Climate extremes threaten human health, economic stability, and the safety of both natural and built environments. Compound extreme events are combinations of multiple climate drivers and/or hazards that contribute to societal or environmental risks, and their impacts on human society and natural ecosystems are often more serious and destructive than those of a single extreme event. Understanding the changes in compound extreme events is important for adaptation, mitigation strategies, and disaster risk management. Here, the definitions and connotations of compound extreme events are briefly discussed, including preconditioned, multivariate, temporal, and spatial compounding events. Subsequently, the progress in compound extreme event research is discussed in terms of temporal and spatial evolution characteristics, influencing factors, and future scenario projections. Given the problems in current research, we suggest that future studies should focus on studying compound extreme events regarding variable/index selection and threshold determination, dependence and interaction analysis among drivers and/or hazards, simulation performance evaluation and future projections, and their dynamic processes and disaster-causing mechanisms. Compound extreme events are expected to increase in frequency and intensity in a warming world, and many regions are projected to experience an increase in the probability of compound events with greater global warming. Therefore, we must improve our understanding of the causes and drivers of compound and cascade events.

At around 20 km height in the atmosphere, a natural phenomenon occurs, in which the lower westerly (easterly) zonal wind changes into the upper easterly (westerly) zonal wind during a specific season, while the meridional wind is very small. This transition layer of the zonal wind is called stratospheric Quasi-Zero Wind Layer (QZWL). The low speed and direction transition of the wind in the QZWL are beneficial for stratospheric airships, high-altitude balloons, and other weakly powered or unpowered near-space vehicles, allowing them to stay there for longer periods. The characteristics of the QZWL with time in the northern hemisphere, the entire China, and key regions in China were summarized based on the QZWL results. The influence mechanisms and characteristics of the thermal wind, stratospheric Quasi-Biennial Oscillation (QBO), Stratospheric Sudden Warming (SSW), eddy flux transport of planetary wave, South Asia high and subtropical westerly jet on the QZWL formation were systematically analyzed. The advantages and disadvantages of MST radar, laser radar, sounding rocket and upper-air balloon in QZWL detection and some relevant facts were compared and analyzed. The advantages and disadvantages of middle atmosphere modeling and numerical weather modeling regarding QZWL forecasting were summarized. Numerical weather modeling is currently the main method for QZWL forecasting and meteorological support, and diagnostic schemes, such as the bottom height and thickness of the QZWL, are the basis for the quantitative study of the refined structure and evolution of the QZWL. The working principle of stratospheric vehicles using the QZWL is summarized. Finally, prospects regarding the key directions of future scientific research are presented. This review of the research progress on the QZWL will provide the basis for the future in-depth study of the QZWL and the deployment and meteorological support of stratospheric vehicles.

The Diurnal Cycle of Precipitation (DCP) is the result of various dynamic and thermodynamic processes in the climate system and is closely related to the water cycle and land-atmosphere interactions. In North China, the DCP is influenced by factors such as valley wind circulation, boundary layer inertial oscillations, and sea-land breeze circulation, exhibiting two peaks during the early morning and afternoon. In addition, the DCP in North China is influenced by anthropogenic aerosol emissions. This study introduces the fundamental characteristics and factors influencing the DCP in North China and summarizes recent research on the connection between the DCP and land-atmosphere coupling in North China, the modeling of the DCP, and the influence of aerosols on the DCP. The existing scientific knowledge is synthesized, and its shortcomings and challenges are outlined. Overall, investigating the DCP and its influencing factors can help us better understand the mechanisms of precipitation formation and evolution. This provides scientific support for enhancing the accuracy of fine-scale precipitation forecasting.

Evapotranspiration (ET) encompasses water loss through transpiration and evaporation from soil and water surfaces. Accurate observation of ET is essential for comprehending the ET process, and mechanism, as well as water-energy nexus and land-atmosphere feedback. ET serves as a pivotal link between the hydrological cycle and energy processes. In-situ measurements provide fundamental datasets for validating remotely sensed ET products. The surface renewal theory differs from the commonly used eddy covariance method in describing the physical ET process. Unlike the expensive sonic anemometers in the eddy covariance system, the surface renewal method is cost-effective because it uses a fine- diameter thermocouple to record high-frequency air temperature and estimate the sensible heat flux through coherent structures. The surface renewal method for measuring ET, with an accuracy comparable to that of the eddy covariance system, and it has been widely applied for ET measurements in America and Europe. Recognizing the substantial potential of this method, this paper reviews the theory of surface renewal and research advancements in the method made over the past 30 years. Additionally, preliminary studies related to ET measurements in China using the surface renewal method are also presented. By summarizing this progress and exploring the challenges in the application of the surface renewal method, we can enhance our understanding and promote a variety of domestic ET observation methods.

