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In an exploration of environmental concerns, this groundbreaking research delves into the relationship between GDP per capita, coal rents, forest rents, mineral rents, oil rents, natural gas rents, fossil fuels, renewables, environmental tax and environment-related technologies on CO 2 emissions in 30 highly emitting countries from 1995 to 2021 using instrumental-variables regression Two-Stage least squares (IV-2SLS) regression and two-step system generalized method of moments (GMM) estimates. Our results indicate a significant positive relationship between economic growth and CO 2 emissions across all quantiles, showcasing an EKC with diminishing marginal effects. Coal rents exhibit a statistically significant negative relationship with emissions, particularly in higher quantiles, and mineral rents show a negative association with CO 2 emissions in lower and middle quantiles, reinforcing the idea of resource management in emissions reduction. Fossil fuels exert a considerable adverse impact on emissions, with a rising effect in progressive quantiles. Conversely, renewable energy significantly curtails CO 2 emissions, with higher impacts in lower quantiles. Environmental tax also mitigates CO 2 emissions. Environment-related technologies play a pivotal role in emission reduction, particularly in lower and middle quantiles, emphasizing the need for innovative solutions. These findings provide valuable insights for policymakers, highlighting the importance of tailoring interventions to different emission levels and leveraging diverse strategies for sustainable development., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This research paper delves into the intricate interplay between decarbonisation and sustainability, focusing on adopting chemical looping technologies. Deep decarbonisation scenarios necessitate a profound transformation in various sectors to mitigate climate change, and oil refineries, as pivotal players, must adapt to these changes. Employing the BLUES integrated assessment model, we evaluate the evolution of the refining sector in decarbonisation pathways, emphasising its potential for sustainability through repurposing and emissions mitigation. Additionally, we delve into chemical looping technologies, including Solar Thermal Chemical Looping (STCL), Reverse Water Gas Shift Chemical Looping (RWGS-CL), Chemical Looping Reforming (CLR), and Super Dry Reforming (SDR), elucidating their principles and contributions to carbon dioxide (CO 2 ) conversion. These technologies offer promising routes for CO 2 capture and present opportunities for sustainable carbon loop cycles, potentially revolutionising industries' emissions reduction efforts. In a world of climate change, this research illuminates a sustainable path forward by integrating decarbonisation and innovative CO 2 management strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing for financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Mollisols rich in natural organic matter are a significant sink of carbon (C) and selenium (Se). Climate warming and agricultural expansion to the cold Mollisol regions may enhance soil respiration and biogeochemical cycles, posing a growing risk of soil C and Se loss. Through field-mimicking incubation experiments with uncultivated and cultivated soils from the Mollisol regions of northeastern China, this research shows that soil respiration remained significant even during cold seasons and caused co-emission of greenhouse gases (CO 2 and CH 4 ) and methylated Se. Such stimulus effects were generally stronger in the cultivated soils, with maximum emission rates of 7.45 g/m 2 /d C and 1.42 μg/m 2 /d Se. For all soil types, the greatest co-emission of CO 2 and dimethyl selenide occurred at 25 % soil moisture, whereas measurable CH 4 emission was observed at 40 % soil moisture with higher percentages of dimethyl diselenide volatilization. Molecular characterization with three-dimensional fluorescence and ultra-high resolution mass spectrometry suggests that CO 2 emission is sensitive to the availability of microbial protein-like substances and free energy from organic carbon biodegradation under variable moisture conditions. Predominant Se binding to biodegradable organic matter resulted in high dependence of Se volatilization on rates of greenhouse gas emissions. These findings together highlight the importance of dynamic organic carbon quality for soil respiration and consequent Mollisol Se loss risk, with implications for science-based management of C and Se resources in agricultural lands to combat with Se deficiency., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

This study investigates the impact of public-private partnerships investment in energy and FDI on environmental quality in global investment countries during 1995-2018. Economic growth, technological innovations and consumption of clean energy are also considered as additional determinants of environmental quality. The study applied advanced panel econometric models. Our empirical results affirm the evidence of a long-run association between environmental quality and its determinants. Specifically, economic growth as well as clean energy use improves quality of environment by lowering carbon emissions. Public-private partnerships investment in energy, FDI and technological innovations decrease carbon emissions. Energy consumption (generated from fossil fuel) increases carbon emissions. Heterogeneous causality evidence indicates the presence of a unidirectional causality relation from carbon emissions to public-private partnerships investment in energy and a feedback causality occurs between consumption of clean energy and CO 2 emissions. This empirical evidence provides new insights for both policymakers and governments to support public-private partnership investments in energy for the improvement of quality of environment in global investment countries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The CO 2 bioelectromethanosynthesis via two-chamber microbial electrolysis cell (MEC) holds tremendous potential to solve the energy crisis and mitigate the greenhouse gas emissions. However, the membrane fouling is still a big challenge for CO 2 bioelectromethanosynthesis owing to the poor proton diffusion across membrane and high inter-resistance. In this study, a new MEC bioreactor with biogas recirculation unit was designed in the cathode chamber to enhance secondary-dissolution of CO2 while mitigating the contaminant adhesion on membrane surface. Biogas recirculation improved CO 2 re-dissolution, reduced concentration polarization, and facilitated the proton transmembrane diffusion. This resulted in a remarkable increase in the cathodic methane production rate from 0.4 mL/L·d to 8.5 mL/L·d. A robust syntrophic relationship between anodic organic-degrading bacteria (Firmicutes 5.29%, Bacteroidetes 25.90%, and Proteobacteria 6.08%) and cathodic methane-producing archaea (Methanobacterium 65.58%) enabled simultaneous organic degradation, high CO 2 bioelectromethanosynthesis, and renewable energy storage., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Microbial electrosynthesis (MES) is an electrically driven technology that can be used for converting CO/CO 2 into chemicals. The unique electronic and substrate properties of CO make it an important research target for MES. However, CO can poison the cathode and increase the overpotential of hydrogen evolution reaction (HER), thus reducing the electron transfer rate via H 2 . This work evaluated the effect of an anti-CO HER catalyst on the performance of MES for CO/CO 2 conversion. ZnMo-metal-organic framework (MOF) materials with different calcination temperatures were synthesized. ZnMo-MOF-800 with Mo 2 C nanoparticles as active centers exhibited excellent resistance to CO toxicity. It also obtained the highest hydrogen evolution and enhanced electron transfer rate in CO atmosphere. MES with ZnMo-MOF-800 cathode and Clostridium ljungdahlii as biocatalyst obtained 0.31 g L -1  d -1 acetate yield, 0.1 g L -1  d -1 butyrate yield, and 0.09 g L -1  d -1 2,3-butanediol yield in CO/CO 2 , while Pt/C only get 0.076 g L -1  d -1 acetate yield, 0.05 g L -1  d -1 butyrate yield and 0.02 g L -1  d -1 2,3-butanediol yield. ZnMo-MOF-800 was conducive to biofilm formation, enabling it to better resist CO toxicity. This work provides new opportunities for constructing a highly efficient cathode with an anti-CO hydrogen evolution catalyst to enhance CO/CO 2 conversion in MES., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Carbon dioxide (CO 2 ) production and emissions from inland waters play considerable roles in global atmospheric CO 2 sources, while there are still uncertainties regarding notable nutrient inputs and anthropogenic activities. Urban inland waters, with frequently anthropogenic modifications and severely nitrogen loadings, were hotspots for CO 2 emissions. Here, we investigated the spatiotemporal patterns of partial pressure of CO 2 (pCO 2 ) and CO 2 fluxes (FCO 2 ) in typical urban inland waters in Tianjin, China. Our observation indicated that pCO 2 values were oversaturated in highly polluted waters, particularly in sewage rivers and urban rivers, exhibiting approximately 9 times higher than the atmosphere equilibrium concentration during sampling campaigns. Obviously, the spatiotemporal distributions of pCO 2 and FCO 2 emphasized that the water environmental conditions and anthropogenic activities jointly adjusted primary productivity and biological respiration of inland waters. Meanwhile, statistically positive correlations between pCO 2 /FCO 2 and NH 4 + -N/NO 3 - -N (p < 0.05) suggested that nitrogen biogeochemical processes, especially the nitrification, played a dominant role in CO 2 emissions attributing to the water acidification that stimulated CO 2 production and emissions. Except for slight CO 2 sinks in waters with low organic contents, the total CO 2 emissions from the urban surface waters of Tianjin were remarkable (286.8 Gg yr -1 ). The results emphasized that the reductions of nitrogen loadings, sewage draining waters, and agricultural pollution could alleviate CO 2 emissions from urban inland waters., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

