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The surge of carbon dioxide emission plays a dominant role in global warming and climate change, posing an enormous threat to the development of human being and a profound impact on the global ecosystem. Thus, it is essential to analyze the carbon dioxide emission change trend through an accurate prediction to inform reasonable energy-saving emission reduction measures and effectively control the carbon dioxide emission from the source. This paper proposed a hybrid model by combining the random forest and extreme learning machine together for the carbon dioxide emission forecasting in this paper; the random forest is applied for influential factors analysis and the extreme learning machine for the prediction. To improve the performance of the prediction model, moth-flame optimization is adopted to optimize initial weight and bias in extreme learning machine. A case study whose data is derived from Hebei Province, China, during the period 1995-2015 is conducted to verify the effectiveness of the proposed model. Results show that the novel model outperforms the compared parallel models in carbon dioxide emission prediction and has the potential to improve the accuracy of CO2 emission forecasting. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N2O) is the third important long‐lived greenhouse gas next to carbon dioxide and methane and croplands are considered biogeochemical hotspots of soil N2O emissions. To reduce soil N2O and other greenhouse emissions, climate‐smart agricultural practices including biochar application have been applied. Many studies have been conducted with biochar application but results from these studies are not conclusive. To address this issue, meta‐analysis, a quantitative review that synthesizes results from multiple independent studies, has been widely used. The results from different meta‐analyses also differ but are seldomly evaluated. In this study, we evaluated meta‐analyses on the effects of biochar application on soil N2O emissions. A grand mean response ratio (RR) was further proposed to estimate an overall effect and the impacts of experiment setting, properties of biochar and soil, and agricultural practices. We found 18 meta‐analysis papers were published between 2014 and 2022. Sample size (publications or experiments) varied from less than 30 to more than 1000, with a mean sample size of 275. RR was calculated in all studies except one. While four meta‐analyses did not find a significant effect of biochar application on soil N2O emissions, all others reported reductions of soil N2O emissions, but the magnitude ranged from −10.5% to −54.8%. Synthesizing all results from these meta‐analyses, we found that biochar application overall significantly reduced the soil N2O emissions by 38.8%. The impacts increased with experimental duration till one and half years and reduced after that. Biochar application rate and C:N ratio had large influence on the effects of biochar application on soil N2O emissions. This study demonstrated that while meta‐analysis provides a more comprehensive and better estimation, the inconsistence among these studies may need to be further evaluated. A grand mean RR based on meta‐analyses could be more accurate and representative than single meta‐analysis. [ABSTRACT FROM AUTHOR]

The Thermal and Near-Infrared Sensor for Carbon Observation Fourier-Transform Spectrometer-2 (TANSO-FTS-2) onboard the Japanese Greenhouse Gases Observing SATellite-2 (GOSAT-2) observes a wide spectral region of the atmosphere, from the ShortWave-InfraRed (SWIR) to the longwave Thermal InfraRed radiation (TIR) with 0.2 cm -1 spectral sampling, and the corresponding spectral resolution (full width at half maximum, FWHM) of TIR region is less than 0.27 cm -1. TANSO-FTS-2 has operated nominally since February 2019, and the atmospheric radiance spectra it has acquired have been released to the public. This paper describes an updated model for spectral radiance calibration and its validation. The model applies to the version v210210 TIR products of TANSO-FTS-2 and integrates polarization sensitivity correction for the internal optics and the pointing mirror thermal emission. These correction parameters are characterized by an optimization that depends on the difference between the spectral radiance of TANSO-FTS-2 and coincident nadir observation data from the Infrared Atmospheric Sounding Interferometer (IASI) on METOP-B. To validate the updated spectral radiance product against other satellite products, temporally and spatially coincident observation points were considered for the simultaneous nadir overpass (SNO) from February 2019 to March 2021 from the Atmospheric Infrared Sounder (AIRS) on Aqua, IASI on METOP-B, and TANSO-FTS on GOSAT. The agreement of brightness temperatures between TANSO-FTS-2 and AIRS and IASI was better than 0.3 K (1 σ) from 180 to 330 K for the 680 cm -1 CO 2 spectral range. The brightness temperatures between TANSO-FTS-2 and TANSO-FTS of version v230231, which implemented a new polarization reflectivity of the pointing mirror and was released in June 2021, generally agree from 220 to 320 K. However, there is a discrepancy at lower brightness temperatures, pronounced for CO 2 spectral ranges at high latitudes. To characterize the spectral radiance bias for along-track and cross-track angles, a 2-orthogonal simultaneous off-nadir overpass (2O-SONO) is now done for TANSO-FTS-2 and IASI, TANSO-FTS-2 and AIRS, and TANSO-FTS-2 and TANSO-FTS. The 2O-SONO comparison results indicate that the TIR product for TANSO-FTS-2 has a bias that exceeds 0.5 K in the CO 2 spectral range for scenes with forward and backward viewing angles greater than 20 ∘. These multi-satellite sensor and multi-angle comparison results suggest that the calibration of spectral radiance for TANSO-FTS-2 TIR, version v210210, is superior to that of the previous version in its consistency of multi-satellite sensor data. In addition, the paper identifies the remaining challenging issues in current TIR products. [ABSTRACT FROM AUTHOR]

