The Atlantic Meridional Overturning Circulation (AMOC), a key component of the global climate system, behaves as a typical climate tipping element with multi-stable states. Changes in AMOC instigate a series of cascading effects, profoundly affecting distributions of heat and moisture globally. Up till now, due to relatively short durations of direct observations from monitoring arrays (e.g., RAPID array (21 years) and OSNAP array (11 years)), our understanding of the evolution of the AMOC since the mid-20th century remains highly controversial. Fingerprint reconstructions based on sea-surface temperature and salinity proxies show a marked AMOC weakening since the mid-to-late 20th century, whereas estimates derived from the impacts of circulation intensity changes as well as those based on physical principles—such as ocean-atmosphere heat fluxes or sea surface height gradients—mostly show no significant trend. Additionally, although some metrics may also be able to characterize the AMOC variability, they are generally difficult to robustly assess the long-term trends due to data limitations (e.g., resolution of sedimentary records and measurement uncertainties) and specific processing methods (e.g., the detrending applied to sea-level gradient indices). These discrepancies underscore the inherent limitations of different reconstruction methods, and/or the potential masking effects of the natural variability.

Regarding future changes in the AMOC, while multi-model ensembles project with high confidence that the AMOC will weaken persistently over the rest of 21st century, the degree of this weakening remains highly uncertain. Furthermore, substantial discrepancies are apparent among different models: although some modeling studies indicate the theoretical existence of a future AMOC tipping point, the timing of such an event in the real climate system remains extremely uncertain. On the other hand, potential negative feedback mechanisms in the climate system could have a stabilizing effect on the AMOC, but this is difficult to assess assuredly. Overall, the most plausible scenario for the future AMOC evolution would be a continued weakening trend, accompanied by an unquantifiable yet non-negligible risk of abrupt transition. To address the knowledge gaps that are critical in the field, such as the outstanding issues concerning potential false positives in early warning signals, the model biases in simulating modern climate processes, and projection biases caused by the missing of key processes including ice-sheet melting, future research should focus on the following priorities. (1) Expand direct observation arrays to enhance the spatiotemporal coverage. (2) Improve climate models, particularly by incorporating ice-sheet processes, to enhance the ability to simulate abrupt climate transitions. (3) Integrate Bayesian statistical frameworks to explicitly incorporate the prior probability for the existence of tipping points and to quantify the risk of abrupt transition through likelihood ratio analysis. (4) Promote research on “past-present analog” in the early warning analysis to understand modern signals in the context of paleoclimate resemblances, thereby improving prediction reliability. (5) Deepen our understanding of the cascades in response to changes in AMOC by reconstructing high-resolution geological records from key regions beyond the North Atlantic, thus providing more evidence for assessing the stability of the climate system. This represents a novel approach to infer AMOC stability through cascading responses to AMOC changes from other climate systems. However, caution is usually required for such an approach, as the coupling could potentially undermine the reliability of early warning signals. (6) Improve machine learning approaches to identify complex nonlinear patterns and early warning signals of AMOC stability from multi-source data, thereby helping to distinguish true critical slowdowns from data-artifact “false positives”, predicting rate-induced tipping points under noisy conditions, and identifying underlying physical drivers. These efforts are crucial for reducing uncertainties in future AMOC projections—a vital part of global climate risk assessment.

