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Surf breaks are increasingly recognized as socio‐environmental phenomena that provide opportunities for biodiversity conservation and sustained benefits for local communities. Here, we examine an additional benefit from improved conservation of the ecosystems that host and surround surf breaks—their coincidence with carbon dense coastal ecosystems. Using global spatial datasets of irrecoverable carbon (defined as carbon stocks that, if lost today, could not be recovered within 30 years' time), surf break locations, ecosystem types, protected areas, and Key Biodiversity Areas, we identified 88.3 million tonnes of irrecoverable carbon held in surf ecosystems. Of this total, 17.2 million tonnes are found in Key Biodiversity Areas without formal measures of protection. These results highlight surf conservation as a potential avenue to simultaneously mitigate climate change, protect biodiversity, and promote sustainable development in coastal communities. [ABSTRACT FROM AUTHOR]

This perspective article delves into the transformative potential of alkali‐activated materials, acid‐activated materials, and geopolymers in mitigating climate change and market challenges. To harness the benefits of these materials, a comprehensive strategy is proposed. This strategy aims to integrate these materials into existing construction regulations, facilitate certification, and promote market access. Emphasizing research and innovation, the article advocates for, increased funding to refine the chemistry and production of these materials, prioritizing low‐cost alternatives and local waste materials. Collaboration between academia and industry is encouraged to expedite technological advances and broaden applications. This article also underscores the need to develop economic and business models emphasizing the long‐term benefits of these materials, including lower life‐cycle costs and reduced environmental impact. Incentivizing adoption through financial mechanisms like tax credits and subsidies is suggested. The strategy also includes scaling up production technology, fostering industrial collaboration for commercial viability, and developing global supply chains. Educational programs for professionals and regulators are recommended to enhance awareness and adoption. Additionally, comprehensive life‐cycle assessments are proposed to demonstrate environmental benefits. The strategy culminates in expanding the applications of these materials beyond construction, fostering international collaboration for knowledge sharing, and thus positioning these materials as essential for sustainable construction and climate change mitigation. [ABSTRACT FROM AUTHOR]

Local authorities are important actors in sustainability transformations, but smaller municipalities generally do not have the same capacities as larger ones to work strategically with climate‐related risks and long‐term sustainability issues. Our study analyses the efforts of two Swedish local authorities to build capacity for transformative climate governance, paying attention to how structural factors and multi‐level governance relations shape local capacity building. Drawing on interviews with municipal staff and the analysis of policy documents we show that both local authorities are increasingly applying experimental climate governance approaches. In Enköping, innovative governance processes support sustainability objectives and promote public–private collaboration. In Kiruna, the necessity to move the town centre has advanced innovation capacity but steals attention from other issues. We conclude that vertical and horizontal multi‐level governance relations facilitate capacity building, but in a national context where climate action is largely voluntary, more support is needed for smaller municipalities with limited resources to reach their climate goals. [ABSTRACT FROM AUTHOR]

In response to the climate goal of achieving carbon neutrality by 2050, efficient electrochemical energy conversion devices are garnering increasing attention. However, the enhancement of electrochemical performance using noble metal electrocatalysts, along with cost reduction and electrode fabrication, remain significant challenges. Noble metal hybrid nanostructures, possessing multiple surface functionalities, lead to outstanding electrocatalytic performances and low‐cost potential. Strain effects can bolster the bonding strength between the noble metal layers and the substrate or core layers, while simultaneously affecting electrocatalytic performance through tuning the binding strength between catalytically active sites and reactants, including intermediates. This review encapsulates the research efforts directed towards improving the performance of noble metal electrocatalysts and provides an overview of the latest advancements in controlling the surface state of noble metals by incorporating a secondary component. We discuss systematic approaches to adjusting surface strain effects on noble metals, characterization techniques, and application case studies, while extracting key design indicators for readers to consider from a macroscopic perspective. Further, we outline the challenges encountered and current solutions when advancing noble metal catalysts from theoretical mechanisms to practical use. Finally, the perspectives on the future research of noble metal surface layer control techniques were also provided. [ABSTRACT FROM AUTHOR]

Subsurface gas storage is crucial for achieving a sustainable energy future, as it helps to reduce CO2 emissions and facilitates the provision of renewable energy sources. The confinement effect of the nanopores in caprock induces distinctive thermophysical properties and fluid dynamics. In this paper, we present a multi‐scale study to characterize the subsurface transport of CO2, CH4, and H2. A nanoscale‐extended volume‐translated Cubic‐Plus‐Association equation of state was developed and incorporated in a field‐scale numerical simulation, based on a full reservoir‐caprock suite model. Results suggest that in the transition from nanoscale to bulk‐scale, gas solubility in water decreases while phase density and interfacial tension increase. For the first time, a power law relationship was identified between the capillary pressure within nanopores and the pore size. Controlled by buoyancy, viscous force and capillary pressure, gases transport vertically and horizontally in reservoir and caprock. H2 has the maximum potential to move upward and the lowest areal sweep efficiency; in short term, CH4 is more prone to upward migration compared to CO2, while in long term, CH4 and CO2 perform comparably. Thicker caprock and larger caprock pore size generally bring greater upward inclination. Gases penetrate the caprock when CH4 is stored with a caprock thickness smaller than 28 m or H2 is stored with a caprock pore size of 2–10 nm or larger than 100 nm. This study sheds light on the fluid properties and dynamics in nanoconfined environment and is expected to contribute to the safe implementation of gigatonne scale subsurface gas storage. Plain Language Summary: Aiming at the ambitious targets of net‐zero emission and global energy transition, effective technologies need to be developed and deployed with huge efforts. Subsurface gas storage is expected to play a critical role in reducing CO2 emission and providing large‐scale renewable energy. However, unforeseen gas leakage can cause potential environmental risks and energy efficiency concerns. Despite its importance, the mechanisms governing gas transport and distribution within caprocks, particularly under nanoconfinement conditions, are poorly understood. From nano‐scale and bulk‐scale thermodynamic properties predictions to field‐scale numerical simulations, this work carried out a comprehensive multi‐scale analysis to evaluate the storage security of CO2, CH4, and H2. Relationships between VLE, phase density, interfacial tension, capillary pressure and pore size, temperature, pressure and wettability were discussed, offering novel perspectives on the mechanisms governing gas leakage. Furthermore, loss potentials of different gases were compared and evaluated and the impacts of caprock thickness and pore size were examined, providing valuable insights for screening eligible storage sites. Overall, this work contributes to the development of secure and reliable gas storage techniques, supporting the goals of climate change mitigation and facilitating the transition to a net‐zero energy future. Key Points: A multi‐scale analysis is carried out to assess the loss potential of CO2, CH4, and H2 during subsurface storageMigration and distribution characteristics of gases in the caprock are investigatedShort‐term and long‐term gas storage security are analyzed and compared [ABSTRACT FROM AUTHOR]

Background Aims Methods Results Conclusions Nanotechnology, utilizing nanoparticles (NPs) with unique physicochemical properties, has significant potential in enhancing sustainable agriculture through innovations in plant nutrition, growth, and protection.This review aims to assess how nanotechnology, particularly NPs, contributes to sustainable agriculture by improving plant nutrition and growth, enhancing stress resistance, and offering solutions for phytoremediation and agricultural efficiency.We examine studies showcasing the application of NPs in agriculture, focusing on their effects on plant growth, nutrient delivery, stress mitigation, pollutant removal, and the enhancement of food shelf life through nano‐encapsulated fertilizers and nano‐sensors.NPs have demonstrated promising results in slow‐release fertilizers for targeted nutrient delivery, improved germination and physiological activity under stress, and enhanced efficiency in phytoremediation by aiding the removal of pollutants. Nano‐sensors in food packaging detect deterioration and extend food shelf life, whereas nano‐encapsulation of agrochemicals offers environment‐friendly pest and nutrient management solutions.Nanotechnology presents a forward‐looking approach to sustainable agriculture by enhancing crop productivity, resource use efficiency, and environmental protection. Continued research is essential to unlock the full potential of NPs in agriculture, emphasizing safe and efficient application methods to mitigate abiotic and biotic stresses and promote sustainability. [ABSTRACT FROM AUTHOR]

Global agricultural by‐products usually go to waste, especially in developing countries where agricultural products are usually exported as raw products. Such waste streams, once converted to “value‐added” products could be an additional source of revenue while simultaneously having positive impacts on the socio‐economic well‐being of local people. We highlight the utilization of thermochemical techniques to activate and convert agricultural waste streams such as rice and straw husk, coconut fiber, coffee wastes, and okara power wastes commonly found in the world into porous activated carbons and biofuels. Such activated carbons are suitable for various applications in environmental remediation, climate mitigation, energy storage, and conversions such as batteries and supercapacitors, in improving crop productivity and producing useful biofuels. [ABSTRACT FROM AUTHOR]

Globally, the increasing fire events in addition to climate change due to the emission of carbon dioxide (CO2) as well as other greenhouse gases exerts huge pressure on natural resources and their management. This phenomenon is more severe in the tropical region due to increasing population, urbanization, industrialization, existing pressures, and limiting conditions. In the present study, carbon (C) stock, carbon sequestration (Cseq), CO2 mitigation potential, C budget, and C flux of the seasonally dry forest ecosystem of Chhattisgarh under the influence of wildfire in the protected area and its proximity were evaluated. Four sites namely, high fire zone (HFZ), medium fire zone (MFZ), low fire zone (LFZ), and non‐fire zone (NFZ) were selected and marked based on fire return intervals (frequency) and extent of damage. The present work is a novel approach that assesses the impact of different fire frequencies on C dynamics of fire‐affected zones. The stratified sampling technique was used within a permanent plot of 1 hectare. Forest stands on each site were analyzed using 10 randomly placed quadrats (each 10 × 10 m in size) and data were collected from each site. Across the sites higher tree density was observed at NFZ and the lowest at HFZ.Total tree biomass ranged between 116.0 and 358.4 t ha−1 across the fire regimes. Total vegetation C stock ranged between 59.1 and 169.5 t ha−1 in different sites. The C mitigation and Cseq potential ranged between 186.2 and 575.3 t ha−1, and 7.1 and 15.9 t ha−1, respectively being highest in NFZ and lowest in HFZ. The species such as Anogeissus latifolia, Buchanania lanzan, Shorea robusta, Lannea coromandelica, Lagerstroemia parviflora, Ougeinia oojeinensis, Terminalia chebula, Terminalia tomentosa are the major contributor in biomass, C stock, C mitigation, and Cseq potential in different fire regimes. Thus, our findings would be highly useful in the restoration process of fire‐affected zones through the plantation of selective plant species. Therefore, the aforementioned species could be effectively utilized while going for an afforestation/reforestation program, and will be helpful in climate change adaptation and mitigation strategies under different fire zones. [ABSTRACT FROM AUTHOR]