The article discusses a study regarding the preliminary validation of column-averaged volume mixing ratios of carbon dioxide and methane retrieved from Greenhouse gases Observing SATellite (GOSAT) Short-Wavelength InfraRed spectra (GOSAT SWIR XCO2 and XCH4). The study compares the spectra's data with high-resolution Fourier Transform Spectrometers (g-b FTSs). It reveals that latitudinal distributions of zonal means of the spectra show similar features to g-b FTS data.

Global warming potential (GWP) is an important impact category in life-cycle-assessment modelling of waste management systems. However, accounting of biogenic CO2 emissions and sequestered biogenic carbon in landfills and in soils, amended with compost, is carried out in different ways in reported studies. A simplified model of carbon flows is presented for the waste management system and the surrounding industries, represented by the pulp and paper manufacturing industry, the forestry industry and the energy industry. The model calculated the load of C to the atmosphere, under ideal conditions, for 14 different waste management scenarios under a range of system boundary conditions and a constant consumption of C-product (here assumed to be paper) and energy production within the combined system. Five sets of criteria for assigning GWP indices to waste management systems were applied to the same 14 scenarios and tested for their ability to rank the waste management alternatives reflecting the resulting CO2 load to the atmosphere. Two complete criteria sets were identified yielding fully consistent results; one set considers biogenic CO2 as neutral, the other one did not. The results showed that criteria for assigning global warming contributions are partly linked to the system boundary conditions. While the boundary to the paper industry and the energy industry usually is specified in LCA studies, the boundary to the forestry industry and the interaction between forestry and the energy industry should also be specified and accounted for. [ABSTRACT FROM AUTHOR]

Spatiotemporal variations of industrial carbon emissions (IE) must be scientifically understood, which will be helpful to formulate reasonable emission reduction strategies. Given that spatial distribution of IE is irrelevant to space agents commonly used (such as population and nighttime light), estimation and spatialization methods for total carbon dioxide (CO2) emissions are not entirely suitable for IE. Therefore, this paper used greenhouse gases observing satellite level 4A product to estimate IE at the city level and used industrial land density to obtain the distribution of IE within the administrative districts. Sectoral emission inventories of 182 cities and a mosaic Asian anthropogenic emission inventory named MIX were used to verify the results. Then, spatiotemporal variation characteristics of China's IE were analyzed from multiple levels. Results showed that (1) the mean relative error of estimation results was 56.11%, among which 62 cities had relative error of less than 30%. Gridded IE in this paper had high consistency with MIX. (2) Cities with high IE experienced rapid growth from 2009 to 2012, followed by slower growth from 2012 to 2017. (3) Centroid of significant cold and hot spots moved to the southeast and northwest, respectively. Most cities with high annual IE growth had relatively low emission efficiency, mainly located in Inner Mongolia and Xinjiang. Aggregation of medium and high IE grids may represent high emission efficiency. Significant differences still exist between cities in IE, and sustainable development strategies should be formulated according to local conditions. Regions with high annual growth or low emission efficiency are the key to achieving IE reduction targets in future. [ABSTRACT FROM AUTHOR]