In recent years, the Qilian Mountains region has experienced frequent heavy precipitation events, resulting in significant casualties and property damage. However, the physical mechanisms behind the frequent occurrence of heavy precipitation remain unclear. Based on rainfall station observations in the Qilian Mountains region from 1961 to 2023 and NCAR/NCEP reanalysis data, this paper investigates the interdecadal variation characteristics of summer heavy precipitation in the study area and its causes. The results indicate that (1) over the past 63 years, there were 555 heavy precipitation days during summer in the Qilian Mountains region, primarily distributed in the exorheic river valleys of the southeastern part. Both the number of heavy precipitation days and the total heavy precipitation amount increased significantly after an abrupt change in 1992. A survey of weather maps on heavy precipitation days revealed a notable increase in heavy precipitation days associated with Tibetan Plateau Vortices (TPVs). (2) On heavy precipitation days in the Qilian Mountains region, the tropospheric atmosphere over Eurasia exhibited an anomalous wave train pattern, resembling the Silk Road Pattern (SRP). The southerly winds on the eastern side of the anomalous cyclone near the Qilian Mountains enhanced the transport of warm and moist airflow to the northeastern Tibetan Plateau, which tends to facilitate the formation and development of the TPV and the occurrence of heavy precipitation. (3) After 1992, the SRP index underwent an interdecadal shift from a negative to a positive phase, leading to a significant increase in the meridional moisture flux transported to the northeastern Tibetan Plateau. These factors collectively contributed to the increased activity of TPVs, which in turn became the main mechanism driving the interdecadal increase in summer heavy precipitation in the Qilian Mountains region.

The voluntary carbon market (VCM), which incentivizes organizations and individuals to take emission reduction actions through market mechanisms, serves as a critical policy tool for achieving the temperature goals of the Paris Agreement. However, the current VCM faces severe challenges in terms of environmental integrity and sustainable development benefits. A series of solutions have been proposed by different stakeholders to promote the development of high-quality VCM. This paper systematically reviews the key issues undermining the quality of VCM, compares major measures proposed to address these issues, and evaluates their respective advantages and disadvantages. Based on the characteristics and current status of China’s voluntary carbon market, this paper proposes insights and recommendations for promoting the development of a high-quality VCM in China.

Mitigating coal mine methane, China’s largest source of methane emissions, is a key measure for synergistically advancing climate governance, energy security, and economic transition. This is particularly critical as the country strengthens its management of all greenhouse gases, including methane, under its new Nationally Determined Contributions (NDCs). Currently, China has developed a multi-layered incentive policy framework incorporating financial subsidies, tax incentives, and carbon market mechanisms, which has fostered consistent growth in methane extraction and utilization. Nevertheless, significant challenges remain, such as the low cost-effectiveness of utilizing low-concentration methane, inadequate targeting of subsidy policies, the lack of a robust monitoring, reporting, and verification (MRV) system, and fragmented interagency governance. To tackle these issues, this paper conducts a systematic review of policy approaches adopted by the United States, Australia, Europe Union, and other relevant countries. From this analysis, several key insights emerge: regulatory mandates and compliance form the policy foundation; economic incentives must be precise and differentiated; fiscal funding serves as a catalyst; market-based mechanisms drive long-term mitigation; and policy packages should be tailored to local contexts. Informed by these findings, the paper proposes a comprehensive policy optimization framework built on four pillars: targeted incentives, systemic support, market-driven mechanisms, and coordinated governance. Concrete recommendations include introducing subsidy tiers based on methane concentration and differentiated electricity pricing, setting up dedicated innovation funds, enhancing carbon market design while piloting subnational carbon inclusion mechanisms, and establishing integrated MRV and cross-departmental coordination systems. Ultimately, this study aims to offer systematic guidance for transitioning China’s coal mine methane mitigation efforts from a resource utilization-focused model toward a strategy oriented around precise emission control.

The animal husbandry sector is a pivotal area for achieving China’s food security and dual carbon goals (carbon peak and carbon neutrality). The control of methane (CH₄) emissions from this sector holds profound implications for the self-sufficiency rate of livestock products, the optimization of dietary patterns, and the response to climate change. This paper systematically analyzes the current status of CH₄ emissions from the livestock sector, emission reduction technologies, as well as the gaps and needs in CH₄ mitigation technologies across the top ten global CH₄ emitting countries and regions (six Annex I countries and regions and four non-Annex I countries). From 1990 to the latest reporting year, the growth in livestock CH₄ emissions in major emitting countries has been primarily driven by non-Annex I Parties (e.g., China and Brazil), closely linked to dietary transitions and the expansion of livestock farming scales. In contrast, Annex I Parties (e.g., the United States and the European Union) have reached a plateau or shown a declining trend. China has relatively low per capita emissions. With the increase in China’s livestock production, CH₄ emissions from both enteric fermentation and manure management have shown an upward trend. Facing challenges related to the sustainable development of animal husbandry, climate change mitigation, and international climate diplomacy, CH₄ reduction necessitates a comprehensive consideration of multiple factors, including genetic breeding, feed regulation, manure treatment, and resource utilization. Furthermore, integrating policy standards with optimized emission reduction technologies is essential to establish a full-chain management and control technology system. This approach will facilitate the low-carbon and efficient transformation of the animal husbandry sector, balancing stable supply with emission reduction goals to achieve green and high-quality development in the sector.