Guizhou Province, characterized by unique topography and complex climatic conditions, offers an excellent opportunity to study spectral surface albedo (short-wave, near-infrared, and visible light). Analyzing this refines surface parameters and understands the characteristics of solar spectral radiation but also provides scientific references to explore the physical processes of the relevant spectral radiation, variables in the process of energy conversion of the earth-air system in mountainous areas at low latitudes. Therefore, based on MCD43A3 albedo data, MCD15A2H Leaf Area Index (LAI), temperature, precipitation, land use, and soil moisture data, using anomalous variance analysis, Theil-Sen (T-S) and Mann-Kendall (M-K) trend analyses, and geophones, we analyzed the spatial and temporal trends and driving factors of spectral surface albedo in Guizhou Province. The results show that \mathrm{①} interannual changes in spectral surface albedo were in the order of size: near-infrared>short-wave>visible. In addition to visible surface albedo being on the rise (the three bands of surface albedo high-value area were basically the same), there was a line from the northeast to the southwest, and the western distribution of the characteristics of the County of Weining; \mathrm{②} considering seasonal changes, the size order of short-wave and near-infrared surface albedo was the same, as follows: summer>autumn>spring>winter and that of visible surface albedo was spring>winter. The sizes of short-wave and short-wave albedo were the same, as follows: summer> autumn>spring>winter, and that of visible surface albedo was: spring>winter>autumn>summer; \mathrm{③} the driving factors of spectral surface albedo were LAI, followed by land use. The results of this study reveal spatial and temporal variations and driving mechanisms of the spectral surface albedo in Guizhou, which can provide a reference for the ecological protection of mountainous areas in Guizhou.

Ecological resilience, the ability of an ecosystem to absorb and adapt to environmental change to maintain its sustainability, was first systematically introduced by the Canadian ecologist C.S. Holling in 1973 and has since rapidly attracted attention and been used across multiple disciplines. In the context of global change, the response of terrestrial ecosystems to increasingly intensifying arid environments, specifically the spatial patterns and evolutionary mechanisms of vegetation ecological resilience under drought stress, has become a core focus of current ecological and ecohydrological research. In recent years, numerous studies have been conducted on the relationship between vegetation change and water stress, enhancing our understanding of this mechanism. However, the interpretation of the ecological resilience of vegetation varies widely and remains controversial, and one of the main reasons for this is that the understanding of the connotations of ecological resilience is not yet unified. To address this issue, we synthesized the views of researchers worldwide and suggested that the analysis of ecological resilience should not only consider the system resistance and recovery capacity under drought events but also the system response and adaptation behavior under changing environments from the perspective of system evolution. These include resistance, recovery, and adaptation, which should be the three most important dimensions for determining ecological resilience. Focusing on these three main dimensions, we reviewed the results of recent research conducted globally and summarized the current understanding of ecological resilience and the key issues to be addressed in terms of spatial patterns, impact mechanisms, and adaptation strategies for ecological resilience. Through an analysis of the concept of ecological resilience and the current state of research, we hope to promote academic discussions on the definition of ecological resilience and its quantitative methods to facilitate an understanding of the evolution of resilience and its underlying mechanisms.

The value realization of ecological products is not only the practice of the concept of “green mountains and clear waters are gold and silver mountains”, but also an important channel to solve the contradiction between China’s social and economic development and ecological environmental protection, which is of great significance to comprehensively promote China’s economic green transformation. Through a systematic review of the existing scholars’ research on the realization of the value of ecological products, it is shown that: \mathrm{①} The number of studies related to ecological products has increased significantly, and the research content has become more in-depth, which effectively promotes the development of interdisciplinary integration. \mathrm{②} The research content involves the concept discrimination, connotation, and extension of ecological products, the accounting method of ecological product value, the path and mode of ecological product value realization, the practical exploration and typical case analysis of ecological product value realization, and the construction of an institutional guarantee of value realization, etc. This suggests that there may be difficulties in the process of realizing the value of ecological products and ensuring the efficient transformation of the value of ecological products remains a challenge for future research. Through sorting theoretical research and the summary and analysis of typical practice exploration cases, it is expected to provide certain references for the transformation from “clear waters and green mountains” to “gold and silver mountains”.

The National Natural Science Foundation of China (NSFC) has received widespread attention as the primary funding institution for basic scientific research in China. Here, we analyze the results of the proposals received by the Division of Geography, Department of Earth Sciences, National Natural Science Foundation of China, in 2023. An analysis of the proposal review and funding processes was undertaken for three sub-disciplines (Physical Geography, Human Geography and Geographic Informatics); three types of projects (general program, Young Scientists Funding Program, and Regional Funding Project); and four scientific themes or focus areas, as formulated by the NSFC. In addition, issues to be noted in the proposal submission and peer review are discussed. For projects completed by the end of 2022, we first analyzed the publication status of SCI/SSCI/EI/CSCD/CSSCI indexed articles in various project categories and then focused on the representative achievements.

We analyzed the submissions, acceptances, reviews, and grant funding of various projects managed by the Environmental Geosciences Division，National Natural Science Foundation of China in 2023, and we summarized the outcomes of funded and completed projects of this discipline at the end of 2022. Based on this analysis, the advances in environmental geosciences are discussed.

Ozone is among the most important trace gases in Earth’s atmosphere and plays a crucial role in both climate change and ecology. Tropospheric ozone is an important component of photochemical smog, and its variations are closely related to human activity. Monitoring of tropospheric ozone based on satellite remote sensing can help us better understand and quantitatively explain the characteristics of tropospheric ozone changes in different seasons, times, and regions, and explore the mechanism of ozone generation in the troposphere. With the comprehensive development of satellite remote sensing techniques, ozone remote sensing products (e.g., total ozone, profiles, etc.) have improved significantly in terms of accuracy and spatiotemporal resolution. However, the accuracy of tropospheric ozone products is still not sufficient for the current scientific application of the atmospheric composition of the troposphere due to the weak satellite signals and complexity of the subsurface. This review focuses on satellite remote sensing of tropospheric ozone. It outlines and analyzes the development history and current status of ozone satellite remote sensing payloads and discusses the characteristics and applicability of remote sensing retrieval algorithms based on different technologies (direct and indirect retrieval, multiband joint retrieval, collaborated nadir-limb retrieval, and innovative algorithms based on machine learning techniques). It further discusses the application of satellite remote sensing for the provision of reliable tropospheric ozone observation data at the global and regional scales. Overall, this review envisions the application of satellite remote sensing for providing reliable tropospheric ozone observations at the global and regional scales.