Featured Application: The Intergovernmental Panel on Climate Change (IPCC)'s Sixth Assessment Report (AR6) recognizes the physico-chemical process known as carbonation. The present paper utilizes a way of calculating carbon dioxide uptake quickly and easily following the simplified methodology known as Tier 1 applied to the largest cement consumer in South America. The worldwide cement industry plays an important role in addressing the climate change challenge. Brazil's cement industry currently has 91 cement plants with an installed production capacity of 94 million tons per year and has started to calculate the net CO2 emissions to achieve a carbon-neutral cement sector by 2050. Accordingly, the carbon dioxide uptake due to mortar and concrete carbonation is subtracted from the carbon dioxide emitted by the chemical reaction for the calcination of lime, i.e., the calcination process performed during clinker production. Now-adays, the Intergovernmental Panel on Climate Change (IPCC) Guidelines for National Greenhouse Gas (GHG) Inventories to report the GHG emissions do not include any calculation procedure to consider the mortar and concrete carbonation. However, the Intergovernmental Panel on Climate Change (IPCC)'s Sixth Assessment Report (AR6) recognizes the physico-chemical process known as carbonation. Brazilian net carbon dioxide emissions of cements produced from 1990 to 2019 are estimated considering the carbon dioxide uptake during the service-life and end-of-life and secondary usage stages (Tier 1). This is a fundamental scientific and technological novelty that changes the current approach to estimate the carbon dioxide emissions due to the Portland cement clinker production. Even considering the relative novelty of this approach, it should be promoted in the future and included in the national inventory report (NIR). The carbon dioxide uptake by mortar and concrete carbonation for 30 years is about 140 million tons. Within this thirty-year period about 483 million tons have been released due to the calcination process. [ABSTRACT FROM AUTHOR]

The increasing utilization of fossil fuels and industrial activities has resulted in a surge of CO2 emissions, which have significantly impacted global climate change. Carbon capture and utilization technologies offer a promising solution to decrease atmospheric CO2 concentrations and convert CO2 into valuable products. This study focuses on the capture and storage of CO2 through the mineralization of magnesium‐containing materials. The analysis encompasses the mineralization process of solid and liquid minerals, the various mineralization processes of magnesium‐containing minerals categorized as direct and indirect mineralization, and the latest research advancements in magnesium‐containing minerals. Brine and seawater from salt lakes are considered the most appropriate materials for mineralization due to their abundance and the simplicity of the process compared to solid mineralization. This paper analyzes the impact of temperature, impurity ions, additives, and microorganisms on the process of magnesium carbonate synthesis crystallization. The use of magnesium‐containing materials for carbon dioxide sequestration can effectively reduce carbon emission. The review offers guidance on carbon dioxide mineralization and explores the potential applications of magnesium mineralization. [ABSTRACT FROM AUTHOR]

National targets for CO 2 reduction in the German building sector have stagnated due to low refurbishment rates. This paper proposes an alternative approach using highly efficient, decentralized energy systems. By combining photovoltaic (PV) systems and combined heat and power (CHP) plants controlled by a modified hierarchical control algorithm, CO 2 emissions can be reduced. Results from a single-family home show a 13% CO 2 reduction with only 11% higher operational costs on heating days. On summer days, up to 50% CO 2 emissions can be avoided without additional costs. The control algorithm easily adapts to changing input parameters, making it suitable for different countries and business cases. Overall, with its modified control, the PV-CHP hybrid system can effectively reduce CO 2 emissions and adapt to varying conditions. The control can be easily used for other energy systems, like fuel cells or heat pumps. [ABSTRACT FROM AUTHOR]

Global warming due to greenhouse gas emissions has led to record-breaking heat waves, torrential rains and droughts on a global scale in recent years. For this reason, people around the world are more keenly aware of the need to reduce greenhouse gas emissions. The construction industry is one of these sources of greenhouse gas emissions. A lot of ground improvement techniques have been developed and applied to improve the physical and mechanical properties of soil in order to achieve stability improvement, ground settlement control, reinforcement, liquefaction prevention, etc. These techniques use a lot of natural materials such as sand and crushed stone and industrial products such as cement. In order to reduce their environmental impact and to economize these techniques, many kinds of industrial waste and by-products have been beneficially used in many types of ground improvement techniques. In response to the growing awareness of carbon neutrality in recent years, it is necessary to further promote initiatives such as the beneficial use of the industrial materials that have been used so far and the development of new materials and construction methods to reduce carbon dioxide emissions. It is expected that various biomass materials will be applied in ground improvement techniques to enhance "negative emission technology". In this paper, recent developments and applications of certain sorts of environmentally friendly ground improvement techniques, soil densification techniques and soil stabilization techniques are briefly introduced. It is to be expected that these will be further developed and applied to contribute to the reduction in carbon dioxide emissions. [ABSTRACT FROM AUTHOR]