This study proposes a novel integrated dynamic CGE-LCA framework to evaluate the economy-wide, social, and environmental impacts of producing sustainable aviation fuel (SAF) from agricultural residues through the Fischer-Tropsch (FT) synthesis pathway in China. Unlike conventional assessments that rely on static life-cycle analysis or partial-equilibrium approaches, the proposed framework endogenously links FT fuel technology learning, blending mandates, cost pass-through mechanisms, and sectoral interactions within a dynamic general equilibrium setting, enabling a consistent simulation of FT industry development from 2025 to 2040. Scenario-based simulations indicate that aviation mitigation costs are highly sensitive to FT fuel prices. Under a technology stagnation scenario (S₁), mandatory FT blending results in an average annual abatement cost of 132.4 billion CNY, whereas under a cost-parity scenario with conventional jet fuel (S₃), mitigation costs decline by 77.7%. Incorporating demand responses reveals that transferring additional fuel costs to passengers leads to a measurable contraction in air travel demand, highlighting the importance of demand-side feedbacks often omitted in existing studies. The model further captures the macroeconomic spillover effects of FT industry expansion. Under the S₃-Q₃ scenario, China’s GDP increases by 0.96% and the employment rate rises by 0.99% by 2040, while large-scale utilization of agricultural residues raises farmers’ income by up to 277.0 billion CNY. From an environmental perspective, when the FT blending ratio reaches 47% in 2040, cumulative CO₂ emissions from civil aviation are reduced by 23.9% relative to the baseline scenario. By embedding process-based life-cycle emission coefficients into the CGE production structure, the framework identifies the production stage as the dominant source of FT fuel life-cycle emissions, accounting for 65.3% of total CO₂ emissions. Although FT deployment increases emissions in energy supply and other transport sectors, the net mitigation effect remains positive due to larger emission reductions in agriculture and civil aviation. Overall, the proposed CGE-LCA framework provides a transferable and policy-relevant tool for assessing large-scale SAF deployment and supports the formulation of strategies for the high-quality development of China’s biomass-based aviation fuel industry.

Global temperature control goals require constraining anthropogenic carbon emissions within a limited carbon budget, where different allocation schemes significantly influence national emission constraints and varying pathway strategies profoundly impact energy transition processes. China’s carbon neutrality commitment necessitates unprecedented energy system transformation within three decades, making comprehensive assessment of pathway impacts under global carbon budgets critically important. This study developed 24 carbon-neutral energy transition scenarios combining carbon budget allocation schemes with pathway strategies, utilizing the Global Change Analysis Model (GCAM) to analyze impacts on primary energy consumption, end-use electrification, power structure transformation, and carbon pricing. Results demonstrate that under 1.5℃ target, China’s carbon budget remains severely constrained at 103.4-141.3 Gt CO₂, while 2℃ target permits larger budget of 239.7-329.4 Gt CO₂, with equity-based principles imposing more stringent constraints than grandfathering principles due to historical emission considerations. The choice of emission reduction pathways will profoundly shape the trajectory of China’s energy transition. Under 1.5℃ target, an emission reduction strategy characterized by initial delay followed by accelerated action (“delayed-action”) would substantially increase reliance on CO₂ removal technologies. Conversely, “rapid-then-slow” and “intermediate pathways” will effectively avoid potential increases in social costs. Specifically, within the 1.5℃ target, the average carbon price by 2060 under the “delayed-action” pathway is projected to be 56% to 89% higher than under the “rapid-then-slow” and “intermediate pathways”. This persists at 9%-21% even under 2℃ target. Furthermore, the new Nationally Determined Contribution (NDC) target for China to exceed 30% non-fossil energy consumption by 2035 will surpass most 2℃ target scenarios. Among these, the non-fossil energy consumption in the “rapid-then-slow” and “intermediate pathway” scenarios for 2035 is closer to China’s new NDC target.