The global climate and biodiversity crises are closely intertwined, yet no policy instrument currently tackles both jointly. This is problematic, as the lack of international platforms for designing coordinated and coherent policy frameworks that align targets across the nexus of biodiversity and climate change poses risks to nature and people. Here, we argue that the successful implementation of both the Paris Agreement and the Global Biodiversity Framework (GBF) requires a joint work programme between the United Nations Framework Convention on Climate Change (UNFCCC) and the Convention on Biological Diversity (CBD). Such a joint work programme could fill the current global governance vacuum and address critical implementation gaps, while fostering innovation and synergies in climate and biodiversity action. Based on a review of existing work programmes under the UNFCCC and interagency and joint work programmes established with the CBD, we provide a concept of how this joint programme could be set up, ideas on the type of issues it should tackle and recommendations for successful implementation. Policy implications: The UNFCCC and CBD are unique platforms for providing the evidence to, and guiding the way through the changes we need, but higher levels of integration between the biodiversity and climate change agendas are needed to plug the implementation gap between the GBF and the Paris Agreement. The upcoming Conference of the Parties (COP) for the United Nations Framework Convention on Climate Change (COP29) and the Convention on Biological Diversity (COP16) present a clear policy window for the two conventions to introduce a formal governance structure, such as the one proposed in this contribution, that brings together ideas, people, organizations and processes necessary for joining the dots on how to both stabilize our climate and recover our nature. [ABSTRACT FROM AUTHOR]

Societal transformations for addressing climate change are intensely contested and at risk of resistance and backlash to ambitious policy action. But they are frequently modeled through heuristics such as S‐curves which abstract from such conflicts, assuming increasing returns to scale as a driver of transformations. This is the case even while scholars accept the presence of political conflict in transformation processes. Within political science and allied disciplines, the notions of policy feedback and policy coalitions have been deployed to understand how such political conflicts may be understood. But these approaches risk gravitating toward an instrumental design impulse that inadvertently downplays conflict. We argue that policy action for societal transformations should be re‐conceptualized as an unfolding series of battle‐settlement events whereby heated episodic political struggles over a certain policy object or issue play out and eventually settle in ways that structure future debates while nonetheless remaining indeterminate and open to challenge or reversal. Such an approach reflects the varied empirical experiences of climate policy action to date which include both accumulation and reversal. It also helps explain trajectories of change that are discontinuous and lurching in contrast to common images of transformation as progressive and cumulative. We illustrate this approach through two cases of unfolding societal transformation on climate change: coal phaseout in the United Kingdom and renewable energy uptake in Australia. [ABSTRACT FROM AUTHOR]

Incorporating forage legumes into grasslands is a recommended climate change mitigation strategy, but accruing desired benefits from legumes is contingent upon their resilience when exposed to climate change factors (CCF). Our objective was to synthesize literature describing responses to CCF of a broad array of forage legume species, including annuals and perennials from both temperate and tropical/subtropical regions. Most‐represented species in the related literature include alfalfa (Medicago sativa L.), various Trifolium and Lotus species, rhizoma peanut (Arachis glabrata Benth.), and capitata stylo (Stylosanthes capitata Vogel). The data indicate that while CCF effects on forage legumes can be generalized, interactions among CCF, species, and site‐specific soil/climate conditions may cause variation from expected responses. In most instances, exposing forage legumes to CO2 enrichment (eCO2) increased forage accumulation (FA), but elevated temperature (eT) often reduced the magnitude of the positive response to eCO2. Photosynthetic acclimation to eCO2 occurs in non‐N‐fixing plants, but legume nodules are large C sinks and drive sustained increases in legume FA to eCO2. Legume N2 fixation and the proportion of legume N derived from N2 fixation increase with eCO2, but the magnitude of the increases lessens with eT. Legume nutritive value (NV) responses to eCO2 are less pronounced than FA responses, but decreased herbage N and greater nonstructural carbohydrate concentrations are common. Exposure to eT negatively affects NV unless intervals between defoliation events are shortened. Limited data on reproductive performance show CCF affect flower number, pollen grain morphology and viability, and behavior of pollinators, potentially influencing legume reproductive success. [ABSTRACT FROM AUTHOR]

Related Articles The Paris Agreement is an important milestone in international climate policy and the associated negotiations of the United Nations Climate Summit under the United Nations Framework Convention on Climate Change (UNFCCC). Article 6 of the Paris Agreement is a supplementary mechanism—regarding carbon markets—to reduce greenhouse gases and achieve the UNFCCC's main objective of stabilizing greenhouse gas concentrations. The 2021 United Nations Climate Summit in Glasgow (COP26) played a key role in the pursuit of this goal. Via an overview of Article 6 negotiations in past COP summits and a systematic review and qualitative meta‐synthesis of the literature leading up to COP26, I identify three arguments involving Articles 6.2, 6.4, and 6.8 behind the selected literature. I substantiate these arguments based on the meta‐evaluation of the existing literature and propose a three‐stage meta‐evaluation of the arguments on Article 6 (carbon markets) of the Paris Agreement in the context of COP26 to ascertain if the negotiations were successful in leading to requisite agreements on Article 6. I conclude that future qualitative research should focus on Articles 6.4 and 6.8 of the Paris Agreement and examine the outcomes of future climate debates to see how ideas will flow through the negotiations regarding these two articles to pursue the goal of the UNFCCC under the Paris Agreement.Jihyung Joo, Jihyung, Jouni Paavola, and James Van Alstine. 2023. “The Divergence of South Korea's Emissions Trading Scheme (ETS) from the EU ETS: An Institutional Complementarity View.” Politics & Policy 51(6): 1155–73. https://doi.org/10.1111/polp.12566.Nunes Silva, Carlos. 2012. “Policy and Evidence in a Partisan Age: The Great Disconnect—By Paul Gary Wyckoff.” Politics & Policy 40(3): 541–43. https://doi.org/10.1111/j.1747‐1346.2012.00363.x.Robles, Pedro, and Daniel J. Mallinson. 2023. “Catching up with AI: Pushing toward a Cohesive Governance Framework.” Politics & Policy 51(3): 355–72. https://doi.org/10.1111/polp.12529. [ABSTRACT FROM AUTHOR]

The climate commitment to achieving carbon neutrality before 2060 in China has been announced recently. In the context of pursuing carbon neutrality, sharing similar sources as greenhouse gases, aerosol particle and precursor emissions are projected to substantially decrease in China, which can potentially have a great impact on climate. Here, we investigate the effects of future aerosol reductions, because of achieving carbon neutrality, on solar and wind energy in China by using an earth system model. We show that significant reductions in aerosol emissions, particularly in eastern China, lead to increases in the surface downwelling shortwave radiation, surface air temperature and wind speed, which can further enhance the potential of solar and wind energy production. The findings underline that the pursuit of carbon neutrality can yield co‐benefits of not only mitigating climate change and air pollution but also fortifying the stability of renewable energy sources. Plain Language Summary: In response to China's commitment to achieve carbon neutrality by 2060, our study examines the potential impact of reducing aerosol emissions and greenhouse gases on solar and wind energy generation. Employing an earth system model, we observe significant reductions in aerosols, particularly in eastern China, resulting in increases in surface downwelling shortwave radiation, surface air temperature, and wind speed. These changes have promising implications for enhancing solar and wind energy production. Our research underscores the interconnected benefits of pursuing carbon neutrality, encompassing climate change mitigation, air quality improvement, and the enhancement of renewable energy reliability. Key Points: The effects of future aerosol reductions in China due to achieving carbon neutrality on solar and wind energy are investigatedAerosol emission reductions, especially in eastern China, increase surface downwelling shortwave radiation, temperature and wind speedClimate changes resulting from emission reductions under carbon neutrality enhance the potential of solar and wind energy [ABSTRACT FROM AUTHOR]

The EU Biodiversity Strategy 2030 aims to better protect natural ecosystems with high biodiversity and climate change mitigation potential. To achieve this goal, it is crucial to identify forests worth protecting, such as those characterized by long continuity and old age. Here, we propose a robust approach that combines historical maps from the mid‐19th century with remote sensing data to identify areas that have been forested for over 150 years, aiming to reduce the need for detailed and time‐consuming field investigations in potential conservation areas. We tested this approach in a 20,000 km2 region in the Polish Carpathians, an area likely containing many unprotected forests of high conservation value, where historical maps from the mid‐19th century are representative of much of Central Europe. Our results showed that an area of approximately 4200 km2 has been continuously forested since at least the mid‐19th century. Currently, 50% of these forests are outside protected areas, representing an important conservation opportunity. More generally, our approach can support the identification of valuable forests worth protecting before they are lost and provide useful insights for policymakers and stakeholders in the ongoing debate on the challenges of improving forest conservation in the Carpathians, and Europe more widely. [ABSTRACT FROM AUTHOR]

