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Effectively tackling extreme climate change requires sound knowledge about carbon emissions and their driving forces. Currently, agricultural carbon emission assessment often deals with its inventory, efficiency, determinants, and response independently, which will leave out the complex interactions among its various components, thus there is a lack of comprehensive, scalable, comparable explanations for agricultural carbon emissions. Herein, we introduce an integrated agricultural carbon emission assessment framework (IEDR): Inventory (I) × Efficiency (E) × Determinants (D) × Response (R), which was then applied to an illustration for the county-level agricultural carbon emissions in Hunan Province, China. Results show that: (1) Agricultural carbon emission inventory (ACEI) increased from 20.06 × 10 6 tC in 2006 to 21.99 × 10 6 tC in 2014 and decreased to 19.07 × 10 6 tC by 2020, depicting a fluctuating trend. Meanwhile, there was remarkable spatial heterogeneity, with higher ACEI in the North and South than in the East and West. (2) Agricultural carbon emission efficiency (ACEE) increased from 0.8520 in 2006 to 0.8992 in 2020, depicting a growing trend driven by technological progress. Spatially distributed in contrast to ACEI, regions with higher ACEE were located in the eastern and western areas. (3) ACEI was negatively correlated with ACEE (-0.657), indicating that increasing ACEE is a key strategy for reducing emissions. (4) The natural environment, rural development level, and policy support had critical impacts on ACEE and ACEI. In particular, the cultivated area and rural water affairs development were significant influences on ACEE and ACEI. Given the externalities of carbon emissions and its important public goods characteristics of the atmosphere, local carbon issues are also global concerns. Therefore, the case study of the IEDR model not only validates this theoretical paradigm and realizes regional responsibility for global carbon reduction but also supports and expands the theoretical and empirical corpus in the field of agricultural carbon emissions and efficiency, providing insights and references for other global regions facing similar 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 Elsevier Ltd. All rights reserved.)

Accelerating the attainment of carbon balance in Chinese cities has become pivotal in addressing global climate change and promoting green, low-carbon development. This study, encompassing 277 prefecture-level and above cities from 2007 to 2020, reveals a positive overall trend in China's urban carbon balance index. The evolution unfolds in two stages, demonstrating a distinct "tiered development" pattern across the eastern, central and western regions. Moreover, significant spatial agglomeration characteristics characterize China's carbon balance hot and cold spots throughout the study period, with their spatial agglomeration degree remaining stable. The standard deviation ellipse analysis confirms these hot and cold spots' alignment with China's economic development level and population distribution. The GTWR test results highlight the pronounced non-stationary characteristics of different driving factors in space and time, exhibiting variations in strength and direction among regions. Consequently, enhancing China's urban carbon balance requires tailored measures based on different areas' unique conditions and development characteristics, emphasizing a hierarchical and classified approach to leverage distinct driving factors and foster a green development system in China., 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.)

In the context of global climate change threatening human survival, and in a post-pandemic era that advocates for a global green and low-carbon economic recovery, conducting an in-depth analysis to assess whether green finance can effectively support low-carbon economic development from a dynamic perspective is crucial. Unlike existing research, which focuses solely on the average effects of green credit (GC) on carbon productivity (CP), we introduce a non-parametric panel data model to investigate GC's impact on CP across 30 provinces in China from 2003 to 2021, verifying a significant time-varying effect. Specifically, during the first phase (2003-2008), GC negatively impacted CP. In the second phase (2009-2014), this negative influence gradually diminished and transformed into a positive effect. In the third phase (2015-2021), GC continued to positively influence CP, although this effect became insignificant during the pandemic. Further subgroup analysis reveals that in the regions with low environmental regulations, GC did not significantly boost CP throughout the sample period. In contrast, in the regions with high environmental regulations, GC's positive effect persisted in the mid to late stages of the sample period. Additionally, compared to the regions with low levels of marketization, the impact of GC on CP was more pronounced in highly marketized regions. This indicates that the promoting effect of GC on CP depends on strong support from environmental regulations and well-functioning market mechanisms. By adopting a non-parametric approach, this study reveals variations in the impact of GC on CP across different stages and under the influence of the pandemic shock, offering new insights into the relationship between GC and China's CP., 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.)