On the one hand, economies, particularly developing ones, need to grow. On the other hand, climate change is the most pressing issue globally, and nations should take the necessary measures. Such a complex task requires new theoretical and empirical models to capture this complexity and provide new insights. Our study uses a newly developed theoretical framework that involves renewable energy consumption (REC) and total factor productivity (TFP) alongside traditional factors of CO2 emissions. It provides policymakers with border information compared to traditional models, such as the Environmental Kuznets Curve (EKC), being limited to income and population. Advanced panel time series methods are also employed, addressing panel data issues while producing not only pooled but also country-specific results. 20 Renewable Energy Country Attractiveness Index (RECAI) nations are considered in this study. The results show that REC, TFP, and exports reduce CO2 emissions with elasticities of 0.3, 0.4, and 0.3, respectively. Oppositely, income and imports increase emissions with elasticities of 0.8 and 0.3. Additionally, we show that RECAI countries are commonly affected by global and regional factors. Moreover, we find that shocks can create permanent changes in the levels of the factors but only temporary changes in their growth rates. The main policy implication of the findings is that authorities should implement measures boosting TFP and REC. These factors are driven mainly by technological progress, innovation, and efficiency gains. Thus, they can simultaneously reduce emissions while promoting long-run green economic growth, which addresses the complexity mentioned above to some extent., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Introduction: The level of atmospheric CO 2 has continuously been increasing and the resulting greenhouse effects are receiving attention globally. Carbon removal from the atmosphere occurs naturally in various ecosystems. Among them, saline environments contribute significantly to the global carbon cycle. Carbonate deposits in the sediments of salt lakes are omnipresent, and the biological effects, especially driven by halophilic microalgae and bacteria, on carbonate formation remain to be elucidated., Objectives: The present study aims to characterize the carbonates formed in saline environments and demonstrate the mechanisms underlying biological-driven CO 2 removal via microalgal-bacterial consortium., Methods: The carbonates naturally formed in saline environments were collected and analyzed. Two saline representative organisms, the photosynthetic microalga Dunaliella salina and its mutualistic halophilic bacteria Nesterenkonia sp. were isolated from the inhabiting saline environment and co-cultivated to study their biological effects on carbonates precipitation and isotopic composition. During this process, electrochemical parameters and Ca 2+ flux, and expression of genes related to CaCO 3 formation were analyzed. Genome sequencing and metagenomic analysis were conducted to provide molecular evidence., Results: The results showed that natural saline sediments are enriched with CaCO 3 and enrichment of genes related to photosynthesis and ureolysis. The co-cultivation stimulated 54.54% increase in CaCO 3 precipitation and significantly promoted the absorption of external CO 2 by 49.63%. A pH gradient was formed between the bacteria and algae culture, creating 150.22 mV of electronic potential, which might promote Ca 2+ movement toward D. salina cells. Based on the results of lab-scale induction and 13 C analysis, a theoretical calculation indicates a non-negligible amount of 0.16 and 2.3 Tg C/year carbon sequestration in China and global saline lakes, respectively., Conclusion: The combined effects of these two typical representative species have contributed to the carbon sequestration in saline environments, by promoting Ca 2+ influx and increase of pH via microalgal and bacterial metabolic processes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Production and hosting by Elsevier B.V.)

China proposed establishing a carbon emission trading market in its 12th Five-Year Plan to reduce carbon dioxide emissions through market mechanisms, promote the development of science and technology and help China become an environment-friendly country. To examine the impact of carbon emission trading on green technology innovation in Chinese energy enterprises, data from 1993 to 2020 were collected from 494 A-share-listed energy enterprises. Enterprises located in the pilot area of carbon emissions trading were assigned to the treatment group, while those in the non-pilot area were assigned to the control group. The propensity-score-matching method was utilized to match the treatment group with the control group, and the resulting samples were used as the actual sample data. The difference-in-differences method was then employed to assess the net impact of carbon emission trading and investigate its effect on green technology innovation in energy enterprises. This empirical study suggested that carbon emission trading has a positive impact on green technology innovation in energy enterprises, particularly state-owned ones. Larger enterprises are more willing to engage in green technological innovation than small enterprises. Furthermore, when faced with a carbon emission trading system, 'mature' companies tend to pay more attention to green technology innovation than younger enterprises do. This study puts forward policy measures for establishing a national-level carbon emission market in China in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

To achieve net-zero emissions by 2050, we need economic means of sequestering carbon dioxide (CO 2 ) and reducing greenhouse gas emissions (GHG). We analyze the sequestration potential of the Intermountain West (I-West) region, US, as a primary energy transition hub through analysis of wellbore retrofit potential and emission reduction in both fugitive gas abatement and flare gas. We selected the I-West region due to its abundant energy sources and oil and gas production legacy. Preliminary analysis hints that well retrofits can breathe new life into a well at a fraction of the cost of a new drill. With millions of potential candidates in the US, even a modest fraction (1% or less) suitable for retrofit could accelerate the shift to large-scale CO 2 sequestration. Fugitive gas, the unintentional release of wellbore gases such as methane, is a significant emissions source. Through conservative analysis, it is estimated that wellhead leakage alone may account for 5 million tonnes of carbon dioxide equivalent (CO 2 e) emissions. We conclude by assessing the CO 2 emissions from flaring, which is the burning of associated gas during well operations, conservative analysis indicates flaring contributes another 2 million tonnes of CO 2 emissions to the region. We find that with targeted retrofit and better controls on emissions sources, the I-West region can make a significant impact in the nation's push to become net-zero. This study outlines economic feasibility and actionable items to achieve the critical reductions in emissions and increases in sequestration necessary to attain net zero., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