Legislation regulating the sustainability requirements for hydrogen technologies relies more and more on life cycle assessments (LCAs). Due to different scopes and development processes, different pieces of EU legislation refer to different LCA methodologies, with differences in the way multifunctional processes (i.e., co-productions, recycling, and energy recovery) are treated. These inconsistencies arise because incentive mechanisms are not standardized across sectors, even though the end product, hydrogen, remains the same. The goal of this paper is to compare the life-cycle greenhouse gas (GHG) emissions of hydrogen from four production pathways depending on the multifunctional approach prescribed by the different EU policies (e.g., using substitution or allocation). The study reveals a large variation in the LCA results. For instance, the life-cycle GHG emissions of hydrogen co-produced with methanol is found to vary from 1 kg CO 2 -equivalent/kg H 2 (when mass allocation is considered) to 11 kg CO 2 -equivalent/kg H 2 (when economic allocation is used). These inconsistencies could affect the market (e.g., hydrogen from a certain pathway could be considered sustainable or unsustainable depending on the approach) and the environment (e.g., pathways that do not lead to a global emission reduction could be promoted). To mitigate these potential negative effects, we urge for harmonized and strict guidelines to assess the life-cycle GHG emissions of hydrogen technologies in an EU policy context. Harmonization should cover international policies too, to avoid the same risks when hydrogen will be traded based on its GHG emissions. The appropriate methodological approach for each production pathway should be chosen by policymakers in collaboration with the LCA community and stakeholders from the industry based on the potential market and environmental consequences of such choice. • LCA methodologies for hydrogen-related policies are currently not fully harmonized. • Four hydrogen production pathways involving multifunctionality were analysed. • GHG emissions of hydrogen vary significantly with the LCA methodology adopted. • Inconsistencies can lead to market distortions, inefficiencies, and confusion. • There is an urgent need for harmonized and strict LCA guidelines for H2 production. [ABSTRACT FROM AUTHOR]

This paper provides an educational tool to help the public better understand the greenhouse gas (GHG) emissions from the food they choose to eat on a daily basis. Using balloons filled with the representative volume of GHGs emitted through the growth, harvest, production, and transportation of various food choices, participants are able to visualize the impact of their food choices without the burden of analyzing a graph or table. Additionally, displaying the typical GHG metric of equivalent kilograms of carbon dioxide (kg CO2e) in the volume this gas would occupy at standard pressure and temperature allows for greater clarity in these results. Distribution methods for this visualization tool described herein range from science classrooms to Science, Technology, Engineering, and Mathematics (STEM) outreach events and to restaurants and grocery stores. Several tools are provided as part of this research, including a spreadsheet that incorporates these calculations, presentation slides, a worksheet for the in-class method, and poster images for eateries. For each method, participants are asked to select a protein, vegetable, and starch option to fill their plate and the resulting GHG volume is then calculated based on their selections. This provides context and allows for discussion and reshaping of our contributions to climate change. [ABSTRACT FROM AUTHOR]

Drainage for forestry purposes changes the conditions in the peat and leads to increased growth of shrubs and trees. Concurrently, the production and uptake of the greenhouse gases carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) are likely to change: due to the accelerated decomposition of oxic peat, drained peatlands are generally considered to loose peat carbon (C). We measured CO2 exchange with the eddy covariance (EC) method above a drained nutrient-poor peatland forest in Southern Finland for 16 months in 2004-2005. The site, classified as a dwarf-shrub pine bog, had been ditched about 35 years earlier. CH4 and N2O fluxes were measured at 2-5 week intervals with the chamber technique. Drainage had resulted in a relatively little change in the water table level, being on average 40 cm below the ground in 2005. The annual net ecosystem exchange was -870 g CO2 m-2 yr-1 in the calendar year 2005, varying from -810 to -900 g CO2 m-2 yr-1 during the 16 month period under investigation. The site was a small sink of CH4 (-0.12 g CH4 m-2 yr-1) and a small source of N2O (0.10 g N2O m-2 yr-1). Photosynthesis was detected throughout the year when the air temperature exceeded -3 °C. As the annual accumulation of C in the above and below ground tree biomass (550 g CO2 m-2) was significantly less than the net exchange of CO2, about 300 g CO2 m-2 yr-1 (~80 g C m-2) was likely to have accumulated as organic matter into the peat soil. This is a higher average accumulation rate than previously reported for natural northern peatlands, and the first time C accumulation has been shown, by EC measurements, to occur in a drained peatland. Our results suggest that forestry-drainage may significantly increase the CO2 uptake rate of nutrient-poor peatland ecosystems. [ABSTRACT FROM AUTHOR]

