenergy crop production, particularly on crop yields and human food demand. This study combines an updated agriculture and land use (AgLU) model with a well-developed energy-economic model to provide an analysis of the effects of bioenergy crops on energy, agricultural and land use systems. The results indicate that carbon dioxide mitigation policies can stimulate a large production of bioenergy crops, dependent on the level of the policy. This production of bioenergy crops can lead to several impacts on the agriculture and land use system: decreases in forestland and unmanaged land, decreases in the average yield of food crops, increases in the prices of food crops, and decreases in the level of human demand of calories. [ABSTRACT FROM AUTHOR]