Mass transfer in liquid phase is the rate-limiting step for carbon dioxide capture by ammonia water, which results in a low total mass transfer coefficient and thus a poor carbon dioxide removal efficiency. For this issue, this study established a venturi reactor with an excellent mass transfer performance to promote mass transfer rate during carbon dioxide capture, and investigated the effect of operating parameters of the venturi reactor on carbon dioxide removal efficiency and overall mass transfer coefficient. The results showed that with an increasing flow rate of the jet from 8.31 to 12.73 L/min, the carbon dioxide removal efficiency decreased due to the increase of flow rate of flue gas, and the changing trend of overall mass transfer coefficient gradually transited from increasing to decreasing with the extension of reaction time. The carbon dioxide removal efficiency and the overall mass fraction coefficient increased upon the increase of ammonia concentration from 0.1 wt% to 0.75 wt%. With the increase of inlet carbon dioxide concentration from 7% to 19%, the carbon dioxide removal efficiency and the overall mass transfer coefficient decreased. Venturi reactor was of a fast mass transfer rate during carbon dioxide capture, and the maximum CO 2 removal efficiency was 96.4% at ammonia concentration of 0.75 wt%, CO 2 volume concentration of 15%, flow rate of jet of 8.36 L/min. This study provided a theoretical value for the development of venturi reactor for carbon dioxide capture., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

GeoCARB is a proposed instrument to measure column averaged concentrations of CO2, CH4 and CO from geostationary orbit using reflected sunlight in near-infrared absorption bands of the gases. The scanning options, spectral channels and noise characteristics of geoCARB and two descope options are described. The accuracy of concentrations from geoCARB data is investigated using end-to-end retrievals; spectra at the top of the atmosphere in the geoCARB bands are simulated with realistic trace gas profiles, meteorology, aerosol, cloud and surface properties, and then the concentrations of CO2, CH4 and CO are estimated from the spectra after addition of noise characteristic of geoCARB. The sensitivity of the algorithm to aerosol, the prior distributions assumed for the gases and the meteorology are investigated. The contiguous spatial sampling and fine temporal resolution that geoCARB could provide opens the possibility of monitoring localised sources such as power plants. Simulations of emissions from a power plant with a gaussian plume are conducted to assess the accuracy with which the emission strength may be recovered from geoCARB spectra. Scenarios for "clean" and "dirty" power plants are examined. It is found that a reliable estimate of the emission rate is possible, especially for power plants that have particulate filters, by averaging multiple snap-shots of the CO2 field surrounding the plant. The result holds even in the presence of partial cloud cover. [ABSTRACT FROM AUTHOR]

Ecosystem-scale manipulation experiments represent large science investments that require well-designed data acquisition and management systems to provide reliable, accurate information to project participants and third party users. The SPRUCE Project (Spruce and Peatland Responses Under Climatic and Environmental Change, http: //mnspruce.ornl.gov) is such an experiment funded by the Department of Energy's (DOE), Oce of Science, Terrestrial Ecosystem Science (TES) Program. The SPRUCE experimental mission is to assess ecosystem-level biological responses of vulnerable, high carbon terrestrial ecosystems to a range of climate warming manipulations and an elevated CO2 atmosphere. SPRUCE provides a platform for testing mechanisms controlling the vulnerability of organisms, biogeochemical processes, and ecosystems to climatic change (e.g., thresholds for organism decline or mortality, limitations to regeneration, biogeochemical limitations to productivity, the cycling and release of CO2 and CH4 to the atmosphere). The SPRUCE experiment will generate a wide range of continuous and discrete measurements. To successfully manage SPRUCE data collection, achieve SPRUCE science objectives, and support broader climate change research, the research staff has designed a flexible data system using proven network technologies and software components. The primary SPRUCE data system components are: 1. Data acquisition and control system - set of hardware and software to retrieve biological and engineering data from sensors, collect sensor status information, and distribute feedback to control components. 2. Data collection system - set of hardware and software to deliver data to a central depository for storage and further processing. 25 3. Data management plan - set of plans, policies, and practices to control consistency, protect data integrity, and deliver data. This publication presents our approach to meeting the challenges of designing and constructing an eficient data system for managing high volume sources of in-situ observations in a remote, harsh environmental location. The approach covers data flow starting from the sensors and ending at the archival/distribution points, discusses types of hardware and software used, examines design considerations that were used to choose them, and describes the data management practices chosen to control and enhance the value of the data. [ABSTRACT FROM AUTHOR]

The knowledge of Green House Gases GHGs fluxes at the air--sea interface at high resolution is crucial to accurately quantify the role of the ocean in the absorption and emission of GHGs. In this paper we present a novel method to reconstruct maps of surface ocean partial pressure of CO2, pCO2, and air--sea CO2 fluxes at super resolution (4 km) using Sea Surface Temperature (SST) and Ocean Colour (OC) data at this resolution, and CarbonTracker CO2 fluxes data at low resolution (110 km). Inference of super-resolution of pCO2, and air--sea CO2 fluxes is performed using novel nonlinear signal processing methodologies that prove efficient in the context of oceanography. The theoretical background comes from the Microcanonical Multifractal Formalism which unlocks the geometrical determination of cascading properties of physical intensive variables. As a consequence, a multiresolution analysis performed on the signal of the so-called singularity exponents allows the correct and near optimal cross-scale inference of GHGs fluxes, as the inference suits the geometric realization of the cascade. We apply such a methodology to the study offshore of the Benguela area. The inferred representation of oceanic partial pressure of CO2 improves and enhances the description provided by CarbonTracker, capturing the small scale variability. We examine different combinations of Ocean Colour and Sea Surface Temperature products in order to increase the number of valid points and the quality of the inferred pCO2 field. The methodology is validated using in-situ measurements by means of statistical errors. We obtain that mean absolute and relative errors in the inferred values of pCO2 with respect to in-situ measurements are smaller than for CarbonTracker. [ABSTRACT FROM AUTHOR]

Physical soil properties create lags between temperature change and corresponding soil responses, which obscure true Q10 values and other biophysical parameters such as depth of production. This study examines an inversion approach for estimating Q10 and depth of production (Zp) using physically based soil models, constrained by observed high-frequency surface fluxes and/or concentrations. Our inversion strategy uses a 1-D multi-layered soil model that simulates realistic temperature and gas diffusion. We tested inversion scenarios on synthetic data using a range of constraining parameters, time averaging techniques, mechanisms to improve computational efficiency, and various methods of incorporating real data into the model. Overall, we have found that with carefully constrained data, inversion was possible. While inversions using exclusively surface flux measurements could succeed, constraining the inversion using multiple shallow subsurface CO2 measurements proved to be most successful. Inversions constrained by these shallow measurements returned Q10 and Zp values with average errors of 1.85 and 0.16 % respectively. This work is a first step toward building a reliable framework for removing physical effects from high frequency soil CO2 data. Ultimately, we hope that this process will lead to better estimates of biophysical soil parameters and their variability on short timescales. [ABSTRACT FROM AUTHOR]