In the last two decades many scientific papers and reports have been published in the field of the application of the CO2 as a refrigerant for refrigeration systems and heat pumps. Special attention has been paid to the transcritical cycle. However, almost no papers discussed such cycles for hot climates, i. e., when the temperature of the environment is higher than 40 °C during a long period of time. This paper deals with the energetic and exergetic evaluation of a CO2 refrigeration system operating in a transcritical cycle under hot climatic conditions. The performance and exergy efficiency of the CO2 refrigeration system depend on the operation conditions. The effect of varying these conditions is also investigated as well as the limitations associated with these conditions. [ABSTRACT FROM AUTHOR]

Surface water pCO2 and pCH4 measurements were made in Québec (Canada) during consecutive seasons from 2006 to 2008 in two boreal reservoirs and nearby lakes. The goal of this follow-up was to evaluate greenhouse gas emissions from the water bodies studied, through flux calculations using the Thin Boundary Layer Model. Our measurements underscored the winter CO2 accumulation due to ice cover and the importance of a reliable estimation of spring diffusive emissions as the ice breaks up. We clearly demonstrated that in our systems, CH4 diffusive fluxes (in terms of CO2 equivalent) were of minor importance in the GHG emissions, with CO2 diffusive fluxes generally representing more than 95% of the annual diffusive fluxes. We also noted the extent of CO2 spring diffusive emissions (16% to 52%) in the annual budget. [ABSTRACT FROM AUTHOR]

With the popularization of natural gas and the requirements for environmental protection, the development and utilization of natural gas is particularly important. The status of natural gas in China's oil and gas exploration and development is constantly improving, and the country is paying more and more attention to the exploitation and utilization of natural gas. The Upper Paleozoic tight sandstone in the Ordos Basin is characterized by low porosity, low permeability and a large area of concealed gas reservoirs. By injecting carbon dioxide into the formation, the recovery rate of natural gas can be improved, and carbon neutrality can be realized by carbon sequestration. Injecting greenhouse gases into gas reservoirs for storage and improving recovery has also become a hot research issue. In order to improve the recovery efficiency of tight sandstone gas reservoirs, this paper takes the complex tight sandstone of the Upper Paleozoic in the Ordos Basin as the research object; through indoor physical simulation experiments, carried out the influence of displacement rate, fracture dip angle, core permeability, core dryness and wetness on CO2 gas displacement efficiency and storage efficiency; and analyzed the influence of different factors on gas displacement efficiency and storage efficiency to improve the recovery and storage efficiency. The research results show that under different conditions, when the injection pore volume is less than 1 PV, the relationship between the CH4 recovery rate and the CO2 injection pore volume is linear, and the tilt angle is 45°. When the injection pore volume exceeds 1 PV, the CH4 recovery rate increases slightly with the increase in displacement speed, the recovery rate of CO2 displacement CH4 is between 87–97% and the CO2 breakthrough time is 0.7 PV–0.9 PV. In low-permeability and low-speed displacement cores, the diffusion of carbon dioxide molecules is more significant. The lower the displacement speed is, the earlier the breakthrough time is, and the final recovery of CH4 slightly decreases. Gravity has a great impact on carbon sequestration and enhanced recovery. The breakthrough of high injection and low recovery is earlier, and the recovery of CH4 is about 3.3% lower than that of low injection and high recovery. The bound water causes the displacement phase CO2 to be partially dissolved in the formation water, and the breakthrough lags about 0.1 PV. Ultimately, the CH4 recovery factor and CO2 storage rate are higher than those of dry-core displacement. The research results provide theoretical data support for CO2 injection to improve recovery and storage efficiency in complex tight sandstone gas reservoirs. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) emissions from burning fossil fuels play a crucial role in global warming/climate change. The effective removal of CO2 from the point sources or atmosphere (CO2 capture), its conversion to value-added products (CO2 utilization), and long-term geological storage, or CO2 sequestration, has captured the attention of several researchers and policymakers. This review paper illustrates all kinds of CO2 capture/separation processes and the challenges faced in deploying these technologies. This review described the research efforts put forth in gas separation technologies. Recent advances in the existing gas separation technologies have been highlighted, and future directives for commercial deployment have also been outlined. [ABSTRACT FROM AUTHOR]