China's commitment to attaining carbon neutrality by 2060 has galvanized research into carbon sequestration, a critical approach for mitigating climate change. Despite the rapid urbanization observed since the turn of the millennium, a comprehensive analysis of how urbanization influences urban carbon storage throughout China remains elusive. Our investigation delves into the nuanced effects of urbanization on carbon storage, dissecting both the direct and indirect influences by considering urban-suburban gradients and varying degrees of urban intensity. We particularly scrutinize the roles of climatic and anthropogenic factors in mediating the indirect effects of urbanization on carbon storage. Our findings reveal that urbanization in China has precipitated a direct reduction in carbon storage by approximately 13.89 Tg of carbon (Tg C). Remarkably, urban sprawl has led to a diminution of vegetation carbon storage by 8.65 Tg C and a decrease in soil carbon storage by 5.24 Tg C, the latter resulting from the sequestration of impervious surfaces and the elimination of organic matter inputs following vegetation removal. Meanwhile, carbon storage in urban greenspaces has exhibited an increase of 6.90 Tg C and offsetting 49.70% of the carbon loss induced by direct urbanization effects. However, the indirect effects of urbanization predominantly diminish carbon storage in urban greenspaces by an average of 5.40%. The degree of urban vegetation management emerges as a pivotal factor influencing the indirect effects of urbanization on carbon storage. To bolster urban carbon storage, curbing urban sprawl and augmenting urban green spaces are imperative strategies. Insights from this study are instrumental in steering sustainable urban planning and advancing towards the goal of carbon neutrality., 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 impact of China's Low-Carbon Pilot Policy on analyst forecast behaviors. Using a staggered difference-in-difference approach, we find that the program reduced analyst forecast errors and divergence, as mandatory sustainability disclosures enable analysts to incorporate new information to improve forecast quality. The effect is concentrated in state-owned firms and manufacturing-oriented cities. Additional tests explore accounting information quality and investor attention as plausible channels. Overall, exploiting a major Chinese environmental regulation, we provide novel evidence that green policies can enhance transparency and capital market efficiency. The findings offer implications for regulators, investors, and managers as countries pursue climate change mitigation strategies., 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.)

Cities generate substantial carbon emissions while facing serious climate challenges. The construction of low-carbon cities is a vital measure to cope with climate change. China has implemented three batches of low-carbon city pilots since 2010, with advocating low-carbon lifestyles and consumption patterns for residents as an indispensable component. However, there is limited research on the impact of pilot cities on carbon emissions of residents, as well as a lack of theoretical guidance and accurate data. Based on 281 prefectural-level cities in China, this study established the difference-in-differences model to evaluate the impact of low-carbon city pilots on residents' carbon emissions. By introducing the Attitudes, Behaviours, and Circumstances theory as the analytical framework and compiling a direct carbon emission inventory of residents, this study attempts to fill the research gap. The results indicate that low-carbon city pilots could lower residents' carbon emissions by 7.3% annually, with a gradual strengthening trend over time. This study presents and validates three influencing mechanisms of the pilot policy, including improving green attitudes, advocating low-carbon behaviours, and optimizing living circumstances. The heterogeneity analysis demonstrates that the eastern and central regions with higher levels of economic development have generated significant policy effects. Although both the northern and southern pilot cities have lowered residents' carbon emissions, the former has exhibited a stronger policy effect. Based on these findings, this study proposes several policy recommendations: innovate attitudinal guidance, nudge behavioural choices, shape external circumstances, and combine local characteristics., 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 © 2023 Elsevier Ltd. All rights reserved.)

In an era marked by escalating climate change, the fragile ecological balance faces increasing strain. Whilst significant knowledge exists regarding the accumulation of carbon emission within the Association of Southeast Asian Nations, little is known about when and how countries could reach net-zero emission goal as agreed in Paris Agreement. For this purpose, our study examines the primary driving factors of carbon emission from 1990 to 2020 across the ten countries using the Logarithmic Mean Divisia Index model. We leverage the random forest model to explore the net-zero scenarios and the Autoregressive Integrated Moving Average approach to identify the evolutionary trajectories of carbon emission trends. Our findings underscore the imperative need for expediting decarbonization efforts, emphasizing the urgency for widespread adoption of clean technologies and substantial investment in green initiatives. Countries at similar stages of progress might establish a cooperation mechanism of clean energy base construction, energy storage allocation and policy formulation. These insights can help us better estimate future demand of clean energy, explore strategies for decarbonization, and inform historical commonalities of carbon emission growth., 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.)