Hydrological and water resource monitoring are pivotal components of Earth observation systems, crucial for supporting the high-quality development of water conservancy in the modern era, fulfilling the requirements of “three water” co-governance, and implementing the “sixteen words” water-control strategy. Satellite remote sensing offers a scalable, rapid, and high-precision data acquisition pathway. Nonetheless, challenges persist in the application of existing satellite remote sensing in hydrology and water resources, including difficulties in achieving multi-satellite synchronous observation, limited emergency response capability, and susceptibility to adverse weather conditions. In December 2022, NASA launched the Surface Water and Ocean Topography (SWOT) satellite, the first satellite in the world designed to observe global land and ocean water resources through multisensor collaboration. This groundbreaking satellite greatly improves the spatial and temporal resolution and accuracy of hydrology and water resource monitoring. This study systematically reviews the development status, applications, and technical challenges of hydrological and water resource monitoring satellites. It also analyzes the satellite parameters, scientific tasks, algorithm flow, and application products of SWOT, providing a valuable reference for future satellite design planning and key data processing technologies, especially in China.

On August 24, 2023, the Japanese government started discharging the Fukushima Nuclear Contaminated Water (FNCW) into the North Pacific. This process is bound to pose radiation risks for the marine ecological environment. In this study, we analyzed the concentrations of major artificial radionuclides in the FNCW and estimated their inventories. Based on the data provided by the Tokyo Electric Power Company, we found that the concentrations of ³H in FNCW tanks as of March 2023 ranged from 1.9×10⁵ to 25.0×10⁵ Bq/L, significantly exceeding the maximum release concentration for ³H (6×10⁴ Bq/L) allowed by Japanese law. In addition, the concentrations of ⁹⁰Sr and ¹²⁹I in some FNCW tanks were higher than the corresponding maximum release concentrations (30 Bq/L for ⁹⁰Sr and 9 Bq/L for ¹²⁹I) allowed by Japanese law. The inventories of ³H and ¹²⁹I in the FNCW before the discharge were estimated to be 0.9 and 6.2×10⁹ Bq, respectively, i.e., comparable to the leakage amounts of ³H (0.1~1.0 PBq) and ¹²⁹I (6.9×10⁹ Bq) to the ocean during the nuclear accident stage. We further discuss the migration and behavior of typical Fukushima radionuclides (e.g., ³H, ¹⁴C, ⁶⁰Co, ⁹⁰Sr, ¹²⁹I, ^{134, 137}Cs, and ^{239, 240}Pu) in marine environments from three aspects: \mathrm{①} transport of Fukushima radionuclides by ocean currents in the Pacific; \mathrm{②} sediment adsorption to radionuclides; and \mathrm{③} marine biota uptake of radionuclides. This study is expected to provide scientific foundations and insights for radiation monitoring and risk assessment, which may be required for an appropriate response to the discharge of the FNCW.

The Yangtze River is the largest river system in Asia, and its formation and evolution are of great significance for understanding the topography, climate change, biological evolution, and material cycles of East Asia. The Three Gorges lie in the central Yangtze Block, and its formation connects the drainage in the Sichuan Basin and the Jianghan Basin; therefore, it is regarded as one of the most critical events in the history of the Yangtze River. However, the debate over how and when the Three Gorges were formed has been ongoing for over a century. This study reviews the century-long debate, especially regarding the formation mechanism and age of the Three Gorges, to clarify the formation of the Yangtze Three Gorges. A comparison highlighted a conflict between the erosion time of the Three Gorges and the provenance analysis in the downstream basin, stemming from limitations in research ideas, objects, and methods. Determining the formation time of the Three Gorges necessitates a comprehensive approach that integrates gorge erosion and provenance analysis in the Jianghan Basin. Methods such as monazite fission track, cosmogenic nuclide dating, and geochemical analysis of single-grain minerals offer precise constraints on gorge erosion and aid in establishing a source-sink system between the Jianghan Basin and Sichuan Basin. Drawing on the principles of Earth system science and source-sink systems, this study proposes an analysis of tectonics, landforms, and climatic evolution to understand the evolution of large drainage systems such as the Yangtze River. In particular, a comprehensive analysis of the geochemical characteristics and exhumation histories of the Qinghai-Xizang Plateau, basin development, and geochemical characteristics of detritus minerals is required to investigate the evolutionary processes of large rivers such as the Yangtze River.

Rivers connect the terrestrial landscape and oceans and are considered “bioreactors” of carbon. Understanding the carbon cycling processes in rivers and constructing numerical models for riverine carbon cycling is imperative to estimate regional and global carbon budgets. The summary and discussion of the development and application of riverine carbon cycling models remains inadequate. This study reviewed the mechanisms and models of riverine carbon cycling based on a comprehensive literature review. First, we briefly overview the critical processes in migrating and transforming various carbon components, including particulate organic carbon, dissolved inorganic carbon, and dissolved organic carbon. Riverine carbon cycling models are classified into two types: statistical and process-based. The representative models’ simulation methods, applications, advantages, and disadvantages were compared. Based on statistical or machine learning methods, empirical statistical models establish the relationship between the riverine carbon flux and environmental factors. This type of model is simple but has poor extrapolation and universality. Process-based models are based on land surface or hydrological models coupled with river carbon cycling-related biogeochemical processes. This model simulates and predicts variations in different riverine carbon fluxes and is more reliable but complicated. Such models typically focus on different scientific problems, and the representations of riverine carbon cycling-related processes differ among these models. Simulation research on riverine carbon cycling is still in its early stages; however, many shortcomings remain. For example, the representations of terrestrial and aquatic carbon cycling and human activities in existing riverine carbon cycling models are insufficient; thus, they cannot accurately simulate and predict long-term changes in riverine carbon cycling. In the future, it will be necessary to strengthen observations of river carbon cycling processes and improve our understanding of terrestrial and aquatic carbon cycling to represent the mechanisms and processes in the model. This will improve the accuracy of riverine carbon cycling simulations and provide a scientific basis for China to achieve its double-carbon goals.