Under climate change, rice production faces the dual challenges of sustaining yield stability and reducing greenhouse gas emissions. Achieving yield stability under climate change without exacerbating emissions has therefore become a central challenge for sustainable rice systems. This review synthesizes recent advances in understanding how climate change influences rice physiological and ecological processes, as well as yield and quality formation. We further consolidate current knowledge on methane (CH₄) and nitrous oxide (N₂O) emissions from paddy fields, highlighting their biogeochemical mechanisms, temporal dynamics, and the critical regulatory roles of water management, nitrogen inputs, and organic carbon availability. Building on these mechanistic insights, we systematically evaluate major adaptation and mitigation strategies, including stress-tolerant and low-emission varietal improvement, optimized irrigation regimes (e.g., alternate wetting and drying with risk-sensitive thresholds), precision nutrient management and enhanced-efficiency fertilizers, cropping system optimization (such as ratoon rice and diversified rotations), and straw management through incorporation, partial removal, or biochar conversion. Comparative analysis indicates that efficiency-enhancing practices, particularly coordinated water-nitrogen management, ratoon-based systems, and digital decision-support tools, often generate synergistic benefits for both yield stability and emission reduction. In contrast, several widely adopted practices exhibit strong context dependency and may involve trade-offs, most notably CH₄-N₂O substitution under intermittent irrigation and increased CH₄ emissions following straw return under prolonged flooding. We identify critical constraints limiting large-scale implementation, including regional heterogeneity in infrastructure and management capacity, uncertainties under compound climate extremes, insufficient long-term evidence linking productivity, grain quality, and emissions, high monitoring and verification costs, and weak economic incentives for farmers. Future research priorities include establishing long-term, multi-site experimental networks across major rice-producing regions, strengthening the coupling of field observations with process-based modeling for robust scenario assessment, and developing multi-dimensional assessment frameworks that integrate yield stability, grain quality, greenhouse gas emissions, resource-use efficiency, and farm-level economic resilience. Coordinated policy instruments that integrate irrigation governance, extension services, risk sharing mechanisms, and credible monitoring, reporting and verification systems will be essential to accelerate the transition toward climate resilient, high yielding, and low-carbon rice production systems.

Against the backdrop of China’s “Carbon Peaking and Carbon Neutrality” goals, blue carbon ecosystems—such as mangroves, coastal salt marshes, and seagrass meadows—have garnered increasing attention as critical natural carbon sinks. However, institutional barriers related to the definition, confirmation, and registration of carbon sequestration property rights continue to hinder the development of blue carbon trading projects in China. This paper systematically reviews the current status and key challenges of property rights clarification mechanisms in China’s blue carbon initiatives. It further synthesizes international practices in the allocation of carbon rights within blue carbon projects and explores the specific difficulties associated with attributing carbon sink rights across the three major ecosystem types. Through a comparative analysis of international case studies, the research finds that China’s blue carbon property rights framework remains at an exploratory stage, with relevant legal and regulatory systems yet to be fully developed. Overlapping administrative responsibilities across sectors (including natural resources, ecological environment, forestry, and marine affairs) have led to significant coordination challenges. Moreover, the ownership and benefit entitlement to carbon revenues derived from natural resources, such as mangroves, remain unclear, with management entities often lacking autonomous control over carbon-related income. To address these issues, this paper recommends establishing a standardized and unified property rights registration system for blue carbon ecosystems, improving incentive mechanisms, and enhancing regulatory enforcement. These measures aim to clarify carbon sink ownership, improve the efficiency of market-based carbon trading, and support ecosystem restoration and value realization. The findings provide policy insights to advance China’s climate actions and ecological civilization goals.