Achieving the net zero emissions target that was set in the Paris Agreement to mitigate the risks of climate change seems increasingly difficult as countries and sectors of the economy are falling behind the expected trajectory. The building and construction industry, as one of the main contributors to global emissions, has an essential role to play toward this aim. Net zero emissions target has been introduced to this sector as well; however, achieving it is a very challenging and complex task. Many studies have been undertaken on implementing different measures and strategies to reduce the industry's carbon footprint. These studies identified many challenges and barriers in transforming the industry. This paper aims to provide a systematic review of challenges that organisations face in delivering new net zero emissions buildings. The relevant journal articles published since the Paris Agreement were identified and analysed using mixed-method data analysis, including quantitative (science mapping) and qualitative (thematic) analysis. The result showed increased attention to the subject over this period, with China, the UK, and Australia being the top contexts for research. The most discussed groups of barriers were "economic", "knowledge", and "technical", respectively, followed by "organisational", "market", "technological", and "legal" barriers. [ABSTRACT FROM AUTHOR]

The ocean's organic carbon export is a key control on atmospheric pCO2 and stimulating this export could potentially mitigate climate change. We use a data‐constrained model to calculate the sensitivity of atmospheric pCO2 to local changes in export using an adjoint approach. A perpetual enhancement of the biological pump's export by 0.1 PgC/yr could achieve a roughly 1% reduction in pCO2 at average sensitivity. The sensitivity varies roughly 5‐fold across different ocean regions and is proportional to the difference between the mean sequestration time τseq of regenerated carbon and the response time τpre of performed carbon, which is the reduction in the preformed carbon inventory per unit increase in local export production. Air‐sea CO2 disequilibrium modulates the geographic pattern of τpre, causing particularly high sensitivities (2–3 times the global mean) in the Antarctic Divergence region of the Southern Ocean. Plain Language Summary: Atmospheric CO2 levels could be reduced by stimulating plankton in the ocean to produce more organic carbon that then sinks to depth (is exported) at a higher rate. The resulting carbon deficit in surface waters drives atmospheric carbon into the ocean. The efficacy of this process depends on how long the exported carbon stays isolated from the surface and how quickly the surface deficit can be filled. Here we investigate how sensitive atmospheric CO2 levels are to a given enhancement in carbon export and where such enhancements would be most effective. We show that the sensitivity is determined by the difference between the time for which exported carbon stays sequestered at depth and the time with which the rest of the carbon in the ocean responds to the additional export rate. High sequestration times are found where the organic carbon is exported into old deep waters, while fast response times are found where it is easy for gas exchange to inject carbon into the ocean and where the additionally exported carbon is less likely to resurface and escape into the atmosphere. These factors result in the Southern Ocean and the tropics having greatest sensitivity. Key Points: pCO2 sensitivity to carbon export perturbations is governed by sequestration time, preformed response time, and atmospheric turnover timeHigh sensitivity occurs in the tropics and Southern Ocean where sequestration time is long and preformed response time is shortThe preformed response time is modulated by air‐sea CO2 disequilibrium and shortest in the Atlantic and Southern Ocean [ABSTRACT FROM AUTHOR]

The ocean is responsible for taking up approximately 25% of anthropogenic CO2 emissions and stores >50 times more carbon than the atmosphere. Biological processes in the ocean play a key role, maintaining atmospheric CO2 levels approximately 200 ppm lower than they would otherwise be. The ocean's ability to take up and store CO2 is sensitive to climate change, however the key biological processes that contribute to ocean carbon storage are uncertain, as are how those processes will respond to, and feedback on, climate change. As a result, biogeochemical models vary widely in their representation of relevant processes, driving large uncertainties in the projections of future ocean carbon storage. This review identifies key biological processes that affect how ocean carbon storage may change in the future in three thematic areas: biological contributions to alkalinity, net primary production, and interior respiration. We undertook a review of the existing literature to identify processes with high importance in influencing the future biologically‐mediated storage of carbon in the ocean, and prioritized processes on the basis of both an expert assessment and a community survey. Highly ranked processes in both the expert assessment and survey were: for alkalinity—high level understanding of calcium carbonate production; for primary production—resource limitation of growth, zooplankton processes and phytoplankton loss processes; for respiration—microbial solubilization, particle characteristics and particle type. The analysis presented here is designed to support future field or laboratory experiments targeting new process understanding, and modeling efforts aimed at undertaking biogeochemical model development. Plain Language Summary: The storage of carbon in the ocean forms an essential component of the Earth's carbon cycle. The contribution of ocean biology to carbon storage is not well constrained by observations and as a result has large uncertainties in the future model projections. There are a multitude of processes involved in the uptake, remineralization and storage of carbon, many of which have high uncertainty. Here we assess significant processes in determining net primary production, the biological contribution to alkalinity, and interior respiration. Using an extensive literature review, expert assessment and community survey, we rank processes as having high, moderate or low importance to the future biologically‐mediated storage of carbon in the ocean. This analysis is intended to support future observational studies and biogeochemical model development. Key Points: Key processes needed to improve projections of the response of ocean carbon storage to climate change identifiedThree themes are addressed: net primary production, interior respiration, and biological contributions to alkalinityAn expert assessment and community survey used to rank processes according to importance and uncertainty levels [ABSTRACT FROM AUTHOR]