Although studies have explored how soil microbial diversity and soil multifunctionality respond to land‐use change at local scales, they have rarely been explored at larger scales and across different climatic and soil environmental conditions. By sampling 40 paired sites of land‐use change from natural forests to agricultural lands (including croplands and orchards) along the middle and lower Yangtze River, combined with a global meta‐analysis, we investigated the effects of land‐use change and climate on the alpha and beta diversity of soil bacterial and fungal functional groups (FGs) and their associated soil multifunctionality at a regional scale. Our results showed that land‐use change strongly changed the diversity of soil bacterial and fungal FGs and decreased multifunctionality, which was supported by our meta‐analysis at a global scale. Direct effects of land‐use change and climate and their interaction, together with changes in soil environmental variables, were the main determinants of the land‐use change‐induced changes in the diversity of soil bacterial or fungal FGs. The land‐use change‐induced decrease in multifunctionality was mainly associated with the direct effect of forest conversion, soil fertility and diversity of fungal FGs. Furthermore, climate also regulated the effects of land‐use change on multifunctionality by affecting soil fertility and fungal FGs diversity along the Yangtze River. Synthesis and applications. Taken together, our findings highlight the important effects of land‐use change, climate and their interactions on microbial diversity and multifunctionality and suggest that effective land‐use management and climate change mitigation strategies should be adopted to protect biodiversity and ecosystem function in the Yangtze River Basin. [ABSTRACT FROM AUTHOR]

Asia's contribution will be decisive for the global effort to mitigate climate change. But Asia lacks a country that could take the lead and inspire the rest of the region to accelerate its climate action. To identify countries that could fulfill such a role, this article takes a two‐step, mixed‐methods approach. First, an index is created to identify some potentially leading countries. Second, the top countries identified by the index are assessed in greater detail qualitatively. The analysis finds that China, Japan, and Singapore are the most plausible candidates to take the lead. By doing so, these countries could potentially inspire their neighbors to step up their own efforts as climate change becomes an increasingly important issue in international affairs. However, to become a leader and influence their peers, they will have to make a conscious choice and dedicated effort. [ABSTRACT FROM AUTHOR]

Do presidential climate change narratives increase related congressional attention in the United States? Narrative theory says since narratives leverage cognitive heuristics, they should focus policy‐making attention in institutions more efficiently than non‐narrative statements. This study identifies and tests climate change statements and narratives, including those focused on solutions, or "stories of hope," and those focused on problems and victims, "stories of fear," for relationships with congressional attention using time series analysis. Findings suggest a relationship between narrative and hearings, but not for non‐narrative statements and hearings. Furthermore, while narratives are related to hearings generally, stories of fear have larger effects, but only in conditions of single party control of the US Presidency and Congress. This analysis supports theory about narratives and institutional influence and offers the additional concept of stories of fear and hope as impactful on political institutions. [ABSTRACT FROM AUTHOR]

Temperature extremes exert a significant influence on terrestrial ecosystems, but the precise levels at which these extremes trigger adverse shifts in vegetation productivity have remained elusive. In this study, we have derived two critical thresholds, using standard deviations (SDs) of growing‐season temperature and satellite‐based vegetation productivity as key indicators. Our findings reveal that, on average, vegetation productivity experiences rapid suppression when confronted with temperature anomalies exceeding 1.45 SD above the mean temperature during 2001–2018. Furthermore, at temperatures exceeding 2.98 SD above the mean, we observe the maximum level of suppression, particularly in response to the most extreme high‐temperature events. When Earth System Models are driven by a future medium emission scenario, they project that mean temperatures will routinely surpass both of these critical thresholds by approximately the years 2050 and 2070, respectively. However, it is important to note that the timing of these threshold crossings exhibits spatial variation and will appear much earlier in tropical regions. Our finding highlights that restricting global warming to just 1.5°C can increase safe areas for vegetation growth by 13% compared to allowing warming to reach 2°C above preindustrial levels. This mitigation strategy helps avoid exposure to detrimental extreme temperatures that breach these thresholds. Our study underscores the pivotal role of climate mitigation policies in fostering the sustainable development of terrestrial ecosystems in a warming world. [ABSTRACT FROM AUTHOR]

Heat released from soil organic carbon (SOC) decomposition (referred to as microbial heat hereafter) could alter the soil's thermal and hydrological conditions, subsequently modulate SOC decomposition and its feedback with climate. While understanding this feedback is crucial for shaping policy to achieve specific climate goal, it has not been comprehensively assessed. This study employs the ORCHIDEE‐MICT model to investigate the effects of microbial heat, referred to as heating effect, focusing on their impacts on SOC accumulation, soil temperature and net primary productivity (NPP), as well as implication on land‐climate feedback under two CO2 emissions scenarios (RCP2.6 and RCP8.5). The findings reveal that the microbial heat decreases soil carbon stock, predominantly in upper layers, and elevates soil temperatures, especially in deeper layers. This results in a marginal reduction in global SOC stocks due to accelerated SOC decomposition. Altered seasonal cycles of SOC decomposition and soil temperature are simulated, with the most significant temperature increase per unit of microbial heat (0.31 K J−1) occurring at around 273.15 K (median value of all grid cells where air temperature is around 273.15 K). The heating effect leads to the earlier loss of permafrost area under RCP8.5 and hinders its restoration under RCP2.6 after peak warming. Although elevated soil temperature under climate warming aligns with expectation, the anticipated accelerated SOC decomposition and large amplifying feedback on climate warming were not observed, mainly because of reduced modeled initial SOC stock and limited NPP with heating effect. These underscores the multifaceted impacts of microbial heat. Comprehensive understanding of these effects would be vital for devising effective climate change mitigation strategies in a warming world. [ABSTRACT FROM AUTHOR]

Crop biomass is the reservoir of carbon (C), a valuable input to the soil, thus supporting the soil fauna and enhancing soil health. There are limited studies that compared the major cereal crops for C storage for regenerative agriculture and to optimize C sequestration strategies. The objective of this study was to quantify the extent of variation in biomass allocation and C storage between maize (Zea mays L.), sorghum (Sorghum bicolor [L.] Moench), and wheat (Triticum aestivum L.) for crop production, and C sequestration potential. The study used metadata from 40 global studies that reported on the allocation of plant biomass and C between roots and shoots of the major cereal crops. Key statistics were computed to determine the variability between genotypes for total plant biomass (Pb), shoot biomass (Sb), root biomass (Rb), root‐to‐shoot biomass ratio (Rb/Sb), total plant carbon content, shoot carbon content, root carbon content, total plant carbon stock (PCs), shoot carbon stock, root carbon stock, and root‐to‐shoot carbon stock ratio (RCs/SCs). Maize exhibited the highest variability for Pb (with a coefficient of variation [CV] of 31.2% and a mean of 4.2 ± 1.3 Mg ha−1 year−1), followed by wheat (CV of 24.2% and a mean of 1.5 ± 0.4 Mg ha−1 year−1) and sorghum (CV of 16.8% and a mean of 2.0 ± 0.8 Mg ha−1 year−1), respectively. A similar trend was observed for PCs, with maize (CV of 40.1% and mean of 1.6 ± 0.7 Mg ha−1 year−1) showing the highest total plant C stock variability, followed by wheat (24.4% and 0.2 ± 0.1 Mg ha−1 year−1) and sorghum (16.3% and 0.9 ± 0.3 Mg ha−1 year−1), respectively. Maize (with a CV of 24.4% and mean of 0.1 ± 0.03 Mg ha−1 year−1) exhibited the highest variability for Rb/Sb, while wheat (30.92% and 0.2 ± 0.05 Mg ha−1 year−1) exhibited the highest variability for RCs/SCs. Correlation analysis revealed the following significant associations: Pb and mean annual temperature (MAT) (r = −0.47), and Sb and MAT (r = −0.43), and Pb and mean annual precipitation (MAP) (r = −0.34), and Sb and MAP (r = −0.30). Rb had a strong, significant positive correlation with MAT (r = 0.72) and MAP (r = 0.85). The meta‐analysis revealed that maize and sorghum have the highest variability for Pb and plant carbon stocks, while wheat exhibited the highest variability for the below‐ground biomass and carbon stocks. The data aided in crop selection and suggested that the best cultivars could be developed and identified for production and C sequestration potential for cultivation by farmers, land rehabilitation, and climate change mitigation. Core Ideas: There is sufficient genetic variation in maize, sorghum, and wheat cultivars for manipulation of biomass and carbon allocation.Root carbon is a major contributor to soil organic carbon.Above‐ground biomass is important for atmospheric carbon sequestration. [ABSTRACT FROM AUTHOR]

Biomass estimation forms the foundation for tackling global climate issues across diverse land use systems (LUSs). A research initiative was undertaken to identify the maximum biomass allocation using an allometric approach, and to assess the carbon stock, CO2 sequestration, and carbon credit across diverse land use systems (LUSs) in the Vindhyan region of Mirzapur, Uttar Pradesh, India. This study aims to address climate change by identifying land‐use strategies that stabilize income and are easily adoptable by farmers. Tropical dry deciduous forest, agriculture, plantation, horticulture and agri‐horticulture LUSs were investigated using three combinations of custard apple (Annona squamosa), guava (Psidium guajava), bael (Aegle marmelos), mustard (Giriraj) (Brassica nigra), mustard (Pitambri) (Brassica juncea), and lentil (Lens culinaris) in an agri‐horticulture system. Seven treatments with varying carbon stocks were identified: tropical dry deciduous forest (T1) LUS (TDDFLUS); wheat based agriculture (T2) LUS (WBALUS); plantation based on teak (Tectona grandis) (T3) LUS (TBPLUS); horticulture based on karonda (Carissa carandas) (T4) LUS (KBHLUS); bael + lentil (Hul‐57) (T5) LUS (BLBLUS); guava + mustard (Giriraj) (T6) LUS (GMBLUS); and custard apple + mustard (Pitambri) (T7) LUS (CAMBLUS). The results indicate that the lowest and the highest bulk densities (ρb) were recorded in TDDFLUS and WBALUS at the depths of 0–20 cm and 20‐40 cm, respectively. The mean value of the soil organic carbon (SOC) stock ranged from 11.24–18.09 t ha−1. The average value of biomass, biomass carbon stock and biomass CO2 sequestration of seven treatments varied from 9.76–88.49 t ha−1, 4.88–44.25 t ha−1, and 17.91–162.39 t ha−1, respectively. The total carbon stock, CO2 sequestration, and carbon credit for the seven treatments varied from 16.57–64.64 t ha−1, 60.82–237.28 t ha−1 and 3040.821–11 863.89US$ ha−1, respectively. The results demonstrated that different LUSs have specific advantages and their application at farm level can encourage sustainability and increase biomass accumulation, leading to carbon sequestration. Agri‐horticulture‐based LUSs can lead to better livelihoods and can also offer numerous advantages such as increased yields of staple food crops and fruits, improved soil health, reduced soil erosion, and significant contributions to the mitigation of anthropogenic warming through CO2 sequestration. [ABSTRACT FROM AUTHOR]