In urban areas with infrequent rainstorms and rapid flow routing, an integrated approach combining sponge city technology and coordinated hydraulic structure management proves effective in mitigating urban flooding/waterlogging disasters, optimizing urban water resource distribution, and curbing flood cascades. This paper provides a summary of the history and research advancements of sponge city construction in China, along with an analysis of the flood prevention and drainage capabilities of sponge city technology. Subsequently, typical measures and research progress in urban hydraulic structure scheduling are summarized, and the functions of the combined use of sponge city measures and hydraulic structure scheduling in flood prevention and drainage are analyzed. Building upon this analysis and investigation, the study focuses on the downtown area of Fuzhou City to examine the roles played by the integrated use of sponge city technology and hydraulic structure scheduling in urban flooding/waterlogging prevention and mitigation.

Marine carbon storage plays a crucial role in reducing global greenhouse gas emissions. To ensure the efficient and safe storage of CO₂, it is imperative to monitor the potential migration of CO₂ before, during, and after injection. Current methods for monitoring marine carbon storage encompass built-in sensor monitoring focusing on the seabed wellbore, geophysical monitoring targeting reservoirs and caprocks, and marine environmental monitoring focusing on the seafloor and water column. These three methods can be used to obtain temperature/pressure/acoustic data near the injection/monitoring wellbore, seismic/electromagnetic/gravity data of deep reservoirs and caprocks, and acoustic/chemical/oceanographic data of near-bottom sedimentary layers and seawater, respectively. Analyzing these datasets is expected to reveal the migration characteristics of CO₂ injected into the formation. However, the integrated use of relevant monitoring methods and technologies and the design of high-quality monitoring strategies currently pose significant challenges for both academic and engineering communities. To enable scientific and systematic monitoring of the safety of marine carbon storage, offering essential guidance for offshore storage operations, and concurrently enhancing monitoring efficiency while reducing monitoring costs, we have compiled the fundamental principles, application status, and challenges encountered by different monitoring methods and technologies. We also anticipate future development of monitoring technologies for marine carbon storage.

Watershed geomorphology and river network structure controlled by tectonic frameworks, regional climate, vegetation, and biological factors are the combined results of the long-term internal and external forces of the Earth. Owing to the different tectonic, lithological, and climatic conditions in various regions, different watersheds have different geomorphic and river network structural characteristics that influence hydrological response mechanisms. In this study, the characteristic parameters for a quantitative description of the watershed geomorphic system and river network morphology are presented, and the impacts of tectonics, lithology, climate, and other factors on watershed geomorphology and river network structures are reviewed. Based on this, it is emphasized that reproducing the evolution of watershed geomorphology and quantifying its main controlling factors is the main problem. Subsequently, the birth, development, and application of the geomorphic evolution model are expounded. Finally, it is suggested that the main future development direction should involve combining traditional geomorphological research methods and geomorphic evolution models to study the influencing mechanisms of watershed geomorphology and river network structure.

In 2015, the “2030 Agenda for Sustainable Development” (2030 ASD), adopted by the United Nations, set 17 Sustainable Development Goals (SDGs). Scholars worldwide have conducted continuous research on the monitoring and evaluation of SDGs. Data deficiency and inadequate index monitoring abilities are considered vital restrictions in the regular monitoring and evaluation of SDGs. The application of Multisource Data to the monitoring and evaluation of SDGs can effectively address these deficiencies. Research progress on SDGs based on Multisource Data can be categorized into three types: the first type focuses on the basic theory and method system of SDG monitoring and evaluation based on Multisource Data; The second type conducts SDG monitoring and evaluation case studies based on Multisource Data; The third type focuses on strengthening the primary capacity building related to Multisource Data. The application of multisource data can strengthen the evaluation of natural ecosystems, identify critical areas, analyze the interaction between humans and nature, effectively compensate for the lack of data and other deficiencies, and improve the timeliness and spatial and temporal resolution of indicator data, which can significantly enrich the evaluation index system of the SDGs. This study proposes to strengthen the application of Multisource Data in the study of SDGs from four aspects: to expand the application of Multisource Data in the SDGs, promote interdisciplinary and comprehensive research, pilot the application of Multisource Data in the national innovation-driven demonstration zone for implementing the UN's 2030 ASD, and strengthen the primary capacity building of Multisource Data.