The Mediterranean Basin is severely impacted by anthropogenic changes affecting both natural ecosystems and human livelihoods. The region is highly vulnerable to natural hazards, with floods being considered the most important, due both to their frequency and impacts. Koiliaris watershed (northwest of Crete Island, Greece) represents a relevant case study as past land-use changes via deforestation and intense cultivation practices induce soil organic matter losses, making soils susceptible to water erosion and desertification. The restoration of native riparian forests has been identified as the most effective nature-based solution (NBS) for the area. Through modeling, our study assessed the effectiveness of this NBS in addressing flood risk and erosion while providing additional ecosystem services (carbon sequestration and biodiversity conservation). A cost–benefit analysis has been then implemented to also investigate the sustainability of the investment from an economic point of view. Our results show the NBS would be successful in ensuring a better flow of targeted ecosystem services compared to the business-as-usual conditions. The associated investment would result in economic sustainability and associated costs would be paid back in five years. Though site-specific, our study provides lessons learned for dealing with future land-restoration challenges in the Mediterranean to cope with climate change-related challenges. [ABSTRACT FROM AUTHOR]

Carbon (C) in gaseous form is a component of several greenhouse gases emitted during the combustion of fossil fuels. C movement between the atmosphere, land (biosphere and lithosphere), and ocean (hydrosphere) alters the total amount in each pool. Human activities accelerate C movement into the atmosphere, causing increases in temperature. This shift from terrestrial and oceanic C pools to the atmosphere causes an increase in the intensity, frequency, and duration of catastrophic climate disturbances. Although society hears and reads about C emissions, there is a lack of understanding of its importance and the need to decrease it in the atmospheric pool to avoid exacerbating climate change. Forests and biochar are two biological methods to retain C in the terrestrial pool for a long time and at a very low cost. However, forest harvesting, the use of woody biomass as a source of renewable C for different applications, and the relationship with decreasing C emissions have created a highly controversial topic among governments, the scientific community, society in general, and social groups. The main objective of this review is to highlight the importance of C, forests, and biochar, including the benefits of C sequestration to decrease the impacts of climate change and promote sustainable forests and healthy soils in the future. The main findings show strong evidence that climate-smart forest management practices are an efficient option for managing C and increasing C stocks. This review suggests that forest management mitigation actions are another efficient C management approach with high potential. The findings show that biochar is a climate-smart tool that contributes to climate change mitigation by increasing soil carbon sequestration and reducing soil GHG emissions, including other associated benefits. [ABSTRACT FROM AUTHOR]

Each year, the biological carbon pump (BCP) transports large quantities of carbon from the ocean surface to the interior. The efficiency of this transfer varies geographically, and is a key determinant of the atmosphere‐ocean carbon dioxide balance. Traditionally, the attention has been focused on explaining perceived geographical variations in this transfer efficiency (TE) in an attempt to understand it, an approach that has led to conflicting results. Here we combine observations and modeling to show that the spatial variability in TE can instead be explained by the seasonal variability in carbon flux attenuation. We also show that seasonality can explain the contrast between known global estimates of TE, due to differences in the date and duration of sampling. Our results suggest caution in the mechanistic interpretation of annual‐mean patterns in TE and demonstrates that seasonally and spatially resolved data sets and models might be required to generate accurate evaluations of the BCP. Plain Language Summary: Each year, marine phytoplankton convert carbon dioxide into millions of tonnes of organic carbon with a fraction of it reaching the deep ocean, where it can remain for hundreds of years. The efficiency of this surface‐to‐depth carbon transfer is therefore a key determinant of the atmosphere‐ocean carbon dioxide balance. However, the variability of this transfer efficiency (TE) and its underlying causes are poorly understood, to the extent that different studies report contradicting results. We show that the existence of seasonal variability in the attenuation of sinking carbon particles can explain the observed spatial variability in annual TE and reconcile with the literature. Our findings suggest caution in interpreting results from sparse but time‐varying data sets, highlighting that seasonal variability should be considered when studying the oceanic carbon cycle. Key Points: Spatial variability in carbon transfer efficiency (TE) can be generated solely by the seasonality of flux attenuation informed by observationsSeasonality in flux attenuation can reconcile contrasting TE maps reported in the literatureResolving and understanding seasonality are key for an accurate evaluation of the biological carbon pump under climate change [ABSTRACT FROM AUTHOR]