The emission of greenhouse gases, especially carbon dioxide, accelerates global warming and poses a crisis to the environment and human society. The carbon emission of products is mainly determined by the design stage of the life cycle. However, the data in the scheme design stage has certain fuzziness and uncertainty. Therefore, it is difficult to calculate the carbon footprint directly. In this paper, a carbon footprint prediction model of linkage mechanism scheme design stage (CFPL-SDS) is proposed to help designers make decisions. Firstly, the CFPL-SDS is built to quantify the carbon performance of linkage mechanism. Secondly, according to the structural characteristics of the closed-loop cascade rehabilitation robot, a four-finger training mechanism is designed. Finally, the model is applied to the four-finger training mechanism to verify its feasibility. The results show that the CFPL-SDS can calculate the carbon footprint of the linkage in the design stage. Moreover, the CFPL-SDS establishes the mathematical model foundation for the low-carbon optimization problem of linkage mechanism. [ABSTRACT FROM AUTHOR]

The emission of greenhouse gases (GHG), particularly carbon dioxide (CO2), within the atmosphere poses serious threats to society and the environment. In this paper, we examine the effect of carbon dioxide (CO2) emissions on the association between corporate social responsibility (CSR) and stock valuation. Using a sample of listed non‐financial US firms from 2002 through 2018, we find that CO2 emission plays a moderating role in reshaping the CSR‐stock valuation nexus. Further analysis showed that our results are robust for using alternate proxies of CSR, CO2, additional control and methods to alleviate endogeneity concerns. Additionally, we explored how increasing carbon footprints reshape this association only for firms with strong governance structures. Overall, our results indicate that the positive impact of CSR on stock valuation is overlaid by corporate CO2 emission. The practical and theoretical insights of this study were explored. [ABSTRACT FROM AUTHOR]

Carbon dioxide is the largest component of the human footprint and one of the major components of all greenhouse gases. The expected increase in population will lead to growth in energy consumption and greenhouse gas emissions. The building industry has the highest potential for reducing greenhouse gas emissions. Therefore, buildings should become not only efficient consumers but also energy producers, not a simple task in dense cities. The paper describes the feasibility and limitations of near zero energy design in highly dense urban conditions. The study was carried out by examination and comparison of various density design, alternatives of an existing urban plot in the coastal climate zone of Israel. Increased dwelling units' number leads to higher total energy use on the one hand and mutual shading of new high-rise residential buildings on the other. Preserving solar rights for PV systems installation become more complex. The relation between urban density and solar rights in urban design, energy consumption and energy generation within plot borders and their implications are presented and discussed in the paper. [ABSTRACT FROM AUTHOR]

Agriculture is the leading sector that is responsible for global climate change through its significant contribution to greenhouse gas (GHG) emissions. Intriguingly, sub-Saharan Africa (SSA) is experiencing higher temperatures and lesser rainfall due to climate change enhanced by anthropogenic GHG emissions. Agriculture and energy use in the SSA predominantly influence the anthropogenic GHG leading to global warming. Therefore, reducing agricultural GHG emissions (such as carbon dioxide, nitrous oxide, and methane) plays a significant role in climate change adaptation. This paper reviews the potential implication of agriculture and energy use on climate change and its implications on environmental sustainability in SSA. Herewith, we explored various GHGs emitted through agriculture-energy use, their effects on climate change, as well as several climate change adaptation mechanisms, and gaps in existing knowledge that necessitate more research, were also explored. We found that agriculture had negative implications on climate change impacts in the SSA countries and that a more focused strategy that is both economically and technically feasible in terms of preferences for land use, effective energy use, and food supply would aid in GHG emission reduction and environmental sustainability. Adapting to the projected changes in the short term while investing in long-term mitigation strategies might be the only way toward a sustainable environment in this region. [ABSTRACT FROM AUTHOR]