The Anthropocene Working Group (AWG) of the International Commission on Stratigraphy voted that the Anthropocene should be defined by a Global boundary Stratotype Section and Point (GSSP or ‘golden spike’) as a formal chronostratigraphic unit. Increasing evidence has shown that human activities have drastically intensified since the mid-twentieth century, altering the original rate and direction of Earth’s evolution, triggering a profound impact on Earth’s environment, and leaving their imprint on geological records through physical, chemical, and biological markers. Consequently, the 1950s was assumed to be the ideal onset of the Anthropocene. Currently, 12 candidate sites for the GSSP of the Anthropocene have been proposed for consideration by the AWG. Chinese researchers have made outstanding progress in recent years regarding the establishment of a system of proxies for human activities and the global comparison of the candidate sites for the GSSP of the Anthropocene. These proxies, including anthropogenic radioactive isotopes, microplastics, δ¹³C, δ¹⁵N, and diatoms, have great potential as markers of human activities. These proxies recorded in the sediments of Sihailongwan Maar Lake, which is far away from cities and less affected by human activities, indicate that this site is sensitive to global change. The concentrations of ^{239, 240}Pu have drastically increased since 1953 CE in the sediment profile collected from Sihailongwan Maar Lake. as Additionally, other proxies such as PAHs, ¹²⁹I, soot ¹⁴C, SCP (spheroidal carbonaceous particles), DNA, δ¹³C, and Pb exhibit synchronous changes near 1953 CE, indicating the onset of Anthropocene. Two sediment stratotype profiles collected from Sihailongwan Maar Lake and Beppu Bay, Japan, were selected by the AWG as auxiliary sections for the GSSP of the Anthropocene. The ultimate goal of Anthropocene science should be to deepen the theory and technological innovation of sustainable development of the Earth-humans system and adaptation based on clarifying the impact of human activities on the Earth system.

The International Earth Rotation and Reference Systems Service (IERS) released the updated International Terrestrial Reference Frame ITRF2020 in April 2022 (the International Terrestrial Reference Frame 2020). The accuracy of ITRF2020 is better than that of ITRF2014 because of the adoption of a longer time series, better processing models, and more optimized processing strategies. Compared with ITRF2014, ITRF2020 has significant improvements in the strategies for implementation of origin and scale parameters, and for the first time it explicitly provides the origin, scale, and orientation of seasonal signals; that is, \mathrm{①} the strategy of segmented alignment is adopted to improve the origin and scale parameter realization; \mathrm{②} the origin, scale, and orientation realizations of seasonal signals in the Center of Mass (CM) and Center of Figure (CF) frames, as well as the harmonic parameter models in the CM and CF frames, are given. In addition, there have been significant technological advances in data processing for each of the independent techniques involved in the construction of ITRF2020. In this paper, we first introduce in detail the progress of data processing within the four space geodetic technologies and the technical progress of the inter-technology combinations, then briefly analyze the ITRF2020 implementation, and finally provide a preliminary analysis and discussion of its shortcomings.

Globalization and elevated atmospheric Nitrogen (N) deposition have significantly altered the terrestrial carbon cycle. Soil microbial Carbon Use Efficiency (CUE) plays a key role in adjusting soil cycling rates and processes and is also an important parameter in soil C cycle models. However, the effects of elevated N deposition on soil microbial CUE are often inconsistent, which limits the reliability of predictions of both soil C cycle dynamics and C storage capacity under global changes. Here, we review advances in research on soil microbial CUE and measurement methods. We further explore the mechanisms underlying the effects of increased nitrogen deposition on CUE from both biological and abiotic perspectives in forest ecosystems. In terms of biological mechanisms, N deposition can affect CUE by changing microbial biomass and community structure and by regulating microbial enzyme activities. In terms of abiotic mechanisms, N deposition can affect CUE by changing the N addition-induced changes in the soil nitrogen state, soil stoichiometry, soil pH, and aboveground vegetation dynamics (such as root exudates and litter input), which can independently or jointly affect soil microbial CUE. In general, moderate nitrogen deposition can alleviate ecosystem nitrogen limitation and stimulate microbial activity, thus increasing soil microbial CUE. In contrast, excessive N deposition decreases microbial CUE by inhibiting microbial growth. Lastly, the potential research activities and recommendations for future research are presented. Therefore, it is imperative to optimize the determination of microbial CUE for comparative research among different ecosystems. At temporal and spatial scales, more attention should be paid to the interaction effects of multiple factors under global changes, so that there is a strong theoretical basis for evaluating and predicting the soil carbon sequestration capacity in forest ecosystems.

The Paleoproterozoic Great Oxidation Event (GOE, approximately 2.43~2.06 Ga) is the first significant atmospheric oxygen increase and fundamentally changed the environment and habitability of the Earth. This study summarizes the research progress on the GOE and related carbon cycle perturbation events in the early and middle Paleoproterozoic, focusing on the time frame, initiation process, and mechanism of the GOE, extremely δ¹³C_carb-positive excursion event (Lomagundi-Jatuli event), and carbon cycle perturbation events after the GOE. The initiation of the GOE was intermittent, and research on the initiation mechanism presents diverse viewpoints. The atmosphere-ocean system experienced oxidation and deoxygenation processes during the Lomagundi-Jatuli event, in which the initiation mechanism may have been caused by the increase in ocean primary productivity during this period, but the influence of other mechanisms (such as the deep carbon cycle of the Earth) cannot be ruled out. After the Lomagundi-Jatuli event, global organic carbon burial increased significantly and lasted until approximately 1.7 Ga (Shunga event), during which there was a δ¹³C_carb-negative excursion event (Shunga-Francevillian event). The mechanism of the Shunga and Shunga-Francevillian events remains to be studied.