Earth surface systems are controlled by a combination of global and local factors, which cannot be understood without accounting for both the local and global components. The system dynamics cannot be recovered from the global or local controls alone. Ground forest inventory is able to accurately estimate forest carbon stocks at sample plots, but these sample plots are too sparse to support the spatial simulation of carbon stocks with required accuracy. Satellite observation is an important source of global information for the simulation of carbon stocks. Satellite remote-sensing can supply spatially continuous information about the surface of forest carbon stocks, which is impossible from ground-based investigations, but their description has considerable uncertainty. In this paper, we validated the Lund-Potsdam-Jena dynamic global vegetation model (LPJ), the Kriging method for spatial interpolation of ground sample plots and a satellite-observation-based approach as well as an approach for fusing the ground sample plots with satellite observations and an assimilation method for incorporating the ground sample plots into LPJ. The validation results indicated that both the data fusion and data assimilation approaches reduced the uncertainty of estimating carbon stocks. The data fusion had the lowest uncertainty by using an existing method for high accuracy surface modeling to fuse the ground sample plots with the satellite observations (HASM-SOA). The estimates produced with HASM-SOA were 26.1 and 28.4% more accurate than the satellite-based approach and spatial interpolation of the sample plots, respectively. Forest carbon stocks of 7.08 Pg were estimated for China during the period from 2004 to 2008, an increase of 2.24 Pg from 1984 to 2008, using the preferred HASM-SOA method. [ABSTRACT FROM AUTHOR]

Laser Absorption Spectroscopy (LAS) has been used over the last several decades for the measurement of trace gasses in the atmosphere. For over a decade, LAS measurements from multiple sources and tens of retroreflectors have been combined with sparse-sample tomography methods to estimate the 2-D distribution of trace gas concentrations and underlying fluxes from pointlike sources. In this work, we consider the ability of such a system to detect and estimate the position and rate of a single point leak which may arise as a failure mode for carbon dioxide storage. The leak is assumed to be at a constant rate giving rise to a plume with a concentration and distribution that depend on the wind velocity. We demonstrate the ability of our approach to detect a leak using numerical simulation and a preliminary measurement. [ABSTRACT FROM AUTHOR]

The annual average CO2 difference between baseline data from Mauna Loa and the southern Hemisphere increased by ~ 0.8 µmolmol-1 (0.8 ppm) between 2009 and 2010, a step unprecedented in over 50 years of reliable data. We find no evidence for coinciding, sufficiently large and rapid, source/sink changes. A statistical anomaly is unlikely due to the highly systematic nature of the variation in observations. An explanation for the step, and the subsequent 5 year stability in this north-south difference, involves inter-hemispheric atmospheric exchange variation. The selected data describing this episode provide a critical test for studies that employ atmospheric transport models that interpret global carbon budgets and inform management of anthropogenic emissions. [ABSTRACT FROM AUTHOR]

The decrease in the calorific value of refuse-derived fuel (RDF) is an unintended outcome of the progress made toward more sustainable waste management. Plastics and paper separation and recycling leads to the overall decrease in waste's calorific value, further limiting its applicability for thermal treatment. Pyrolysis has been proposed to densify energy in RDF and generate carbonized solid fuel (CSF). The challenge is that the feedstock composition of RDF is variable and site-specific. Therefore, the optimal pyrolysis conditions have to be established every time, depending on feedstock composition. In this research, we developed a model to predict the higher heating value (HHV) of the RDF composed of eight morphological refuse groups after low-temperature pyrolysis in CO2 (300–500 °C and 60 min) into CSF. The model considers cardboard, fabric, kitchen waste, paper, plastic, rubber, PAP/AL/PE (paper/aluminum/polyethylene) composite packaging pack, and wood, pyrolysis temperature, and residence time. The determination coefficients (R2) and Akaike information criteria were used for selecting the best model among four mathematical functions: (I) linear, (II) second-order polynomial, (III) factorial regression, and (IV) quadratic regression. For each RDF waste component, among these four models, the one best fitted to the experimental data was chosen; then, these models were integrated into the general model that predicts the HHV of CSF from the blends of RDF. The general model was validated experimentally by the application to the RDF blends. The validation revealed that the model explains 70–75% CSF HHV data variability. The results show that the optimal pyrolysis conditions depend on the most abundant waste in the waste mixture. High-quality CSF can be obtained from wastes such as paper, carton, plastic, and rubber when processed at relatively low temperatures (300 °C), whereas wastes such as fabrics and wood require higher temperatures (500 °C). The developed model showed that it is possible to achieve the CSF with the highest HHV value by optimizing the pyrolysis of RDF with the process temperature, residence time, and feedstock blends pretreatment. [ABSTRACT FROM AUTHOR]

In a globalised world, the transfer of carbon between regions, either physically or embodied in production, represents a substantial fraction of global carbon emissions. The resulting emission transfers are important for balancing regional carbon budgets and for understanding the drivers of regional emissions. In this paper we synthesise current understanding in two parts: (1) embodied CO2 emissions from the production of goods and services produced in one country but consumed in others, (2) physical carbon flows in fossil fuels, petroleum-derived products, harvested wood products, crops, and livestock. We describe the key differences between studies and provide a consistent set of estimates using the same definitions, modelling framework, and consistent data. We find the largest trade flows of carbon in international trade in 2004 were fossil fuels (2673MtC, 37% of global emissions), CO2 embodied in traded goods and services (1661MtC, 22% of global emissions), livestock (651MtC, 20% of total livestock carbon), crops (522MtC, 31% of total harvested crop carbon), petroleum-based products (183MtC, 50% of their total production), and harvested wood products (149MtC, 40% of total roundwood extraction). We find that for embodied CO2 emissions estimates from independent studies are robust. We found that differences between individual studies is not representative of the uncertainty in consumption-based estimates as different studies use different production-based emission estimates as input and different definitions of allocating emissions to international trade. After adjusting for these issues, results across independent studies converge to give less uncertainty than previously assumed. For physical carbon ?ows there are relatively few studies to be synthesised, but differences between existing studies are due to the method of allocating to international trade with some studies using "apparent consumption" as opposed to "final consumption" in more comprehensive approaches. While results across studies are robust to be used in further applications, more research is needed to understand the differences between methods and to harmonise definitions for particular applications. [ABSTRACT FROM AUTHOR]

Paper birch (Betula papyrifera Marsh) seedlings were grown in a greenhouse in either subsoil or topsoil in factorial combination with two fertilization and drought regimes to investigate how different soil environments and nutrient availability drive belowground partitioning between growth, secondary metabolism and ectomycorrhizal (EM) associations, and impact drought tolerance of paper birch. Root and total seedling dry biomass, starch, soluble sugars, soluble phenolics, lignin and EM abundance were quantified. In unfertilized topsoil, total plant biomass and root biomass were approximately nine times higher than in unfertilized subsoil, but the root weight ratios did not differ between soils. Root soluble phenolics and lignin were higher in unfertilized subsoil than in unfertilized topsoil, whereas EM abundance was significantly higher in unfertilized topsoil than in unfertilized subsoil. In topsoil, fertilization decreased root biomass and EM abundance and increased root phenolics and lignin. In contrast, fertilization of subsoil increased root biomass but decreased root phenolics and lignin, while EM abundance was unaffected. In both soil types, fertilization reduced root weight ratios. Across soil types, EM abundance was negatively correlated with root soluble sugars, root phenolics and lignin, but this was driven mainly by the responses in the topsoil treatment. Our results show that soil fertility mediates carbon tradeoffs among defense, growth and EM associations. [ABSTRACT FROM PUBLISHER]