Carbon capture, utilization, and storage (CCUS) technology is considered an effective way to reduce greenhouse gases, such as carbon dioxide (CO2), which is significant for achieving carbon neutrality. Based on Derwent patent data, this paper explored the technology topics in CCUS patents by using the latent Dirichlet allocation (LDA) topic model to analyze technology's hot topics and content evolution. Furthermore, the logistic model was used to fit the patent volume of the key CCUS technologies and predict the maturity and development trends of the key CCUS technologies to provide a reference for the future development of CCUS technology. We found that CCUS technology patents are gradually transforming to the application level, with increases in emerging fields, such as computer science. The main R&D institutes in the United States, Europe, Japan, Korea, and other countries are enterprises, while in China they are universities and research institutes. Hydride production, biological carbon sequestration, dynamic monitoring, geological utilization, geological storage, and CO2 mineralization are the six key technologies of CCUS. In addition, technologies such as hydride production, biological carbon sequestration, and dynamic monitoring have good development prospects, such as CCUS being coupled with hydrogen production to regenerate synthetic methane and CCUS being coupled with biomass to build a dynamic monitoring and safety system. [ABSTRACT FROM AUTHOR]

This paper investigates the nexus between greenhouse gas emissions and poverty alleviation in the Economic Commission of West African States between 1985 and 2020 applying autoregressive distributed lag and Granger causality techniques. The results reveal that carbon dioxide non‐significantly relates to gross domestic product per capita positively while nitrous oxide and foreign direct investment impacts gross domestic product per capita positively. Methane negatively impacts gross domestic product per capita. The governments should use conventions to regulate greenhouse gas emissions' effects on environmental degradation regionally and globally. The study underscores that countries should diversify to cleaner energy sources. This would reduce greenhouse gas emissions in the atmosphere. Massive technological investment is required to mitigate the greenhouse gas emissions' negative impacts on the environment which create poverty. This policy implication ensures environmental sustainability and reverses the ugly trend of greenhouse gas emissions on poverty. [ABSTRACT FROM AUTHOR]

Climate change, one of the biggest threat of global life, is continuously triggered by greenhouse gases released into the atmosphere due to human activities. Carbon dioxide (CO2), one of the most important greenhouse gases, has revealed the concept of carbon footprint, and efforts to take mitigation measures by calculating it have become widespread. With sustainable campus studies, universities, where science and innovations are created, lead other institutions by creating the necessary database for measuring and managing greenhouse gas (GHG) emissions and calculating the corporate carbon footprint. This study calculated and compared the carbon footprints of Sakarya University Esentepe Campus for 2019 and 2020 when distance education was carried out during the Covid-19 pandemic. Greenhouse gas emissions resulting from activities on campus were calculated and converted to a CO2 equivalent. GHG emission factors and the Tier-1 method of the Intergovernmental Panel on Climate Change (IPCC) were used in the calculations. As a result,the carbon footprint was 13273.38 tCO2e in 2019 and 6338.72 tCO2e in 2020. It was determined that the largest share of carbon emissions was due to the use of electrical energy. The results obtained for both years were compared, and a 47.7% reduction in total emissions was evaluated. In the light of current studies on carbon emission reduction, suggestions and measures need to be taken are summarized in this research. [ABSTRACT FROM AUTHOR]

Savanna ecosystems are subject to accelerating land use change as human demand for food and forest products increases. Land use change has been shown to both increase and decrease greenhouse gas fluxes from savannas and considerable uncertainty exists about the non-CO2 fluxes from the soil. We measured methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) over a complete wet-dry seasonal cycle at three replicated sites of each of three land uses: savanna, young pasture and old pasture (converted from savanna 5-7 and 25-30 yr ago, respectively) in the Douglas Daly region of northern Australia. The effect of break of season rains at the end of the dry season was investigated with two irrigation experiments. Land use change from savanna to pasture increased net greenhouse gas fluxes from the soil. Pasture sites were a weaker sink for CH4 than savanna sites and, under wet conditions, old pastures turned from being sinks to a significant source of CH4. Nitrous oxide emissions were generally very low, in the range of 0 to 5 µg N2O-N m-2 h-1, and under dry conditions soil uptake of N2O was apparent. Break of season rains produced a small, short lived pulse of N2O up to 20 µg N2O-N m-2 h-1, most evident in pasture soil. Annual cumulative soil CO2 fluxes increased after clearing, with savanna (14.6 t CO2-C ha-1 yr-1) having the lowest fluxes compared to old pasture (18.5 t CO2-C ha-1 yr-1) and young pasture (20.0 t CO2-C ha-1 yr-1). Clearing savanna increased soil-based greenhouse gas emissions from 53 to ~70 t CO2-equivalents, a 30% increase dominated by an increase in soil CO2 emissions and shift from soil CH4 sink to source. Seasonal variation was clearly driven by soil water content, supporting the emerging view that soil water content is a more important driver of soil gas fluxes than soil temperature in tropical ecosystems where temperature varies little among seasons. [ABSTRACT FROM AUTHOR]