Inland water is an important source of global methane (CH₄) emissions, and CH₄ emitted through ebullition accounts for a large proportion of the total CH₄ emissions from inland waters. Here, the latest progress in domestic and international research has been systematically summarized to introduce the generation, transport, oxidation, and release of CH₄ via ebullition in inland waters as well as the methods and techniques for measuring CH₄ ebullition. Subsequently, temporal and spatial variations in CH₄ ebullition from global inland water were compared at different temporal and spatial scales. In addition, the mechanisms of the relevant influencing factors in the processes of CH₄ generation and ebullition are further summarized, and current development and applications of CH₄ ebullition models are discussed. Finally, potential research directions and challenges related to CH₄ ebullition from inland water are proposed, aiming to provide a basis for subsequent research on CH₄ ebullition, investigation of process and control mechanisms, and model development and estimation in this field.

The acceleration of urbanization and population agglomeration intensifies the Urban Heat Island (UHI) effect and causes Heat Waves (HWs). The superimposed effects of the two seriously affect urban development and resident health. A few studies believe that HWs and UHI intensity have the characteristics of synergistic enhancement, but there are still large differences in the superimposed effects of HW-UHI. This article comprehensively reviews and summarizes domestic and foreign research on the differences in the synergy between HWs and UHI and explores the formation mechanism of urban high temperatures from the aspects of climate background, local circulation, and urban morphology. Under different climatic backgrounds and local circulation conditions, the synergistic effects of the HW-UHI show significant spatiotemporal differences, particularly the regulatory role of local circulation, which cannot be ignored. The Local Climate Zone (LCZs) classification proposed in the past decade has achieved some results in research on the synergy between HWs and UHI; however, it is necessary to further explore their response characteristics from the three-dimensional morphology of the city. Currently, there is no unified standard definition for HWs, which brings uncertainty to an in-depth understanding of HW-UHI interactions. There is a need to comprehensively understand the spatiotemporal differences in excessive urban warming caused by HW and UHI and their formation mechanisms and regulating factors to provide more detailed guidance and theoretical support for high-temperature monitoring and improvement of the urban living environment.

N₂O is an important greenhouse gas that also damages the ozone layer. N₂O emissions have been observed during microalgae cultivation and in microalgae-based ecosystems, such as eutrophic lakes. However, little has been reported on the important role of the N₂O balance in algae and the potential algal N₂O production pathways. A review of recent relevant studies on N₂O synthesis and fixation by algae shows that the studies mainly focus on the relationship between algae and N₂O emissions, several possible pathways of N₂O production and consumption in algae, the influence of the algal microenvironment on the distribution pattern of N₂O, and the potential impacts on global climate change. However, the Intergovernmental Panel on Climate Change currently does not consider the possible N₂O emissions during algal blooms or algal aquaculture; hence, it is necessary to intensify experimental studies related to algal N₂O production globally to take important steps towards a comprehensive clarification of the important roles of algae in N₂O emission and fixation and a comprehensive assessment of greenhouse gas emissions from aquatic ecosystems.

Global warming caused by human activities has resulted in significant changes in the climate system, including changes in the regional climate, extreme events, snow, ice, vegetation, air quality, water cycle, and responses and feedbacks among various components of the climate system. The land surface is where water, energy, and geochemical transports to and from the atmosphere occur, hydrological processes occur, and vegetation grows. Hence, the land surface is sensitive to climate change. Climate change affects the hydrological processes not only directly but also indirectly by affecting the vegetation structure and physiology. Land surface models are useful for studying climate change and its impacts on the land surface by modeling the relevant responses and feedbacks. There are three types of land surface models that simulate the mass and energy exchange between the land surface and atmosphere: the global land surface process model, global hydrological model, and global dynamic vegetation model. These three types of models focus on different specific components of the land surface. Since the 1990s, various land surface comparison projects have revealed many problems and shortcomings in land surface models and have furthered their development. However, various issues with these models still need to be addressed. For example, one major problem with the global hydrological model is that it does not incorporate dynamic vegetation growth; hence, it cannot project long-term vegetation change impacts on the hydrological processes—let alone extreme hydrological events such as flooding and drought—and cannot be useful with respect to future water resource management. Incorporating dynamic vegetation growth into hydrological models is a frontline research topic in hydrology. Moreover, many land surface models represent soil textures and heat exchanges among soil liquids, solids, and gases on the Tibetan Plateau insufficiently. This aspect requires improvement by enhancing the observations, understanding the relevant mechanisms, and realizing the mechanisms and processes in the land surface models. The Tibetan Plateau provides fresh water to the surrounding regions and forms and modulates climate and weather both regionally and globally; thus, it is dubbed the Asian Water Tower. Improving the land surface model capability of the plateau will improve the understanding of climate change and its impacts, both regionally and globally.

Division V (Atmospheric Discipline) of the Department of Earth Sciences, National Natural Science Foundation of China (NSFC), successfully completed the application, review, funding, and conclusion of the centralized receipt of the Program in 2023. In terms of program applications, Division V of the Department of Earth Sciences received 1 928 applications from the General Program, Young Scientists Fund, and Fund for Less Developed Regions in 2023, indicating an increase of 6.1% over the applications in 2022. Two applications were rejected because of non-compliance with management standards in 2023, and this result is an improvement compared to previous years. Atmospheric Discipline received 62 applications for National Science Fund for Distinguished Young Scholars, 92 applications for Excellent Young Scientists Fund, and 49 applications for key program in the field of ‘Weather, climate, and associated sustainable development.’ From the perspective of reviews, the comprehensive evaluation scores of communication reviews for the General Program, Young Scientists Fund, and Fund for Less Developed Regions increased compared to the previous two years. This review clarifies the positioning of the “supporting technology” section to support programs that are truly engaged in key technology research and development. In terms of funding, the total number of the three types of funds reached 417, and the average funding rate was 21.6%, which was lower than that in 2022. In total, 319 projects were concluded in 2022, and performance indicators, such as the number of published papers, were comparable to those in previous years.