To study the effects of elevated CO2 concentration ([CO2]) on relationships between nitrogen (N) nutrition and foliar gas exchange parameters, white birch (Betula papyrifera Marsh.) seedlings were exposed to one of five N-supply regimes (10, 80, 150, 220, 290 mg Nl-1) in either ambient [CO2] (360 µmol mol-1) or elevated [CO2] (720 µmol mol-1) in environment-controlled greenhouses. Foliar gas exchange and chlorophyll fluorescence were measured after 60 and 80 days of treatment. Photosynthesis showed a substantial down-regulation (up to 57%) in response to elevated [CO2] and the magnitude of the down-regulation generally decreased exponentially with increasing leaf N concentration. When measured at the growth [CO2], elevated [CO2] increased the overall rate of photosynthesis (Pn) and instantaneous water-use efficiency (IWUE) by up to 69 and 236%, respectively, but decreased transpiration (E) and stomatal conductance (gs) in all N treatments. However, the degree of stimulation of photosynthesis by elevated [CO2] decreased as photosynthetic down-regulation increased from 60 days to 80 days of treatment. Elevated [CO2] significantly increased total photosynthetic electron transport in all N treatments at 60 days of treatment, but the effect was insignificant after 80 days of treatment. Both Pn and IWUE generally increased with increasing leaf N concentration except at very high leaf N concentrations, where both Pn and IWUE declined. The relationships of Pn and IWUE with leaf N concentration were modeled with both a linear regression and a second-order polynomial function. Elevated [CO2] significantly and substantially increased the slope of the linear regression for IWUE, but had no significant effect on the slope for Pn. The optimal leaf N concentration for Pn and IWUE derived from the polynomial function did not differ between the CO2 treatments when leaf N was expressed on a leaf area basis. However, the mass-based optimal leaf N concentration for Pn was much lower in seedlings in elevated [CO2] than in ambient [CO2] (31.88 versus 37.00 mg g-1). Elevated [CO2] generally decreased mass-based leaf N concentration but had no significant effect on area-based leaf N concentration; however, maximum N concentration per unit leaf area was greater in elevated [CO2] than in ambient [CO2] (1.913 versus 1.547 g N m-2). [ABSTRACT FROM AUTHOR]

In order to reduce the production cost of the methane carbon dioxide reforming reaction, and improve its actual production efficiency, in this paper, the optimal working parameters of the methane carbon dioxide reforming reaction are studied. The influence of different factors on methane conversion is studied via a single-factor numerical simulation analysis and the response surface methodology. Firstly, a numerical model of the methane carbon dioxide reforming reaction is established using Ansys Chemkin Pro software to analyze the influence of single factors (reactor temperature, reaction pressure, gas velocity) on methane conversion rate; secondly, the response surface model with the methane conversion rate as the response value is established using the BBD (Box–Behnken design) method; and finally, the order of influence of each variable on methane conversion and the optimal reaction conditions are determined using the response surface method. The factors are listed in order of their influence on methane conversion as follows: reactor temperature > pressure > speed. The results show that when the temperature is 1135.114 K, the pressure is 0.103 MPa and the speed is 10slpm, the methane conversion rate is 93.7018%. In this paper, a method is adopted in which chemical reaction process simulation and numerical results prediction are combined, significantly reducing the simulation time and improving the calculation efficiency and accuracy, thus being of considerable scientific significance and theoretical value. [ABSTRACT FROM AUTHOR]

In the industrialization process, the difficulty in implementing environmental protection and enhancing the effect of environmental emission reduction are common problems to the developing countries, which are directly related to the quality of social development. This paper takes environmental centralization as the solution idea, takes the vertical management reform of environmental protection agencies implemented in China as the research object, and evaluates the environmental emission reduction effect and mechanism of action of centralized reform based on provincial environmental economic panel data using difference-in-differences model and intermediary model. The following conclusions are drawn: (1) The environmental centralization has significantly improved the provincial environmental emission reduction effect. After China's vertical management reforms were implemented, per capita CO2 emissions decreased by 11.1%, and industrial source SO2 emissions fell by 35.7%. (2) By increasing investment in urban environmental infrastructure construction, the reform has raised the level of investment and regulation in environmental protection construction, which in turn has effectively improved the ability to reduce environmental emissions. (3) After the implementation of the reform, the emission reduction effects of the reform on per capita CO2 and industrial source SO2 are 10.1% and 14.2% higher in provinces with lower industrial output value compared to those with higher industrial output value. At the same time, the effect of reform in provinces with a strong degree of local government intervention was significantly lower than that in provinces with a weak degree of local government intervention. The emission reduction effects of the reform implementation are 10.2% (per capita CO2) and 30.5% (industrial source SO2) lower, respectively. Based on the above findings, this paper argues that environmental centralization is an effective measure to advance the improvement of environmental quality and efficiency. In addition, China's reform experience has implications for other developing countries. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) emissions and haze pollution are often thought to have the same origin, the burning of fossil fuels. However, their relationship is not always synergistic and may even exhibit mutual constraints. Carbon-biased technological progress has emerged as a promising approach for simultaneously achieving three goals - to reduce CO2 emissions, alleviate the haze pressure, and keep economic growth. This study empirically investigates the impact and mechanisms of carbon-biased technological progress on carbon haze collaborative governance using data from 286 Chinese cities during 2006-2021. The results indicate that: (1) Carbon biased technological progress positively influences carbon haze collaborative governance. (2) This progress achieves coordination by enhancing element allocation efficiency, carbon efficiency, and responding to public environmental demands. (3) The facilitating role of carbon biased technological progress to carbon haze collaborative governance will work better if external conditions are met. Moreover, the effectiveness of carbon-biased technological progress in promoting coordination is contingent upon high levels of marketization, government intervention, environmental regulation, and technical advancements. Local and regional governments should foster conducive conditions for carbon dioxide and haze pollution coordination, optimize the allocation and flow of carbon resources, ensure harmonization between environmental regulation policies and other sectors, and bolster international cooperation and technical knowledge exchange to collectively address global environmental challenges., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