Oxygen minimum zones (OMZs), known as suboxic layers mainly localized in the Eastern Boundary Upwelling Systems, are expanding since the 20th "high CO2" century, probably due to the global warming. OMZs are also known to contribute significantly to the oceanic production of N2O, a greenhouse gas (GHG) more efficient than CO2. However, the contribution of the OMZs on the oceanic sources and sinks budget of CO2, the main GHG, still remains to be established. We present here the dissolved inorganic carbon (DIC) structure, associated locally with the Chilean OMZ and globally with the main most intense OMZs (O2<20 μmol/kg) in the open ocean. To achieve this, we jointly examine simultaneous DIC and O2 data collected off Chile during 4 cruises and a monthly monitoring (2000-2002) in one of the shallowest OMZ, along with international DIC and O2 databases for other OMZs. High DIC concentrations (>2225 μmol/kg, up to 2350 μmol/kg) have been reported over the whole OMZ thickness, allowing to define for all studied OMZs a Carbon Maximum Zone (CMZ). The CMZs-OMZs constitute the largest carbon reserves of the ocean in subsurface waters and could induce a positive feedback for the atmosphere during upwelling activity, as potential direct local sources of CO2. The CMZ paradoxically presents a slight "carbon deficit" in its core, meaning a DIC increase from the oxygenated ocean to the OMZ lower than the corresponding O2 decrease (assuming classical C/O molar ratios). This "carbon deficit" would be related to thermal mechanisms affecting faster O2 than DIC (due to the carbonate buffer effect) and occurring upstream in warm waters (e.g., in the Equatorial Divergence), where the CMZ-OMZ core originates. The "carbon deficit" in the CMZ core would be mainly compensated locally at the oxycline, by a "carbon excess" induced by a specific remineralization. Indeed, a possible co-existence of bacterial heterotrophic and autotrophic processes usually occurring at different depths could stimulate an intense aerobic-anaerobic remineralization, inducing deviation of C/O molar ratio from the canonical Redfield ratios. Further studies to confirm these results for all OMZs are required to understand the OMZ effects on both climatic feedback mechanisms and marine ecosystem perturbations. [ABSTRACT FROM AUTHOR]

Following China and the United States, India is the third highest CO2 emitter in the world. With its fast rising population and an industry primarily reliant on coal and oil, the country's emissions will continue to rise unless appropriate measures are taken. In India generally the carbon sequestration is done by storing CO2 in sedimentary basins where it gets capped by the impermeable cap rocks. The study aims to unfold the other techniques of carbon sequestration in subsurface formations, except for narrating the different types of carbon capture and sequestration techniques along with its storage in different types of environments. For instance, abiotic and biotic environments for CO2 sequestration. It further talks about carbon injections of oceanic, geological, and terrestrial types, to name just a few. Types of carbon emission sources are discussed too. In this paper three different approaches are described for carbon mitigation, namely CarbFix, CO2 Plume technology and Carbon Trading. A prefeasibility study was done in order to implement the three techniques in Dholera geothermal region in Gujarat, India. In literature review, it can be seen how the three techniques can help in permanent mitigation of captured carbon through carbonate mineralization, power generation and industrial applications. For any project government and public participation is important. In this regard the study gives a brief understanding about the steps to be taken by government and the public to promote such projects for carbon mitigation. Besides, the steps to be taken in such projects for health and risk assessment were talked about in literature review too. [ABSTRACT FROM AUTHOR]