The conflict between investment treaties and climate action is escalating due to recent investment arbitration cases challenging States' fossil fuel phase‐out measures as violations of investment treaty obligations. As countries continue to implement climate mitigation and adaptation measures across various industries, this tension is expected to result in a rise in climate‐related investment arbitration claims. The current literature has primarily presented the tension between investment and climate treaties as a vertical conflict, with investment treaties having a chilling effect on States' climate regulation. The common defence for States' regulation has been based on their 'right to regulate'. It remains unclear whether there exists a horizontal conflict between investment and climate treaties, primarily due to the flexible nature of climate treaty obligations. However, a sovereignty‐based justification fails to recognise the international obligation of climate action and is insufficient for reconciling the conflict. This article delves into the intricate nature of the conflict between States' climate measures and their investment treaty obligations and argues that the conflict exhibits a 'quasi‐normative' nature, given the combination of binding climate obligations, permissive implementation methods and normative expectations of ambition. The article suggests that investment treaties should include clearly defined conflict clauses that outline the scope of the conflict between investment and climate treaties and establish specific mechanisms for resolving such conflicts. [ABSTRACT FROM AUTHOR]

Climate change has caused significant hardship in sub‐Saharan Africa. As a result, Kenya and Nigeria now have statutes that focus on climate change mitigation and adaptation. Both countries are also parties to the Paris Agreement. The Kenyan Climate Change Act (2016) and the Nigerian Climate Change Act (2021) are similar in terms of their design and overarching aims. Meanwhile, certain pivotal statutory provisions in both statutes are inconsistent with their overarching aims of enhancing appropriate responses to climate change. There is considerable scope for access to justice to be enhanced in the Kenyan and Nigerian statutes. Further, despite their similarities, the divergent approaches of the statutes undermine regional coherence. Such coherence is critical to effectively addressing climate change because both regional powers face similar vulnerabilities with respect to climate change and socio‐economic challenges. This article, therefore, undertakes a comparative analysis of the Kenyan and Nigerian legal regimes in two key respects, namely, (1) institutional structures and how they impact corruption and (2) accessing justice in the context of climate litigation. The Nigerian regime is behind that of Kenya in both regards. The article concludes by examining how the Aarhus Convention and the International Access to Justice Convention can help to fill any statutory gaps concerning access to justice. [ABSTRACT FROM AUTHOR]

With increasing attention to climate change and biodiversity loss, conservation social science research on land management practices is burgeoning. Researchers have broadened their focus from protected areas to diverse types of land management to support conservation and climate mitigation. But, developing effective strategies for these issues requires an in‐depth understanding of both the socio‐psychological factors that guide landholders' decision‐making and global trends in land management practices and literature. To assess the trends and status of land management behavior research, we systematically reviewed research published between 2010 and 2020 in five seminal conservation journals. Of 11,607 articles reviewed, we identified 100 articles about land management behavior. We assessed theoretical groundings, measurement methodology, land‐use terminology and practices, ecosystem type, and geographic distribution. We identified strengths and significant gaps and weaknesses across land management research. For example, 52% of articles made no meaningful connection to theory, only 14% of papers used observed behavioral data, 86% of studies uses non‐experimental methods and researchers disproportionately measured land management behavior in developed nations (66%). We also find that language used to describe land management behavior is very heterogeneous, making it difficult to summarize land management research using traditional systematic review methods. Conducting a limited systematic review can help summarize research and also identify trends across disciplines that might otherwise missed. Results from our limited systematic review can guide future research and support the development of evidence‐based policies to mitigate climate change and biodiversity loss. [ABSTRACT FROM AUTHOR]

Quantitative climate mobility research has, so far, focused primarily on climate change impacts on migration outcomes. This focus has led to a separation between quantitative climate migration research and the broader field of migration studies. In this paper ways are proposed for quantitative research to better address the complexity in the relationship between climate change and mobility. First technical suggestions are presented to improve upon migration model setups and designs and highlight promising developments. Then it is argued that quantitative methodologies can broaden the scope of research inquiries by examining how climate mitigation and adaptation efforts influence mobility, as well as assessing how mobility itself impacts vulnerability. [ABSTRACT FROM AUTHOR]

Secondary tropical forests play an increasingly important role in carbon budgets and biodiversity conservation. Understanding successional trajectories is therefore imperative for guiding forest restoration and climate change mitigation efforts. Forest succession is driven by the demographic strategies—combinations of growth, mortality and recruitment rates—of the tree species in the community. However, our understanding of demographic diversity in tropical tree species stems almost exclusively from old‐growth forests. Here, we assembled demographic information from repeated forest inventories along chronosequences in two wet (Costa Rica, Panama) and two dry (Mexico) Neotropical forests to assess whether the ranges of demographic strategies present in a community shift across succession. We calculated demographic rates for >500 tree species while controlling for canopy status to compare demographic diversity (i.e., the ranges of demographic strategies) in early successional (0–30 years), late successional (30–120 years) and old‐growth forests using two‐dimensional hypervolumes of pairs of demographic rates. Ranges of demographic strategies largely overlapped across successional stages, and early successional stages already covered the full spectrum of demographic strategies found in old‐growth forests. An exception was a group of species characterized by exceptionally high mortality rates that was confined to early successional stages in the two wet forests. The range of demographic strategies did not expand with succession. Our results suggest that studies of long‐term forest monitoring plots in old‐growth forests, from which most of our current understanding of demographic strategies of tropical tree species is derived, are surprisingly representative of demographic diversity in general, but do not replace the need for further studies in secondary forests. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Efficient mitigation of climate change requires predictive models of forest ecosystems as sinks for atmospheric carbon. Mycorrhizal fungi are drivers of soil carbon storage in boreal forests, yet they are typically excluded from ecosystem models, because of a lack of information about their growth and turnover. Closing this knowledge gap could help us better predict future responses to climate change and guide policy decisions for sustainable management of forest ecosystems. This study provides new estimates of the production and turnover of mycorrhizal mycelial biomass and necromass. This information can facilitate the integration of mycorrhizal fungi into new predictive models of boreal forest soils. Summary: In boreal forests, turnover of biomass and necromass of ectomycorrhizal extraradical mycelia (ERM) are important for mediating long‐term carbon storage. However, ectomycorrhizal fungi are usually not considered in ecosystem models, because data for parameterization of ERM dynamics is lacking.Here, we estimated the production and turnover of ERM biomass and necromass across a hemiboreal Pinus sylvestris chronosequence aged 12 to 100 years. Biomass and necromass were quantified in sequentially harvested in‐growth bags, and incubated in the soil for 1–24 month, and Bayesian calibration of mathematical models was applied to arrive at parametric estimates of ERM production and turnover rates of biomass and necromass.Steady states were predicted to be nearly reached after 160 and 390 growing season days, respectively, for biomass and necromass. The related turnover rates varied with 95% credible intervals of 1.7–6.5 and 0.3–2.5 times yr−1, with mode values of 2.9 and 0.9 times yr−1, corresponding to mean residence times of 62 and 205 growing season days.Our results highlight that turnover of necromass is one‐third of biomass. This together with the variability in the estimates can be used to parameterize ecosystem models, to explicitly include ERM dynamics and its impact on mycorrhizal‐derived soil carbon accumulation in boreal forests. [ABSTRACT FROM AUTHOR]

Forestation is a key strategy for climate mitigation in China through its biogeochemical (BGC) effect of ecosystem carbon sequestration. Additionally, the BGC effect of forestation can be either reinforced or counteracted by concurrent biogeophysical processes (BGP effect) resulting in local land surface warming or cooling, which can be translated into CO2e (i.e., BGC effect) using a local transient climate response. Previous evaluations of the climate mitigation potential of future forestation in China have, however, focused on the BGC effect only and neglected the BGP effect, potentially leading to suboptimal forestation areas. Here, we determined priority forestation areas in China by incorporating both effects to maximize its global climate mitigation effect. Our results suggest an additional 167.2 Mha potentially suitable for forestation in China, exceeding the largest forestation target (86.8 Mha) possibly assumed by the government in 2060. The forestation‐induced BGP effect (18.7 ± 61.9 tCO2e ha−1) largely reinforces the BGC effect (458.2 ± 92.6 tCO2e ha−1) in China, yielding a total climate mitigation effect of 476.9 ± 114.2 tCO2e ha−1 over 40 years (2021–2060). Under the 2060 forestation target, considering both BGC and BGP effects will displace 17.7% (15.3 Mha) of the forestation area derived by considering the BGC effect alone. Integrating both BGC and BGP effects will lead to a CO2 uptake of 28.8 GtCO2e by 2060, 3.9 GtCO2e higher than the value obtained when considering the BGC effect only. Our results highlight the importance of considering BGP effect when making forestation policies for climate mitigation. Plain Language Summary: Forestation plays a crucial role in mitigating climate change through both carbon sequestration (biogeochemical or BGC effect) and modification of land surface temperature (biogeophysical or BGP effect). Maximizing forestation contribution to global climate mitigation requires maximizing the collective effects of both BGC and BGP through converting BGP to BGC, as temperature change is fundamentally driven by atmospheric CO2 changes which are further influenced by forestation BGC effect. However, previous evaluations of China's forestation potential almost completely focused on the BGC effect. This study identified optimal forestation areas to maximize their global climate mitigation effect in China by considering both BGC and BGP effects. Considering both effects will displace 17.7% (15.3 Mha) of forestation areas determined by considering only the BGC effect under the 2060 forestation target. Considering both effects also leads to a higher CO2 uptake of 3.9 GtCO2e than the value when considering the BGC effect only by 2060. Forestation‐induced BGC and BGP effects mostly work in synergy in China, mutually enhancing the overall climate benefits. Our findings have implications for future forestation policy in China to maximize its contribution to global climate mitigation. Key Points: The biogeophysical (BGP) effect should be included in the traditional forestation policies considering only biogeochemical (BGC) effectConsidering BGC and BGP effects will lead to 17.7% of forestation area being displaced, compared to considering the BGC effect only by 2060Integrating BGC and BGP effects exhibits a 15.8% (3.9 GtCO2e) increase in CO2 uptake by 2060 [ABSTRACT FROM AUTHOR]