The reduction of carbon dioxide (CO 2 ) and nitrogen (N 2 ) to value-added products is a substantial area of research in the fields of sustainable chemistry and renewable energy that aims at reducing greenhouse gas emissions and the production of alternative fuels and chemicals. The current work deals with the synthesis of pyrochlore-type europium stannate (Eu 2 Sn 2 O 7 : EuSnO), tungsten disulfide (WS 2 :WS), and novel EuSnO/WS heterostructure by a simple and facile co-precipitation-aided hydrothermal method. Using different methods, the morphological and structural analyses of the prepared samples were characterized. It was confirmed that a heterostructure was formed between the cubic EuSnO and the layered WS. Synthesized materials were used for photocatalytic CO 2 and N 2 reduction under UV and visible light. The amount of CO and CH 4 evolved due to CO 2 reduction is high in EuSnO/WS (CO = 104, CH 4  = 64 μmol h -1 g -1 ) compared to pure EuSnO (CO = 36, CH 4  = 70 μmol h -1 g -1 ) and WS (CO = 22, CH 4  = 1.8 μmol h -1 g -1 ) under visible light. The same trend was observed even in the N 2 fixation reaction under visible light, and the amount of NH 4 + produced was found to be 13, 26, and 41 μmol h -1 g -1 in the presence of WS, EuSnO and EuSnO/WS, respectively. Enhanced light-driven activity towards CO 2 and N 2 reduction reactions in EuSnO/WS is due to the efficient charge separation through the formation of type-II heterostructure, which is in part associated with photocurrent response, photoluminescence, and electrochemical impedence spectroscopic (EIS) results. The EuSnO/WS heterostructure's exceptional stability and reusability may pique the attention of pyrochlore-based composite materials in photocatalytic energy and environmental applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Against the backdrop of global climate change and the "dual carbon" target, cities have a significant responsibility to achieve carbon reduction targets. As a crucial urban agglomeration in northern China, effectively balancing economic growth with CO 2 emission reduction to achieve high-quality economic development remains a significant challenge that the Beijing-Tianjin-Hebei region should address both presently and in the future. The objective of this study is to utilize nighttime lighting data and energy consumption information to quantify the CO 2 emissions of diverse cities within the Beijing-Tianjin-Hebei region spanning from 2006 to 2020. The research aims to analyze the spatial progression patterns of CO 2 emissions across these urban centers, identify key determinants and their interrelations, and delve into the underlying mechanisms pivotal for advancing carbon mitigation strategies within urban agglomerations. The results indicate that: with an exception in Beijing where CO 2 emissions slightly decreased compared to 2006, CO 2 emissions increased across cities in the Beijing-Tianjin-Hebei region by 2020. High-value CO 2 emission areas are primarily concentrated in central of the study area, exhibiting negative spatial correlation characteristics. Based on its urban development positioning, it is imperative for the Beijing-Tianjin-Hebei urban agglomeration to formulate and implement carbon reduction strategies on innovative development, industrial upgrading, and ecological protection among other aspects towards coordinated low-carbon development., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study investigates the influence of foreign direct investment (FDI), financial development (FD), and governance on carbon emissions in 15 emerging Asian economies (EAEs) from 2000 to 2021. It aims to assess how successful these nations have been in upholding ecological sustainability while promoting themselves as alternative manufacturing destinations to China and fostering domestic manufacturing through significant financial development. It creates a composite governance quality (GQ) measure and three subdimensions-EcoGov, InstGov, and PolGov-to assess its precise role in influencing the FDI-carbon dioxide (CO 2 ) and FD-CO 2 nexuses. Using fully modified ordinary least squares (FMOLS) and dynamic ordinary least squares (DOLS) panel cointegration techniques, this study yielded findings revealing that FDI and FD significantly enhance carbon emissions. The overall GQ significantly moderates the FD-CO 2 nexus but fails to moderate FDI's detrimental environmental influence. More specifically, EcoGov significantly moderates FDI's and FD's influence on carbon emissions, whereas InstGov significantly enhances their influence on emissions. In contrast, PolGov is only found to moderate FD's impact on environmental quality since the Government frequently endorses liberal environmental regulations to facilitate FDI-led growth. The findings from this study are robust and carry distinct policy ramifications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Accumulations of macroalgal wrack are important for adequate functioning of the beach ecosystem. However, the sudden beaching of seaweed masses smothers the coastline and forms decomposing piles on the shore, harming tourism-based economies, but also affecting the beach ecosystem metabolism. The decomposition of sudden pulses of wrack can modify the biogeochemistry of beach sands and increase greenhouse gas (GHG) emissions. The presence of invasive species in the wrack deposits can superimpose harmful effects on the beach functioning. We quantified the wrack biomass of Rugulopteryx okamurae, an invasive species of extreme impact, on five sandy beaches from the Atlantic coast of the Strait of Gibraltar (Spain), and we tested the effects on in situ respiratory CO 2 fluxes using an infrared gas analyser. All the beaches showed massive accumulations of Rugulopteryx wrack deposits. However, the biomass changed significantly between beaches, ranging (mean ± SE) from 968.3 ± 287.7 kg m -1 to 9210 ± 1279.4 kg m -1 of wet weight. Wrack supported high respiration rates, with CO 2 fluxes averaging (±SE) 19.15 ± 5.5 μmol CO 2 m -2 s -1 across beaches, reaching astounding maximum peaks of 291 μmol CO 2 m -2  s -1 . The within-beach variability was related to the distance of the wrack deposits from the shoreline, as the average metabolic rates tended to increase significantly from the swash to the drift line. Thicker wrack and a more degraded algae stage showed significantly higher CO 2 fluxes. We estimated that the annual CO 2 flux of R. okamurae in our study area ranged between 0.39 (±0.01) and 23.30 (±11.33) kg C m -2 y -1 . We suggest that massive amounts of beach wrack can become a globally significant contributor to GHG emissions that can offset any potential carbon-sink capacity of macroalgal forests. However, the piles of wrack located several meters above the drift line showed non-measurable CO 2 efflux. Transferring beach wrack from swash to drier upper-beach areas, a common practice in many coastal regions suffering from massive wrack accumulations, might help reduce GHG emissions while removing the wrack stockpiles from the intertidal. However, this practice is not necessarily suitable for all beaches and can create ecological and conservation problems in the dune system. There is an urgent need to implement practical and sustainable management practices for massive wrack deposits capable of presenting various solutions to achieve a balance between conservation and recreation actions, answering the consequences of a problem that links both, environmental and economic issues., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: IFR reports financial support was provided by Government of Andalusia. IFR reports financial support was provided by Spain Ministry of Science and Innovation. IFR reports financial support was provided by European Social Fund. IG reports financial support was provided by Government of Spain Ministry of Universities. ABI reports was provided by European Maritime and Fisheries Fund. IFR reports equipment, drugs, or supplies was provided by European Regional Development Fund. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Growing concerns about the level of CO 2 emissions have made identifying the key drivers of the emission issue a critical agenda item. These developments have turned identifying drivers of CO 2 emissions into a popular research area. Researchers have been attempting to determine the root causes of CO 2 emissions for quite some time. While many economic factors have been associated with the emission levels, researchers' interest in undiscovered factors has brought political factors to the forefront. Although some institutional/political factors have been linked to CO 2 emissions in the relevant literature, the specific impact of freedom of expression and belief (FEB) has yet to be examined. Notably, as democracies' provision of economic freedoms motivates production and consumption, exerting pressure on the environment, FEB can balance it. This study is a pioneering attempt to seek answers to this question. By assigning a specific role to FEB, the research seeks to determine the key factors influencing CO 2 emissions in the Group of Seven (G7) between 2006 and 2022. Results suggest that FEB might be crucial in lowering CO 2 emissions, whereas economic expansion and energy use tend to increase CO 2 emissions. However, the impact of trade openness has yet to be found to be significant. Thus, securing and enhancing FEB could lead to significant environmental gains in G7 countries and globally., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Heatwaves, expected to become more frequent, pose a significant threat to plant biomass production. This experiment was designed to estimate heatwave influence on Brassica juncea phytoremediation when superimposed on different CO 2 levels. A 7-day heatwave was generated during the species flowering stage. Heatwaves decreased all B. juncea dry weights. The lowest species dry weight was recorded when the heatwave was accompanied by 250 ppm CO 2 , in which the biomass significantly decreased by 40.0% relative to that of no heatwave under the same atmospheric CO 2 conditions. Heatwave superposition with 250 ppm CO 2 reduced the Cd content in B. juncea aerial parts by 28.1% relative to that of identical environmental conditions without heatwave, whereas the opposite result was observed under 550 ppm CO 2 conditions. The heatwave caused oxidative damage to B. juncea under all CO 2 conditions, as manifested by increased malondialdehyde levels in the plant shoots. With heatwave superposition, antioxidant enzyme activity was enhanced by exposure to 400 and 550 ppm CO 2 . Considering biomass yield generation and Cd uptake capacity, heatwave superposition decreased the B. juncea phytoremediation effects, and high atmospheric CO 2 conditions could alleviate detrimental effects to a certain extent. This study uniquely examines the combined effects of heatwaves and varying CO 2 levels on phytoremediation, providing microscopic insights into oxidative damage and enzyme activity, highlighting the potential for CO 2 enrichment to mitigate heatwave impacts, and offering comprehensive analysis for future agricultural practices and environmental management., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Thermosetting polymers are used in a wide range of applications due to their robust mechanical strength and superior flame retardancy. Despite these technical benefits, recycling of thermosetting polymers has been challenging because of their crosslinking nature. Moreover, their disposal through conventional methods (landfill and combustion) poses environmental concerns, such as microplastics and air pollutants. To address these issues, this study introduces a thermo-chemical disposal platform for thermosetting polymer wastes that employs carbon dioxide (CO 2 ) as a reactive medium. In this work, melamine-formaldehyde was used as model compound of thermosetting polymers. In single-stage pyrolysis, it was revealed that CO 2 plays a crucial role in controlling in the compositional matrices of pyrolytic gases, liquid products, and wax. These compositional changes were attributed to the homogeneous reactions between CO 2 and the volatile compounds released from the thermolysis of MF. To enhance the thermal cracking of the MF, a double-stage pyrolysis process was tested, which increased the production of pyrolytic gases and eliminated wax formation. However, the slow kinetics governing the reactivity of CO 2 limits the occurrence of homogeneous reactions. A nickel-based catalyst was used to accelerate reaction kinetics. The catalytic pyrolysis under CO 2 conditions led to substantial increases in syngas (H 2 and CO) production of 880% and 460%, respectively, compared with double-stage pyrolysis. These findings demonstrate that thermosetting polymer wastes can be valorized into gaseous fuels through thermo-chemical process, and CO 2 enhances the recovery of energy and chemicals. Therefore, this study presents an innovative technical platform to convert thermosetting polymer wastes and CO 2 into syngas., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The conversion of carbon dioxide (CO 2 ) to methane (CH 4 ) is a strategy for sequestering CO 2 . Zero-valent iron (ZVI) has been proposed as an alternative electron donor for the CO 2 reduction to CH 4 . In this study, the effects of ZVI concentrations on the abiotic production of H 2 (without the action of microorganisms) in the first part and on the biological conversion of CO 2 to CH 4 using ZVI as a direct electron donor in the second part were examined. In the abiotic H 2 production, the increase in the ZVI concentration from 16 to 32, 64, and 96 g/L was found to have positive effects on both the amounts of H 2 generated and the rates of H 2 production because the extent of ZVI oxidation positively correlates with increasing surface area. Nevertheless, the increase in ZVI concentration from 96 to 224 g/L did not benefit the H 2 production because the ZVI dissolution was suppressed by the increasing aqueous pH above 10. In the bioconversion of CO 2 to CH 4 using ZVI as an electron donor, the main methanogenesis pathway occurred via hydrogenotrophic methanogenesis at pH 8.7-9.5 driven by the genus Methanobacterium of the class Methanobacteria. At ZVI concentrations of 64 g/L and above, the production of volatile fatty acid (VFA) became clear. Acetate was the main VFA, indicating the induction of homoacetogenesis at ZVI concentrations of 64 g/L and above. In addition, the presence of propionate as the second major VFA suggests the production of propionate from CO 2 and acetate under conditions with high H 2 partial pressure. The results indicated that the pathway for ZVI/CO 2 conversion to CH 4 was competitive between hydrogenotrophic methanogenesis and homoacetogenesis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Solar geoengineering (SG) solutions have many advantages compared to the difficulty of carbon dioxide removal (CDR): SG produces fast results, is shown here to have much higher efficiency than CDR, is not related to fossil fuel legislation, reduces the GHG effect including water vapor, and is something we all can participate in by brightening the Earth with cool roofs and roads. SG requirements detailed previously to mitigate global warming (GW) have been concerning primarily because of overwhelming goals and climate circulation issues. In this paper, annual solar geoengineering (ASG) equations and estimated requirements for yearly solar radiation modification (SRM) of areas are provided along with the advantages of annual solar geoengineering (ASG) to mitigate yearly global warming temperature increases. The ASG albedo area modification requirements found here are generally 50 to potentially more than 150 times less compared to the challenge of full SG GW albedo mitigation, reducing circulation concerns and increasing feasibility. These reductions are applied to L1 space sunshading, Earth brightening, and stratosphere aerosol injection (SAI) SRM annual area requirements. However, SAI coverage compared to other methods will have higher yearly increasing maintenance costs in the annual approach. Results also show that because ASG Earth albedo brightening area requirements are much smaller than those needed for full mitigation, there are concerns that worldwide negative SG would interfere with making positive advances for several reasons. That is, negative SG currently dominates yearly practices with the application of dark asphalt roads, roofs, and building sides. This issue is discussed. [ABSTRACT FROM AUTHOR]