As the tenth anniversary of the Paris Agreement, global climate governance has shifted from ‘commitment to targets’ to ‘implementation of actions’. Systematic evaluation of national climate progress is essential for achieving the Agreement’s targets. This study uses 217 indicators from 198 countries and regions to build a comprehensive assessment framework covering target, policy, action, and effectiveness. The results show that, between 2024 and 2025, the global carbon neutrality process is characterized by steady progress in target and policy, stagnation in action, and limited effectiveness in emission reductions. Progress in target and policy reflects a continued global trend toward green transformation, despite fluctuations in some countries. The lack of visible emission reductions is mainly due to insufficient policy enforcement and delays in technological implementation. Based on target and effectiveness performance, countries are grouped into four groups: climate leaders, low-key achievers, transition challengers and emerging players. In 2025, 92 countries shifted between these groups, showing pronounced dynamics. This study provides insights into the differences and changes in national approaches to climate goals, policy, and technology, contributing to global climate governance.

Achieving carbon neutrality is fundamentally a systemic transformation centered on the restructuring of energy systems. Single-discipline and individual technological pathways are insufficient to address the complex system constraints in the energy transition. This paper identifies the cross-disciplinary bottlenecks in energy system restructuring through literature review and case analysis, including the high cost and energy consumption of carbon capture technologies in industrial production, insufficient regulation capabilities under high shares of renewable energy integration, and the lack of synergy between pollution control and carbon reduction goals. Based on these challenges, four frontier directions for cross-disciplinary integration supporting energy system restructuring are proposed: the zero-carbon technology system driven by the intersection of energy and materials, the smart regulation system for new power grids through energy-environment integration, the synergistic pollution control and carbon reduction technology system, and the carbon-neutral pathway decision support system based on the coupling of energy, materials, and the environment. Finally, combining technological maturity and system integration conditions, stage-wise deployment and mid-to-long-term strategic recommendations are presented, aligned with the next round of Nationally Determined Contributions (NDCs) and the long-term carbon neutrality vision, to provide a systematic reference for constructing a clean, low-carbon, safe, and efficient new energy system.

Meteorological departments, serving as the core supporting departments in addressing climate change, play an irreplaceable, fundamental, pioneering, and systemic role throughout the entire chain of climate change monitoring, assessment, early warning, adaptation, accounting, economic transformation, and international negotiations. This article analyzes the characteristics of the national climate change adaptation system from the perspectives of its objectives and organizational structure. It elaborates on the eight key responsibilities of meteorological departments, which include: foundational monitoring and data provision for climate change; detection, attribution, and scientific assessment of climate change; climate prediction and risk management of extreme events; impact assessment of climate change and support for adaptation decision-making; greenhouse gas accounting and carbon emission assessment; detailed investigation of wind and solar energy resources and support for clean energy dispatch; economic transformation of climate resources and integrated innovation of “Meteorology Plus” services; and science popularization on climate change and support for international negotiations. Finally, the article proposes countermeasures and suggestions in five areas: adhering to the principle of fulfilling one’s duties and taking proactive action to enhance the role of meteorological departments within the national climate change adaptation work system; adhering to the principle of prioritizing key areas while ensuring overall coordination to effectively implement adaptation tasks in critical sectors and regions; adhering to the principles of initiative, interaction, and collaboration to foster a favorable situation where multiple parties jointly advance climate change adaptation work; adhering to the principle of innovation-driven development and strengthening foundational capacities to rapidly enhance the meteorological departments’ own capabilities in climate change adaptation; and adhering to the principle of engaging globally and leveraging strengths to contribute Chinese meteorological wisdom, solutions, and contributions to global climate change adaptation efforts.