Understanding the climate and carbon cycle response to negative CO2 emissions is important for developing climate mitigation strategies that aim to limit global warming to a specific threshold. In this study, using a coupled climate and carbon cycle model, a novel set of nine stylized simulations are conducted with cumulative emissions of 1,000 GtC, 2,000 GtC, and 5,000 GtC over 150, 250, and 500 years, followed by identical cumulative negative emissions so that the net cumulative emissions are zero. On millennial‐timescales, the climate system returns close to the preindustrial state, independent of the emission and removal pathways. However, the thermal and biogeochemical inertia of the ocean play an important role in determining the climate and carbon cycle response during the emission and removal phases. When zero net emissions are reached, surface air temperature is larger by 0–1°C than the preindustrial state, and the atmospheric CO2 concentration is less by 12–29 ppm. These changes increase with both the magnitude and duration of the emission and removal pulses. In contrast, hysteresis in the relationship between global mean surface temperature and cumulative carbon emissions increases with the magnitude but decreases with the duration of emission and removal pulses. Our study highlights the role of ocean inertia in the asymmetry in climate response to emissions and removals and indicates that an earlier emission reduction implying emission/removal pathways with smaller magnitudes and shorter durations for the positive and negative emission pulses would avoid larger climate and carbon cycle impacts on centennial‐timescales. Plain Language Summary: In this study, we examine the climate system response to a set of scenarios where emissions are followed by the removal of all carbon emitted into the atmosphere. We find that the climate system returns to preindustrial state on millennial timescales independent of emission and removal pathways. However, larger changes in the climate system at the end of removals (on centennial timescales) are simulated for a larger magnitude and longer duration of the emission and removal pulses. Since a delay in emission reduction implies a larger magnitude and longer duration for the emissions and consequently larger magnitude and longer duration for the removals to bring the climate state to preindustrial conditions, an earlier emission reduction would help to avoid large climate and carbon cycle impacts on centennial‐timescales. Key Points: The climate system response to net zero emissions is path independent on millennial timescalesOn centennial time scales, the climate system response to net zero emissions depends on the magnitude and duration of emission pulsesA larger magnitude and longer duration for the emission pulses lead to longer delays in climate response on centennial timescales [ABSTRACT FROM AUTHOR]

Forests are a large carbon sink and could serve as natural climate solutions that help moderate future warming. Thus, establishing forest carbon baselines is essential for tracking climate‐mitigation targets. Western US forests are natural climate solution hotspots but are profoundly threatened by drought and altered disturbance regimes. How these factors shape spatial patterns of carbon storage and carbon change over time is poorly resolved. Here, we estimate live and dead forest carbon density in 19 forested western US ecoregions with national inventory data (2005–2019) to determine: (a) current carbon distributions, (b) underpinning drivers, and (c) recent trends. Potential drivers of current carbon included harvest, wildfire, insect and disease, topography, and climate. Using random forests, we evaluated driver importance and relationships with current live and dead carbon within ecoregions. We assessed trends using linear models. Pacific Northwest (PNW) and Southwest (SW) ecoregions were most and least carbon dense, respectively. Climate was an important carbon driver in the SW and Lower Rockies. Fire reduced live and increased dead carbon, and was most important in the Upper Rockies and California. No ecoregion was unaffected by fire. Harvest and private ownership reduced carbon, particularly in the PNW. Since 2005, live carbon declined across much of the western US, likely from drought and fire. Carbon has increased in PNW ecoregions, likely recovering from past harvest, but recent record fire years may alter trajectories. Our results provide insight into western US forest carbon function and future vulnerabilities, which is vital for effective climate change mitigation strategies. Plain Language Summary: We investigated the role of western US forests as natural climate solutions by analyzing current forest carbon storage and trends from 2005 to 2019 across 19 forested regions. We found that the Pacific Northwest stores the most carbon, while the Southwest stores the least. Climate, wildfires, and human activities determined carbon amounts. For instance, climate is important in the Southwest and Lower Rockies, while wildfires impact the entire western US, but particularly the Upper Rockies and California. Human activities like harvesting and private ownership, decrease carbon, particularly in the Pacific Northwest. Since 2005, live carbon has declined in many western US areas, likely due to drought and fires. The study highlights the vulnerability of western US forests to climate‐related and human threats to carbon, providing crucial insights for effective climate change mitigation strategies. Understanding these dynamics is essential for scientists, policymakers, and educators working toward sustainable forest management and climate solutions in the region. Key Points: Live carbon has declined across much of western United States forests, likely due to drought and fire, resulting in an increase in dead carbonIn the Pacific Northwest (PNW), harvest led to reduced carbon, but recovery from past harvest likely caused carbon to increase since 2005Our results provide a baseline from which to evaluate future changes and inform management strategies [ABSTRACT FROM AUTHOR]

The architecture, engineering, and construction industry is undergoing a significant shift, steering buildings away from resource‐intensive processes toward becoming instruments for climate mitigation. In this transformative landscape, integrating circular bio‐based alternatives and reducing emissions through biotechnological and enzymatic processes have significant potential. Specifically, mycelium‐bound composites have emerged as renewable alternatives for new materials and added‐value wood products. Despite their numerous advantages, integrating these materials into current engineering practices presents challenges deriving from the complex nature of the material´s production process and the transfer from the laboratory to the industrial scale. In this regard, the design and engineering of novel controlled environments are fundamental in maintaining optimal growth conditions during material production. This, in turn, influences the overall material performance and potential use in construction. [ABSTRACT FROM AUTHOR]

The objective of this paper is to review how Science and Technology Studies (STS) has contributed to climate change mitigation research. We focus on large‐scale infrastructures as a key topic of both mitigation efforts and recent STS scholarship. The paper assesses the conceptual and methodological treatments in this field, uses literature evidence to identify research gaps, and suggests potential topics for future research. Our research firstly contributes to the use of STS approaches in the novel field of climate change mitigation infrastructure, asking how scholarship in the field has learned from STS and developed STS further. Second, we examine how infrastructures are approached in this literature and conclude that the reviewed works almost exclusively associate infrastructure with physical supply systems. This is paradoxical since several of them also advocate a socio‐technical perspective on infrastructures, which would require much more substantiation of the social aspects than they seem to provide. Third, we explore the fits between theoretical frameworks and methods in this field and discover a strong reliance on case studies, literature reviews, and theoretical‐conceptual discussions. This situation suggests that methodological advancements in STS infrastructure studies has still been untapped in this area. This article is categorized under:The Carbon Economy and Climate Mitigation > Decarbonizing Energy and/or Reducing Demand [ABSTRACT FROM AUTHOR]

In February 2019, Representative Alexandria Ocasio‐Cortez and Senator Ed Markey introduced into the US Congress a non‐binding resolution for a Green New Deal, with the aim to catalyze policies and programs to rapidly decarbonize the US economy while achieving wider progressive economic, social and environmental goals. This motion sparked widespread interest, in and beyond the US, in the potential for more ambitious and solidaristic climate policy under the banner of a Green New Deal (GND). This Overview, after introducing the history of the GND concept and exploring its dimensions in theory, provides a snapshot of GNDs proposed (or adopted/enacted) by politicians, candidates for political office, political parties and governments around the world in the period 2019–2022. Drawing on theories of comparative politics and comparative political economy, the Overview illuminates key patterns in the prevalence and content of this set of GND proposals, as well as their ideological underpinnings and implicit "theories of change." Specifically, it ventures that: GND policies are more commonly proposed in high‐income, industrialized democracies; variation in GNDs' prevalence and content are associated with varieties of capitalism and electoral institutions; GND policies are more commonly proposed by left‐of‐center parties and candidates; and GNDs are being proposed at all levels of government, but their content is shaped by constraints on government powers. On the basis of this analysis, the concluding section proposes a detailed research agenda on GNDs, with an emphasis on comparative research. This article is categorized under:The Carbon Economy and Climate Mitigation > Benefits of MitigationPolicy and Governance > National Climate Change PolicyPolicy and Governance > Multilevel and Transnational Climate Change Governance [ABSTRACT FROM AUTHOR]