In response to the urgent need to address climate change and reduce carbon emissions, there has been a growing interest in innovative approaches that integrate AI and CDR technology. This article provides a comprehensive review of the current state of research in this field and aims to highlight its potential implications with a clear focus on the integration of AI and CDR. Specifically, this paper outlines four main approaches for integrating AI and CDR: accurate carbon emissions assessment, optimized energy system configuration, real-time monitoring and scheduling of CDR facilities, and mutual benefits with mechanisms. By leveraging AI, researchers can demonstrate the positive impact of AI and CDR integration on the environment, economy, and energy efficiency. This paper also offers insights into future research directions and areas of focus to improve efficiency, reduce environmental impact, and enhance economic viability in the integration of AI and CDR technology. It suggests improving modeling and optimization techniques, enhancing data collection and integration capabilities, enabling robust decision-making and risk assessment, fostering interdisciplinary collaboration for appropriate policy and governance frameworks, and identifying promising opportunities for energy system optimization. Additionally, this paper explores further advancements in this field and discusses how they can pave the way for practical applications of AI and CDR technology in real-world scenarios. [ABSTRACT FROM AUTHOR]

Christian environmental ethics have always navigated the thin line between the Scylla of pantheism and the Charybdis of deism. On the one hand, removing God from the world avoids pantheism but can inadvertently render the divine a distant, absentee father who cares little about what we do with the environment. On the other hand, if we bring the Creator too close to creation, we may begin to blur the distinction between them, fringing on pantheism. While making nature divine might at first seem to heighten the environmental desecration of the earth by making it a literal de-sacralizing of the sacred, this may be only a surface-level reading (or, at least, only true of very carefully nuanced versions of pantheism). For the pantheist, God would not just be the trees but the machines that log them; God would not just be the polar bears but the carbon dioxide that is evicting them. God would be no more present in that which is desecrated than in that which does the desecration (e.g., God would be one with the pesticides, bulldozers, and factory smoke). By making God everything, it becomes difficult to call any person, act, legislation, or event godless. This paper offers Henry More's view of divine space as a constructive, Platonic Christian middle way between these two extremes, charting a God who is spatially present to nature without being pantheistically reducible to it, in the same way that space is intimately close to the objects within it while nonetheless remaining distinct from them. The bulk of the paper counters potential opponents to this proposal, specifically defending Morean space from the charge that it would break down the Creator–creature distinction and/or cave to the environmental Scylla of pantheism. [ABSTRACT FROM AUTHOR]