Quantitative assessments of progress towards Sustainable Development Goals (SDGs) and the complex interactions of indicators are critical for monitoring the achievement of SDGs and guiding policymaking and implementation. Based on Big Earth Data and the SDGs global indicator framework, an index system for evaluating progress towards SDGs in frontier, multi-ethnic underdeveloped areas was developed from the perspective of social, economic, and environmental dimensions and included 70 indicators. The study area was the National Innovation Demonstration Zone (Lincang) for the 2030 Agenda for Sustainable Development. The model incorporated regional characteristics and data acquisitioned from Lincang in 2015-2020 through field research. Consequently, we calculated the social, economic, and environmental sub-indices and integrated index of sustainable development of Lincang City from 2015 to 2020, evaluated the progress trend of SDGs and indicators, and proposed key challenges and solutions for the sustainable development of Lincang City. Research shows that the integrated index and the social, economic, and environmental sub-indices of sustainable development have shown an increasing trend from 2015 to 2020. In terms of the SDGs, progress was achieved with respect to all 16 SDGs. The average annual growth rate of SDG 5 was the highest, whereas that of SDG 13 remained unchanged. In addition, 81% of indicators showed acceptable progress. This study provides a reference for sustainable development planning in other typical demonstration areas and underdeveloped mountainous areas in China and worldwide.

Ocean aerosols are of important because of their climatic and environmental effects. When bubbles in seawater rise to the surface and burst, they enrich the surface-active substances present in the sea-surface microlayer into Sea Spray Aerosol (SSA), thus affecting their physical and chemical properties. In this study, the sources and quantitative characterization methods for marine surface-active substances are reviewed. The effects of surface-active substances on the concentration and particle size distribution of SSA are addressed, and the influencing mechanisms of hygroscopicity, cloud condensation nucleation activity, and ice nucleation activity are summarized. Owing to different sources, types, and other environmental conditions; the effects of surface-active substances on SSA generation and physicochemical properties vary significantly, making it difficult to study the environmental and climatic effects of SSA. In the future, further observational and modeling research on surface-active substances is required to provide scientific support for improved regional and global modeling of SSA.

Glycerol Dialkyl Glycerol Tetraethers (GDGTs) are structurally stable, ubiquitously distributed, climate-sensitive microbial biomarkers that serve as important proxies for paleoclimatic and paleoenvironmental reconstruction. Compared to other regions, the extreme environment of the Tibetan Plateau triggers complex microbial responses that cause variations in GDGT distribution characteristics across various archives. These introduce uncertainties that limit the full potential of GDGTs in paleoclimate studies on the Tibetan Plateau. This paper summarizes the distribution, sources, and influencing factors of GDGTs in different Tibetan Plateau archives. It also outlines GDGT-based paleotemperature reconstructions, along with their associated uncertainties. The sources of uncertainty and their explanatory mechanisms are highlighted. Finally, considering the interactions between earth system spheres affecting GDGT proxies on the Tibetan Plateau, perspectives on GDGT research across the Tibetan Plateau archives are discussed, and future directions are proposed.

The global Ocean General Circulation Model (OGCM) is a critical component of Earth system modeling and plays an essential role in climate projections and marine environmental forecasting. Herein, the history of global OGCM models is systematically reviewed and significant scientific and recent technological advancements are summarized. This review covers three topics involving the core technology of OGCMs: the dynamical core, physics or physical parameterization, and soft-hardware configuration. In the dynamic core, the latest developments in horizontal discretization methods, vertical coordinate schemes, and multi-resolution strategies are explored. Regarding physics, the focus has been on the progress of mesoscale, sub-mesoscale, and boundary-layer mixing parameterizations. In the soft-hardware configuration section, the current status and prospects for the application of heterogeneous computing architectures and artificial intelligence technology in global OGCMs are discussed. The advancement of the LASG/IAP Climate System Ocean Model, a fully autonomous Chinese global OGCM, is also highlighted. Based on key trends and novel ideas in the field of global OGCMs, suggestions are provided for Chinese researchers and relevant policymakers to comprehensively advance R&D strategies and long-term planning for fully autonomous global OGCMs.

The mutual interaction between coastal aeolian landforms and vegetation has been the focus of research in different periods, both domestically and internationally. This brief review summarizes the main advancements in research on the interaction between coastal aeolian landforms and vegetation, as well as the techniques and methods used. Research improvements are necessary in terms of systematic analysis, deepening the understanding of the impact and response mechanisms of vegetation on dune evolution, and addressing the lack of regional comparative studies. This review proposes future research directions that advocate for an intensified examination of landscape effects resulting from the interaction between coastal aeolian landforms and vegetation. It further suggests a deeper exploration of the response patterns of vegetation to the morphological and dynamic processes of coastal aeolian landforms, clarification of the feedback mechanisms between coastal vegetation and aeolian landform morphology and activity, and increased emphasis on regional comparative studies. This will enrich and enhance the research on coastal aeolian landforms in China.