Synthesizing the extensive and ever‐growing climate change literature is becoming increasingly challenging using conventional review processes, yet is crucial to understand key trends, including knowledge and policy related gaps, managing widespread impacts, and prioritizing future efforts. Here, we employ a systematic approach to interrogate ~130,000 international peer‐reviewed climate change articles published between 1990 and 2021. We examine the time–space evolution of research topics and international collaborations, providing insights into broad scale climate change research themes, how they are developed and/or are interconnected. Our analyses indicate that significant thematic adjustments have occurred over the past three decades. Whilst all major areas of climate research have grown in output metrics, there has been a relative shift from understanding the physical science basis toward evaluating climate change impacts, adaptation, and mitigation. There has also been a significant internationalization of climate research with the ratio of international over domestic research increasing from 0.05 in 1990 to nearly 0.60 in 2021. These findings reveal a growing need for collective and coupled adaptation‐mitigation actions to address climate change. The repeatable method and overall results presented herein can help to complement existing large‐scale literature assessments, such as future IPCC reports. This article is categorized under:Climate, History, Society, Culture > Disciplinary PerspectivesIntegrated Assessment of Climate Change > Methods of Integrated Assessment of Climate Change [ABSTRACT FROM AUTHOR]

Accurate modeling of snow depth (SD) processes is critical for understanding global energy balance changes, affecting climate change mitigation strategies. This study evaluates the Coupled Model Intercomparison Project Phase 6 (CMIP6) model performance in simulating daily SD across Canada. We assess CMIP6 outputs against observed data, focusing on daily SD averages, snow cover durations, and rates of accumulation and depletion, alongside annual SD peaks for 11 major Canadian catchments. Our findings reveal that CMIP6 simulations generally overestimate daily SD by 57.7% and extend snow cover duration by 30.5 days on average. While three models (CESM2, UKESM1‐0‐LL and MIROC6) notably align with observed annual SD peaks, simulation biases suggest the need for enhanced model parameterization to accurately capture snow physics, particularly in regions with permanent snow cover and complex terrains. This analysis underscores the necessity of refining CMIP6 simulations and incorporating detailed geographical data for better SD predictions. Plain Language Summary: Precise simulations of snow depth (SD) are crucial for understanding changes in the Earth's energy balance and helping efforts to combat climate change. In this research, we evaluate how well the latest phase of the Coupled Model Intercomparison Project (CMIP6) can simulate the daily SD across Canada. By comparing these simulations to various SD data sets, we looked at average daily SD, how long snow remains on the ground, and how quickly it accumulates or melts away, focusing on 11 major catchments in Canada. Our study found that the CMIP6 models tend to simulate more SD, by about 57.7% on average, and suggest that snow cover remains around 30.5 days longer than observed durations. Although three specific models excel in matching the annual peak of daily SD, we noticed biases that point to a need for improving how these models represent various land covers. Our findings highlight the importance of making these models more accurate by using more detailed information about land cover properties, which helps better predict SD and understand its role in climate change. Key Points: Coupled model intercomparison project phase 6 (CMIP6) simulations mostly overestimate the average daily SD values by a median of 57.7% (6.9 cm)The average snow cover duration is overestimated by 30.5 days compared to station data, confirmed by the CMC data setCMIP6 simulations relatively capture extremes well, with a median bias of 12.73% [ABSTRACT FROM AUTHOR]

Related Articles Many countries are implementing carbon taxation to limit emissions, and this provides a new form of tax revenue. Studies have taken up the question of what forms of expenditure from carbon taxation receive public support and whether ‘revenue recycling’ can improve support for carbon taxation. However, public attitudes are ambiguous. We argue that some of the diverse findings partly reflect that previous studies have lacked the trade‐offs that come with expenditures and that we need to expand focus beyond what the average citizen wants. Therefore, we use an approach where members of the Danish public are asked how they would like to divide the total sum of carbon tax revenues between eight specific areas. We employ hierarchical cluster analysis, which shows a diverse field of groups. This reveals that, while generally popular, expenditures toward climate mitigation and adaptation need to be complemented by social spending to achieve broader support.Ike, Vivian. 2020. “The Impact of Veto Players on Incremental and Drastic Policy Making: Australia's Carbon Tax Policy and Its Repeal.” Politics & Policy 48(2): 232–64. https://doi.org/10.1111/polp.12346.Lachapelle, Erick, Thomas Bergeron, Richard Nadeau, Jean‐François Daoust, Ruth Dassonneville, and Éric Bélanger. 2021. “Citizens' Willingness to Support New Taxes for COVID‐19 Measures and the Role of Trust.” Politics & Policy 49(3): 534–65. https://doi.org/10.1111/polp.12404.Tuxhorn, Kim‐Lee, John D'Attoma, and Sven Steinmo. 2021. “Do Citizens Want Something for Nothing? Mass Attitudes and the Federal Budget.” Politics & Policy 49(3): 566–93. https://doi.org/10.1111/polp.12406. [ABSTRACT FROM AUTHOR]

Despite the importance of understanding the urban emission characteristics of greenhouse gases (GHGs) and air pollutants, few studies have conducted integrated assessments across diverse urban environments. Herein, we conducted a comprehensive evaluation of the emission characteristics of GHGs and air pollutants in seven cities in the Northern Hemisphere using ground‐based Fourier transform spectrometers. Our analysis primarily focused on emission ratios of excess column‐averaged dry‐air mole fractions of carbon monoxide (CO) to carbon dioxide (CO2) (∆XCO:∆XCO2) and those of methane (CH4) to CO2 (∆XCH4:∆XCO2). We found that the emission ratios varied significantly across cities. Xianghe (China) and Pasadena (USA), known for severe air pollution, showed the highest emission ratios. Notably, Seoul (South Korea) showed lower ∆XCO:∆XCO2 (3.32 ± 0.10 ppb/ppm) but relatively higher ∆XCH4:∆XCO2 (4.85 ± 0.04 ppb/ppm), which was comparable to the ∆XCH4:∆XCO2 value of Xianghe (5.15 ± 0.10 ppb/ppm), suggesting that targeted CH4 reduction strategies may be required for climate change mitigation in Seoul. Plain Language Summary: Many cities experience significant greenhouse gas and air pollutant emissions. We comprehensively analyzed the characteristics of these emissions using ground‐based solar‐viewing Fourier transform spectrometers (FTSs) in Northern Hemisphere cities including Seoul (South Korea), Thessaloniki (Greece), Tsukuba (Japan), Karlsruhe (Germany), Xianghe (China), Pasadena (USA), and Paris (France). First, we focused on variations in carbon dioxide (CO2), methane (CH4), and carbon monoxide (CO). Based on these variations, their emission ratios were estimated in terms of excess column‐averaged dry‐air mole fractions of CO to CO2 (∆XCO:∆XCO2) and CH4 to CO2 (∆XCH4:∆XCO2) in urban sites. We found that the emission ratios differed across cities. For example, Xianghe and Pasadena, which generally exhibit high levels of air pollution, had the highest emission ratios. However, Seoul had lower emission ratios of ∆XCO:∆XCO2, but higher levels of ∆XCH4:∆XCO2. This study suggests that ground‐based Fourier transform spectrometer measurements can be used as a tool for comprehensively evaluating the emission characteristics of greenhouse gases and air pollutants in urban environments. Furthermore, extending our study to longer periods and more sites could further aid in formulating effective mitigation strategies for climate change. Key Points: We comprehensively assessed the emission characteristics of greenhouse gases and air pollutants in seven cities in the Northern HemisphereGround‐based Fourier transform spectrometers offers a comprehensive analysis of the urban emission characteristics of greenhouse gases and air pollutantsOur results can further support effective strategies for mitigating climate change [ABSTRACT FROM AUTHOR]

Peatland restoration is seen as a key nature‐based solution to tackle climate change and biodiversity loss. In Europe, nearly 50% of peatlands have been drained during the last decades, which have shifted their soils to carbon dioxide (CO2) sources. Soils of forestry‐drained peatlands are known to vary from CO2 sources to small sinks depending on their fertility and wetness. When peatlands are restored, it can be expected that rates of CO2 and methane exchange will vary depending on site fertility and wetness. We generated seven restoration pathways with different starting and end points and assessed the climate impacts of them. The GHG emission coefficients were compiled from literature, and radiative forcing was calculated for a 500‐year time period since restoration. All seven restoration pathways improved carbon sink capacity; however, the climate impact differed from cooling to warming. The highest cooling impact occurred in a pathway leading from nutrient‐rich drained peatlands toward tree‐covered spruce or pine mires. Warming impacts occurred in a pathway leading from nutrient‐poor drained peatlands toward open peatlands. The results of this study can be used to help identify peatland sites and restoration targets to maximize climate change mitigation from restoration. In practice, however, restoration has to fulfill other targets, such as biodiversity safeguarding, improvement of hydrological conditions, and socio‐economic aspects. Fulfilling all targets simultaneously requires compromises on all targets. [ABSTRACT FROM AUTHOR]

Natural forests are crucial for climate change mitigation and adaptation, but deforestation and degradation challenges highly reduce their value. This study evaluates the potential of natural forest carbon stock and the influence of management interventions on enhancing forest carbon storage capacity. Based on forest area cover, a study was conducted in nine purposely selected forest patches across various forest ecosystems. Data on diameter, height, and environmental variables from various forest management approaches were collected and analyzed with R Ver. 4.1. The findings revealed a substantial difference (p.029) in carbon stock between environmental variables and management interventions. The findings revealed a strong connection between environmental variables and the overall pool of carbon stock within forest patches (p.029). Carbon stocks were highest in the Moist‐montane forest ecosystem (778.25 ton/ha), moderate slope (1019.5 ton/ha), lower elevation (614.50 ton/ha), southwest‐facing (800.1 ton/ha) and area exclosures (993.2 ton/ha). Accordingly, natural forests, particularly unmanaged parts, are sensitive to anthropogenic stresses, decreasing their ability to efficiently store carbon. As a result, the study highlighted the importance of sustainable forest management, particularly area exclosures and participatory forest management, in increasing forest carbon storage potential. [ABSTRACT FROM AUTHOR]