Introduction: The Arctic sea ice extent in September (when it is at its lowest) has declined 13% Q10 per decade, and the Arctic Ocean is becoming a more Atlantic-influenced system. Rapid climate-forced changes are taking place in many high-latitude marine ecosystems. The Barents Sea is one such highlatitude shelf ecosystem, between approximately 70° and 80°N in the Norwegian Arctic. The purpose of the current study was to estimate zoobenthic blue carbon across multiple habitats within the Barents Sea (trough, basin, shelf, and shallows), potentially providing values to aid ecosystem-based management of these areas under future climate change scenarios. Method: We tested this by capture and analysis of 947 high-resolution (each 405.7 × 340.6 mm, 12 MB, 5 megapixels) seabed images at 17 sites with latitudinal cline, linked to a collection of corresponding oceanographic data. Biotas within these images were identified to one of the 14 functional groups and the density was calculated. Mean stored carbon per individual was assigned by ash mass (AM) and ash-free dry mass (AFDM) of individuals caught within Agassiz trawl deployments at the same sites. Results: Trough sites, except for one site (B16), have a low quantity of zoobenthic blue carbon compared with the shallow, shelf, and basin habitats. Discussion: The results of a previous study focused entirely on trough habitats and are therefore difficult to scale up as the basis for a meaningful estimate of across-habitat zoobenthic blue carbon in the Barents Sea. Compared with the trough and the basin, the shelf and shallow habitats of the Barents Sea are also subjected to more trawling events through demersal fisheries and showed higher zoobenthic blue carbon stock values. [ABSTRACT FROM AUTHOR]

Petrochemical producers both rely upon and generate some of the most problematic substances in the current age of socioecological crisis: fossil fuels and plastics. With mounting calls to cap fossil fuel extraction as well as plastics production, the industry appears to be caught between a rock and a hard place. Nonetheless, betting on continuously increasing global plastic demand, petrochemical production is expanding significantly. This predicament raises the question of how the industry attempts to square increasing petrochemical production with the need to address environmental issues. In recent years, leading actors in and around the industry have promoted notions of carbon circularity as a desirable mitigation strategy. In this paper, we examine this strategy, using discourse analysis to uncover what we refer to as the imaginary of circular carbon. We highlight how the circular carbon imaginary risks delaying climate mitigation by rendering alternative mitigation pathways undesirable. It does so by reconciling increased production, carbon neutrality, and circular economy in a vision of a circular carbon economy, framing the climate crisis as an issue of carbon management. In the circular carbon economy, carbon dioxide, petrochemicals, and plastics all fit as mere flows of carbon. The circular carbon imaginary thereby helps future-proof the petrochemical industry in legitimizing its carbon-intensive practises essential to the fossil world order and the plastic crisis. • We explore the circular carbon imaginary as promoted by the petrochemical industry. • It is a mitigation strategy centred around circular and diversified carbon flows. • That relies on largely unproven technologies and frames out short-term mitigation pathways. • By doing so, it risks delaying climate mitigation. [ABSTRACT FROM AUTHOR]

Phytolith-occluded carbon (PhytOC) is highly stable, and constitutes an important source of long-term C storage in agrosystems. This stored carbon is resistant to the processes of oxidation of carbon compounds. In our research phytolith content in barley (Estonia) and oat (Poland) grain and straw was assessed at field trials, with Si as a liquid immune stimulant OPTYSIL and compost fertilisation. We showed that cereals can produce relatively high amounts of phytoliths. PhytOC plays a key role in carbon sequestration, particularly for poor, sandy Polish and Estonian soils. The phytolith content was always higher in straw than in grain regardless of the type of cereals. The phytolith content in oat grains varied from 18.46 to 21.28 mg∙g-1 DM, and in straw 27.89-38.97 mg∙g-1 DM. The phytolith content in barley grain ranged from 17.24 to 19.86 mg∙g-1 DM, and in straw from 22.06 to 49.08 mg∙g-1 DM. Our results suggest that oat ecosystems can absorb from 14.94 to 41.73 kg e-CO2∙ha-1 and barley absorb from 0.32 to 1.60 kg e-CO2∙ha-1. The accumulation rate of PhytOC can be increased 3-fold in Polish conditions through foliar application of silicon, and 5-fold in Estonian conditions. In parallel, the compost fertilisation increased the phytolith content in cereals. [ABSTRACT FROM AUTHOR]