The extensive utilization of fossil fuels has led to a rapid increase in atmospheric CO2 concentration, resulting in various environmental issues. To reduce reliance on fossil fuels and mitigate CO2 emissions, it is important to explore alternative methods of utilizing CO2 and H2 as raw materials to obtain high-value-added chemicals or fuels. One such method is CO2 methanation, which converts CO2 and H2 into methane (CH4), a valuable fuel and raw material for other chemicals. However, CO2 methanation faces challenges in terms of kinetics and thermodynamics. The reaction rate, CO2 conversion, and CH4 yield need to be improved to make the process more efficient. To overcome these challenges, the development of suitable catalysts is essential. Non-noble metal catalysts have gained significant attention due to their high catalytic activity and relatively low cost. In this paper, the thermodynamics and kinetics of the CO2 methanation reaction are discussed. The focus is primarily on reviewing Ni-based, Co-based, and other commonly used catalysts such as Fe-based. The effects of catalyst supports, preparation methods, and promoters on the catalytic performance of the methanation reaction are highlighted. Additionally, the paper summarizes the impact of reaction conditions such as temperature, pressure, space velocity, and H2/CO2 ratio on the catalyst performance. The mechanism of CO2 methanation is also summarized to provide a comprehensive understanding of the process. The objective of this paper is to deepen the understanding of non-noble metal catalysts in CO2 methanation reactions and provide insights for improving catalyst performance. By addressing the limitations of CO2 methanation and exploring the factors influencing catalyst effectiveness, researchers can develop more efficient and cost-effective catalysts for this reaction. [ABSTRACT FROM AUTHOR]

Using an aerosol–climate coupled model, this paper has investigated the changes in distributions of anthropogenic and natural particles due to 4 × CO2-induced global warming, under the low emission scenario of Representative Concentration Pathway 4.5 (RCP4.5). Special attention is paid to the seasonal variations of aerosol size modes. With rising CO2 levels, surface warming, and changes in atmospheric circulations and hydrologic cycles are found during both summer (JJA) and winter (DJF). For anthropogenic particles, changes in fine anthropogenic particulate matter (PM2.5, particles with diameters smaller than 2.5 μm) decrease over high-latitude regions and increase over the tropics in both DJF and JJA. Global mean column concentrations of PM2.5 decrease by approximately 0.19 mg m−2, and concentrations of coarse anthropogenic particles (CPM, particles with diameters larger than 2.5 μm) increase by 0.005 mg m−2 in JJA. Changes in anthropogenic particles in DJF are similar to those in JJA, but the magnitudes of maximum regional changes are much smaller than those in JJA. The coarse anthropogenic particles (CPM, particles with diameters larger than 2.5 μm) increase over northern Africa and the Arabian Peninsula during JJA, whereas changes in anthropogenic CPM during DJF are minimal. During both JJA and DJF, changes in anthropogenic CPM are about two orders of magnitude smaller than those of anthropogenic PM2.5. Enhanced wet deposition by large-scale precipitation under rising CO2-induced surface warming is the critical factor affecting changes in anthropogenic particles. For natural particles, the distribution of change in the natural PM2.5 burden is similar to that of natural CPM, but much larger than natural CPM during each season. Both natural PM2.5 and CPM burdens increase over northern Africa and the Arabian Peninsula during JJA, but decrease over most of the continental regions during DJF. Changes in surface wind speed, divergence/convergence of surface wind, and precipitation are primary reasons for the variation of natural particles. [ABSTRACT FROM AUTHOR]

The accumulation of carbon dioxide in the atmosphere due to fossil fuel burning and deforestation has caused global warming and an increase in extreme weather events. To complement the shift towards clean energy, it is crucial to adopt methods for carbon dioxide removal, known as negative emission technologies. Enhanced weathering is one such approach that involves accelerating the natural process of rock weathering by spreading finely ground rocks over large areas, such as agricultural land or coastal areas. This exploratory review paper provides an overview of the fundamental mechanisms behind enhanced weathering, and outlines the techniques for its implementation. The environmental benefits of enhanced weathering are highlighted, including carbon dioxide removal, and improvement of soil fertility. Furthermore, potential impacts on ecosystems and biodiversity are examined, along with the effects on water, soil and air quality. The paper also considers the risks and challenges associated with large-scale implementation and long-term stability of enhanced weathering. Additionally, the integration of enhanced weathering with Sustainable Development Goals is explored, along with the potential co-benefits and trade-offs with other sustainability objectives. To conclude, this exploratory review paper summarizes the key findings and proposes avenues for further research in this field of enhanced weathering. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) capture and separation constitute an important field of research as we seek to reduce the effects of climate change. Because of their porosity, resilient crystallinity, high adsorption capacity, and affinity for CO2, cyclodextrin-based metal-organic frameworks (CD-MOFs) have emerged as attractive materials for carbon capture. This paper gives an overview of CD-MOFs and their applications in CO2 capture and separation. Several studies have been conducted to synthesize and characterize CD-MOFs for CO2 capture. The causes of the high binding affinity of CO2 in CD-MOFs were discovered through mechanistic studies on CO2 adsorption. Furthermore, CD-MOF modifications have been carried out to improve the sorption capacity and selectivity of CO2 adsorption. Meanwhile, several researchers have reported using CD-MOFs for gaseous CO2 membrane separation. This paper also highlights the current gaps in CD-MOF research and future outlooks in carbon capture and separation using CD-MOFs. [ABSTRACT FROM AUTHOR]

The interaction between CO2, formation water, and rock surfaces after CO2 flooding and the mechanism by which it affects CO2 storage were studied in this paper. The results show that variations in the solubility of CO2 in crude oil under pressure are similar to those observed in formation water. The solubility of CO2 increases as pressure increases under a low-pressure conditions. The solubility of CO2 in crude oil increases significantly when crude oil is in a low-viscosity state, and this makes it easier to diffuse CO2 into the oil phase at high temperatures. More resistance is encountered when CO2 diffuses into the liquid-containing space of an irregular core, making the coefficient of diffusion into the oil–water two-phase flow in the porous medium smaller. After the core is corroded by a CO2-saturated aqueous solution, the quartz content in the mineral component increases and the plagioclase and potassium feldspar content significantly decrease. The dissolution of the feldspar leads to the formation of a large amount of secondary kaolinite, thus increasing the kaolinite content. In the early stage of CO2 erosion during dynamic displacement, the combined effect of particle migration and inorganic precipitation leads to a slow growth in core permeability and porosity. As the erosion progresses, the influence of particle migration and inorganic precipitation on permeability gradually decreases, while the porosity of the core gradually increases. The secondary pores play a role, and the erosion of the CO2–water system makes the permeability and porosity of the core gradually increase. During dynamic displacement, CO2 is mainly stored in the reservoir in free and irreducible states. Under the pressure of the reservoir, some of the CO2 participates in erosion reactions and is stored in the rock or the solution in the form of minerals or ions. In addition, a small portion of the CO2 is dissolved in the residual water and residual oil that remain after the dynamic displacement. The results of this paper can provide some theoretical support for the design of a CO2 storage site. [ABSTRACT FROM AUTHOR]