Rising Arctic temperatures pose a threat to the large carbon stores trapped in Arctic permafrost. To assess methane emissions in high‐Arctic regions, we analyzed atmospheric data from Alaska and Siberia using two methods: (a) a wind sector approach to calculate emission changes based on concentration enhancements using wind direction, and (b) an inversion method utilizing a high‐resolution atmospheric transport model. Incorporating data after 2015, we observed a significant rise in methane emissions (0.018 ± 0.005 Tg yr−2 from 2000 to 2021) from Alaska's North Slope, indicating a shift from previous analyses. We find 34%–50% of yearly emissions occurred in the late season (September–December) consistently across multiple years and regions, which is historically underestimated in models and inventories. Our findings reveal significant changes occurring in the Arctic, highlighting the crucial role of long‐term atmospheric measurements in monitoring the region, especially during the cold season. Plain Language Summary: The Arctic is undergoing dramatic changes with temperatures increasing at four times the global average. This increase in temperature threatens to thaw the large stores of frozen carbon in Arctic soils which can be released as methane, a more potent greenhouse gas than carbon dioxide. We use measurements of methane in the atmosphere from four Arctic Ocean coastal stations to quantify emissions from the surface. We find that emissions from the North Slope of Alaska have been increasing over the past three decades, which reflects a change from previous analyses. Additionally, we show large and consistent emissions from September to December across multiple Arctic regions. This season has traditionally been underestimated in global methane budgets and providing accurate methane quantification is vital for climate change mitigation. Our results show that important change is occurring in the Arctic, and long‐term atmospheric data can be used to monitor this change, particularly in the cold season. Key Points: Increasing tundra methane emissions from the Alaskan North Slope from 1986 to 2021 are now detected through long‐term atmospheric measurementsEmissions from the late season (September–December) are found to be persistent across multiple years and from three high Arctic regionsLate season underestimation of emissions in models and inventories is attributed to an underestimation of the emitting area [ABSTRACT FROM AUTHOR]

Although afforestation is a potential strategy to mitigate climate change by sequestering carbon, its potential biophysical effects on climate, such as regulating surface albedo, evapotranspiration, and energy balance, have not been fully incorporated into climate change mitigation strategies. This is partly due to the challenges associated with modeling the complex bidirectional interactions between vegetation and climate. In this study, we assess the impact of afforestation on low cloud cover using a regional climate model (RCM) and Earth observation data, applying a space‐for‐time approach to overcome limitations that may arise from comparing satellite and RCM results, such as different background climate conditions or different extents of land cover change. Our results show a consistent increase in low cloud cover in Europe due to afforestation in both datasets (3.71% and 3.56% on average, respectively), but the magnitude and direction of this effect depend on various factors, including location, seasonality, and forest type. These results suggest that afforestation can have important feedbacks on the climate system, and that its biophysical effects must be considered in climate change mitigation strategies. Furthermore, we emphasize the role of the modeling community in developing accurate and reliable approaches to assess the biophysical effects of land cover change on climate. Plain Language Summary: Although forests can help combat climate change by capturing carbon dioxide, we haven't fully considered the potential impact they can have on the climate in terms of biophysical factors such as surface reflectivity, evaporation, and energy balance. This is because it's challenging to accurately model the complex interactions between forests and climate. In this study, we used a regional climate model and Earth observation data to examine how forests affect the amount of low‐lying clouds. We used a method that compares satellite and model data to overcome limitations arising from different climate conditions and changes in land cover. Our findings consistently show that forests increase the coverage of low clouds in Europe. However, the specific effects depend on factors such as the location, season, and forest type. These results indicate that forests can have significant impacts on the climate system, and it is important to consider these effects when developing climate change strategies. We also emphasize the need for accurate modeling to better understand how changes in forest cover influence the climate. Key Points: Forests increase the amount of low clouds in EuropeForests impact climate beyond carbon sequestration [ABSTRACT FROM AUTHOR]

Widespread adoption of regenerative agriculture practices is an integral part of the US plan to achieve net‐zero greenhouse gas emissions by 2050. National incentives have particularly increased for the adoption of cover crops (CCs), which have presumably large carbon (C) sequestration potential. However, assessments of national CC climate benefits have not fully considered regional variability, changing C sequestration rates over time, and potential N2O trade‐offs. Using the DayCent soil biogeochemical model and current national survey data, we estimate CC climate change mitigation potential to be 39.0 ± 24.1 Mt CO2e year−1, which is 45%–65% lower than previous estimates, with large uncertainty attributed to N2O impacts. Three‐fourths of this climate change mitigation potential is concentrated in the North Central, Southern Great Plains and Lower Mississippi regions. Public investment should be focused in these regions to maximize CC climate benefits, but the national contribution of CC to emissions targets may be lower than previously anticipated. [ABSTRACT FROM AUTHOR]

Alkanes, single carbon methane to long‐chain hydrocarbons (e.g. hexadecane and tetradecane), are important carbon sources to anaerobic microbial communities. In anoxic environments, archaea are known to utilize and produce methane via the methyl‐coenzyme M reductase enzyme (MCR). Recent explorations of new environments, like deep sea sediments, that have coupled metagenomics and cultivation experiments revealed divergent MCRs, also referred to as alkyl‐coenzyme M reductases (ACRs) in archaea, with similar mechanisms as the C1 utilizing canonical MCR mechanism. These ACR enzymes have been shown to activate other alkanes such as ethane, propane and butane for subsequent degradation. The reversibility of canonical MCRs suggests that these non‐methane‐activating homologues (ACRs) might have similar reversibility, perhaps mediated by undiscovered lineages that produce alkanes under certain conditions. The discovery of these alternative alkane utilization pathways holds significant promise for a breadth of potential biotechnological applications in bioremediation, energy production and climate change mitigation. [ABSTRACT FROM AUTHOR]

The text discusses the Eastern Sociological Society's (ESS) 2024 Annual Meeting, which had a theme focused on the social aspects of the climate crisis. The conference featured various sessions and panels that explored sociological contributions to understanding and addressing the climate crisis. The text highlights the increasing integration of climate-related research and scholarship within the discipline of sociology, as well as the importance of building on prior work and fostering inclusivity within the field. The author encourages other professional associations to prioritize climate-related themes in their conferences and emphasizes the need for more diverse and accessible events. [Extracted from the article]

When young people engage with climate change education, they are often left feeling disempowered and daunted. But past research has shown that there are ways to design and deliver climate change education that can be empowering and enabling. The delivery of climate change education was further challenged in 2020 by the shift to online learning driven by the COVID‐19 pandemic restrictions. However, the challenges of the pandemic context also offered an opportunity to engage new audiences and establish new collaborations in climate change education. In this paper, we explore how the shift to online research, collaboration and education can also be harnessed to develop interdisciplinary coastal adaptation training for young people interested in better understanding the complexities of our coastal environments. The resulting 'More than Maps' framework draws on qualitative and quantitative data collected over a two‐year programme focused on the design and delivery of an international climate change research capacity building workshop series, across the United Kingdom, Ghana, Jamaica and Australia. Carried out by an interdisciplinary team of early career researchers and established academics, 15 workshops were developed on coastal adaptation research methods, targeting a range of 'young' audiences who are and will continue to be impacted by climate change. Building on reflections from the workshops' design and delivery, we developed a scalable framework to aid researchers in sharing open‐access, replicable methods for studying climate change mitigation and adaptation. This work demonstrates that our workshop participants had increased confidence, sought to apply learned methods to other contexts, and wanted to share this knowledge with others. We conclude that the COVID‐19 online workspace facilitated rather than hindered the international collaboration and delivery of these coastal adaptation research methods workshops, and we provide best practice tips to researchers delivering climate change education. [ABSTRACT FROM AUTHOR]

Land use and land cover changes (LULCCs) can influence surface temperature through local and nonlocal biophysical processes, which remain inadequately addressed. In this study, we separate the local and nonlocal effects of historical (1850–2014) LULCCs based on model outputs from the Coupled Model Intercomparison Project Phase 6. We also attempt to explore the sources of intermodel differences in the effects of LULCCs. The multimodel mean shows a cooling effect of −0.05°C (with an intermodel range of −0.24–0.06°C) at the global scale due to cropland and pastureland expansion, consisting of dominant nonlocal cooling of −0.06°C (with an intermodel range of −0.26–0.06°C) and slight local warming of 0.01°C (with an intermodel range of −0.01–0.05°C). The modeling results show some clear consistency in the effects of LULCCs despite considerable intermodel uncertainties. The local effects cause warming at low latitudes and cooling in boreal regions via changes in upward shortwave radiation and sensible and latent heat fluxes. The nonlocal effects mainly cause cooling via decreases in downward longwave radiation and increases in upward shortwave radiation. Intermodel differences in the total effects are dominated by those in the nonlocal effects, which are further attributed to divergent changes in downward longwave radiation and sensible heat flux across the models. This study highlights the importance of the nonlocal effects of LULCCs in terms of strength and intermodel uncertainty, with implications for designing land‐based solutions aimed at climate change mitigation. Plain Language Summary: Land use and land cover changes (LULCCs) can alter surface properties and thereby influence surface temperature through land–atmosphere interactions. LULCCs influence the climate not only at the location of LULCCs (local effects) but also elsewhere (nonlocal effects) through atmospheric and oceanic feedbacks. However, the local and nonlocal effects of realistic LULCCs still lack explicit investigation. In this study, we quantify the local and nonlocal effects of historical (1850–2014) LULCCs and their intermodel differences based on a set of simulations from four earth system models. The multimodel mean suggests that historical cropland and pastureland expansion has caused a nonlocal cooling effect of −0.06°C and a local warming effect of 0.01°C, creating a net cooling effect of −0.05°C at the global scale. The local and nonlocal effects of LULCCs can be attributed to changes in surface fluxes and atmospheric feedbacks, whereas the strength and sign vary substantially across the models. Large intermodel differences in the total effects of LULCCs mostly result from those in the nonlocal effects. This study highlights the importance of the nonlocal effects of LULCCs and has implications for developing land‐use strategies aimed at climate change mitigation. Key Points: The local and nonlocal biophysical effects of historical land use and land cover changes (LULCCs) are investigated using CMIP6 modelsThe multimodel mean shows that, overall, historical LULCCs cool the land surface through nonlocal processesThe intermodel divergence in the total effects of historical LULCCs mainly results from low intermodel agreement on the nonlocal effects [ABSTRACT FROM AUTHOR]

An accurate quantification of global methane sources and sinks is imperative for assessing realistic pathways to mitigate climate change. A key challenge of quantifying the Global Methane Budget (Saunois et al., 2020, https://doi.org/10.5194/essd‐12‐1561‐2020) is the lack of consistency in uncertainties between sectors. Here we provide a new perspective on bottom‐up (BU) and top‐down (TD) methane uncertainties by using an expert opinion analysis based on a questionnaire conducted in 2021. Expectedly, experts rank highest uncertainty and lowest confidence levels in the Global Methane Budget related to natural sources in BU budgets. Here, we further reveal specific uncertainty types and introduce a ranking system for uncertainties in each sector. We find that natural source uncertainty is related particularly to driver data uncertainty in freshwater, vegetation, and coastal/ocean sources, as well as parameter uncertainty in wetland models. Reducing uncertainties, most notably in aquatic and wetland sources will help balance future BU and TD global methane budgets. We suggest a new methane source partitioning over gradients of human disturbance and demonstrate that 76.3% (75.8%–79.4%) or 561 (443–700) Tg CH4 yr−1 of global emissions can be attributed to moderately impacted, man‐made, artificial, or fully anthropogenic sources and 23.7% (20.6%–24.2%) or 174 (115–223) Tg CH4 yr−1 to natural and low impacted methane sources. Finally, we identify current research gaps and provide a plan of action to reduce current uncertainties in the Global Methane Budget. Plain Language Summary: To effectively address climate change, it's crucial to gain a better understanding of the difficulties involved in estimating global methane sources and sinks. One of the key challenges in this process are the varying levels of uncertainty associated with different sectors responsible for methane emissions and methane uptake. In this study, we conducted a survey to gather expert opinions regarding the uncertainty of methane data. The experts highlighted that the Global Methane Budget has the highest uncertainty and lowest confidence levels when it comes to natural sources in the bottom‐up budgets. This uncertainty primarily stems from uncertain data related to natural sources like freshwater, vegetation, and coastal/ocean areas, as well as the parameters used in wetland models. We show that 76.3% of all global methane emissions are related to human‐impact or fully man‐made. Additionally, we identify existing gaps in research and lay out a plan of action to reduce the current uncertainties associated with the Global Methane Budget. This effort will contribute to a more accurate understanding of methane's role in climate change mitigation. Key Points: Highest uncertainty and lowest confidence levels were identified in bottom‐up natural emissions in the Global Methane BudgetHigh driver data uncertainties are associated with freshwater, vegetation, and coastal/ocean methane sourcesNew methane source partitioning reveals 76% of global emissions are related to moderate to high levels of anthropogenic impacts [ABSTRACT FROM AUTHOR]

Stratospheric aerosol injection (SAI) has been proposed as a potential supplement to mitigate some climate impacts of anthropogenic warming. Using Community Earth System Model ensemble simulation results, we analyze the response of temperature and precipitation extremes to two different SAI strategies: one injects SO2 at the equator to stabilize global mean temperature and the other injects SO2 at multiple locations to stabilize global mean temperature as well as the interhemispheric and equator‐to‐pole temperature gradients. Our analysis shows that in the late 21st century, compared with the present‐day climate, both equatorial and multi‐location injection lead to reduced hot extremes in the tropics, corresponding to overcooling of the mean climate state. In mid‐to‐high latitude regions, in comparison to the present‐day climate, substantial decreases in cold extremes are observed under both equatorial and multi‐location injection, corresponding to residual winter warming of the mean climate state. Both equatorial and multi‐location injection reduce precipitation extremes in the tropics below the present‐day level, associated with the decrease in mean precipitation. Overall, for most regions, temperature and precipitation extremes show reduced change in response to multi‐location injection than to equatorial injection, corresponding to reduced mean climate change for multi‐location injection. In comparison with equatorial injection, in response to multi‐location injection, most land regions experience fewer years with significant change in cold extremes from the present‐day level, and most tropical regions experience fewer years with significant change in hot extremes. The design of SAI strategies to mitigate anthropogenic climate extremes merits further study. Plain Language Summary: Injecting SO2 into the stratosphere to deflect incoming sunlight back to space has been proposed as a possible means to counteract anthropogenic warming. Previous studies focused on the response of the mean climate change to SO2 injection. Here we analyze how SO2 injection would affect climate extremes using two sets of climate model simulations under a high‐CO2 scenario. In one set of simulations, SO2 is injected into the stratosphere at the equator to stabilize global mean warming at the present‐day level; in another set of simulations, SO2 is injected into the stratosphere at four different latitudes to stabilize global mean temperature, interhemispheric temperature gradient, and equator‐to‐pole temperature gradient at the same time. Our analysis shows that both equatorial injection and multi‐location injection can help reduce temperature and precipitation extreme events induced by global warming, but their effectiveness varies across different regions. In general, compared to equatorial injection, multi‐location injection can be more effective in stabilizing climate extremes at the present‐day level over most regions. This is consistent with the fact that multi‐location injection exhibits smaller changes in mean climate state than that of the equatorial injection relative to the present‐day state. Key Points: We examine the climate extreme response to two stratospheric aerosol injection (SAI) strategies: equatorial injection and multi‐location injectionThe response of climate extremes to SAI shows similar characteristics to mean climate responseMulti‐location injection is more effective in stabilizing climate extremes at the present‐day level [ABSTRACT FROM AUTHOR]

Existing estimates of the climate mitigation potential from cropland carbon sequestration (C‐sequestration) are limited because they tend to assume constant rates of soil organic carbon change over all available cropland area, use relatively coarse land delineations, and often fail to adequately consider the agronomic and socioeconomic dimensions of agricultural land use. This results in an inflated estimate of the C‐sequestration potential. We address this gap by defining a more appropriate land base for cover cropping in the United States for C‐sequestration purposes: stable croplands in annual production systems that can integrate cover cropping without irrigation. Our baseline estimate of this suitable stable cropland area is 32% of current U.S. cropland extent. Even an alternative, less restrictive definition of stability results in a large reduction in area (44% of current U.S. croplands). Focusing cover crop implementation to this constrained land base would increase durability of associated C‐sequestration and limit soil carbon loss from land conversion to qualify for carbon‐specific incentives. Applying spatially‐variable C‐sequestration rates from the literature to our baseline area yields a technical potential of 19.4 Tg CO2e yr−1 annually, about one‐fifth of previous estimates. We also find the cost of realizing about half (10 Tg CO2e yr−1) of this potential could exceed 100 USD Mg CO2e−1, an order of magnitude higher than previously thought. While our economic analyses suggest that financial incentives are necessary for large‐scale adoption of cover cropping in the U.S., they also imply any C‐sequestration realized under such incentives is likely to be additional. Plain Language Summary: As a "Nature‐based Climate Solution" (NCS), the practice of cover cropping has received widespread attention and investment recently. Through cover cropping, croplands may be able to absorb and hold more carbon in soil, drawing down CO2 in the atmosphere (i.e., sequester carbon). However, the sequestration that is feasible, which reflects socioeconomic and land use considerations, remains unquantified. We estimate this feasible potential for carbon sequestration in the U.S. croplands from cover cropping and find it to be a fraction of previous estimates. A large portion of the reduction is due to our use of a more realistic and rigorous definition of the land area suitable for cover cropping for climate mitigation purposes. This land area comprises "croplands remaining croplands" (or stable croplands) that are planted to annual crops, like corn and soybeans, because they can more easily integrate the practice. We exclude irrigated croplands to conserve water resources. At just under 44 million ha, our baseline area estimate is 32% of the current U.S. cropland extent. The rest of the reduction is associated with our use of more conservative rates of increase in soil carbon from cover cropping than earlier studies that are more realistic for assessing soil carbon sequestration potential over large areas. Our economic analyses suggests that without financial incentives, implementing cover cropping could be expensive for most U.S. farmers. This high cost hurdle needs to be evaluated against the cost‐effectiveness of alternatives that compete for the same limited resources for climate mitigation. Key Points: For U.S. croplands, the feasible potential of carbon sequestration from cover cropping is a fraction of previous estimatesDefining the land base suitable for mitigation practices more realistically and rigorously is critical to estimating the feasible potentialCover cropping, though beneficial for soil health, may not be a low‐cost pathway for climate mitigation at scale in the U.S. [ABSTRACT FROM AUTHOR]

Trade‐off conflicts among the Sustainable Development Goals have been a challenge. To reconcile frictional relationships among food production security (Goal 2), water use efficiency (Goal 6), and climate change mitigation (Goal 13), an empirical examination using deterministic frontier analysis was conducted globally. A single volume‐based index for each goal is too simple to evaluate the agricultural sustainability of different areas from the nexus assessment perspective. Our major findings are threefold. First, approximately two‐thirds of African countries have suffered from small food production and excess water use. Second, marked contrasts are observed in the possibilities of an increase in food production and reduction in water use and CO2 emissions among regions. Asian countries use water efficiently, whereas countries in the western regions control CO2 emissions. Third, trade‐offs among food production, water use, and CO2 emissions in agriculture are observed. It is almost impossible to reduce water use in Asia and CO2 emissions in the western regions for food production security. Based on the nexus approach, local strategies need to be compatible with global sustainability. Future research should identify the factors that determine the agricultural efficiency to devise local strategies, and develop policies simultaneously pursuing relevant environmental and well‐being goals. [ABSTRACT FROM AUTHOR]