Black shale is the product of the joint action of life and non-life processes under the condition of multi-circle linkage in the deep inside and on the surface of the Earth and contains abundant energy resources indispensable for social development. To comprehensively understand the research status of black shale in China, clarify the notable research topics, deeply assess the research frontiers and hot spots, and grasp their development trends; a knowledge graph analysis of the literature on black shale in China included in the CNKI (1 466 articles) and Web of Science (1 069 articles) databases was performed using CiteSpace visualization software. The results showed that the number of published papers has increased annually since the beginning of this century, inter-institutional and international cooperation has gradually strengthened, and academic influence has notably expanded. The core research topics included shale gas, Longmaxi Formation, the Sichuan Basin, and other keywords. The research frontier clusters cover 12 subdomains, including “Southern North China Basin”, “Wufeng-Longmaxi Formation”, “Ordovician-Silurian Transition”, “Early Cambrian”, “Ni-Mo Polymetallic Sulfide Bed”, “Ediacaran Radiogenic Sr Isotope Excursion”, “Ordovician-Silurian Wufeng-Longmaxi Shale”, “Ordos”, “South China”, “Shale Gas Potential”, “Cambrian Facies”, and “Early Cambrian Black Shale”. The research on black shale in China is concluded to be in a stage of rapid development, with the most notable research discipline being petroleum geology. The hottest research area is the Sichuan Basin, and the hottest strata include the Wufeng-Longmaxi and Niutitang formations. Frontier research topics have shifted from mineral deposits and sedimentology to petroleum geology. Overall, biased attention has been given to black shale research in China in terms of the discipline, targeted regions, and strata. Multidisciplinary collaborative research remains rare, and its scientific strengths require to be adequately explored. In addition, the study of black shale has been mainly limited to sedimentary environments and redox conditions, whereas the sedimentary processes and mechanisms have not been adequately studied. Currently, an urgent requirement prevailsto strengthen interdisciplinary cooperation and integration and perform major comprehensive research projects on black shale to lead scientific research frontiers and serve the developmental needs of our country.

The conductance-photosynthesis (g_s-A) model is widely used for estimating the transpiration rate (ET_c). The stomatal conductance slope (g₁) in the g_s-A model is crucial, and is usually parameterized with a PFT-specific g₁. However, because there is seasonal variation in g₁, the scheme of constantizing g₁ results in large potential uncertainties in ET_c estimation. Therefore, optimizing the parameterized scheme of g₁ is key for improving the estimation of ET_c. Previous studies have shown that the dynamic parameterization of g₁ using remote sensing-based Leaf Area Index (LAI) can effectively improve the accuracy of the estimated ET_c in deciduous forests. However, it is still not clear whether this method is applicable to evergreen forests, in which the canopy shows slight seasonal variability. In addition, the First-Principles Theory indicates that g₁ can be expressed as a function of temperature. Hence, whether temperature can be used to simulate g₁ with a better performance than that when using LAI requires further investigations. In view of the above questions, six FLUXNET evergreen forest sites were selected to investigate the relationships between g₁, and LAI and air temperature, and the ET_c simulation results under the two parameterization schemes were compared. Results showed that g₁ varied with both LAI and temperature at each site, showing a significant negative correlation, while the results of the dynamic parameterization scheme (DYN) were better than those of the constant g₁ scheme (FIX). This showed that the simulation of g₁ using LAI is still effective in evergreen forests, but the explanation of temperature on g₁ (R²=0.45±0.12) is stronger than that of LAI (R²=0.28±0.23). Further comparing the g_s and ET_c obtained using the two schemes, we found that the scheme based on temperature performed better than that of LAI at the daily scale, with the Root Mean Square Error (RMSE) of the ET_c estimation being significantly reduced (26.0%±24.4%). This study emphasizes the feasibility of the temperature-based parameterized scheme of g₁ and helps to fundamentally improve the simulation of g_s and ET_c in evergreen forest landscapes.

Satellite-based fast inversion for nitrogen oxides (NO _x =NO+NO₂) emissions at low computational costs and high resolutions (≤5 km or finer) can provide timely, detailed data to support targeted pollution control. To date, a variety of low-cost fast inversion methods have been developed, such as the Exponentially Modified Gaussian (EMG), Divergence (DIV), and the PHLET (Peking University High-resolution Lifetime-Emission-Transport) models. However, quantitative comparisons of these methods and their emission results are lacking. This study compares the above three inversion methods for the Beijing-Tianjin-Hebei region during the summer of 2019. We found that the EMG model, which was designed for point source emission inversion, performs poorly in Beijing-Tianjin-Hebei due to dense emission sources even within each city. The DIV considers the horizontal transport of NO _x with a predetermined (fixed) lifetime and can quickly identify the locations of emission sources; however, it tends to underestimate the emission amounts and even leads to negative emissions in many places. PHLET algorithm considers the horizontal transport of NO₂, the nonlinear relationship between local NO₂ concentrations and lifetimes, and the two-way matching between irregular satellite pixels and regular model grid cells, resulting in more reliable emission estimates. Filling in missing satellite data through data fusion, improving wind data resolution and accuracy, and improving NO _x chemical loss estimation will significantly enhance the quality of emission inversion.

As computing power continues to improve, the horizontal grid resolution of numerical weather prediction models has reached the kilometer-to-sub-kilometer scale. This grid scale is comparable to the characteristic turbulent scales in the convective boundary layer, allowing the numerical models to resolve the organized convective structures. The assumptions of traditional one-dimensional boundary layer parameterization schemes (suitable for horizontal resolutions of several kilometers or coarser) and large eddy simulation three-dimensional turbulent closure schemes (suitable for horizontal resolutions below several tens of meters) do not hold at this scale, which is referred to as the gray zone. This study discusses the applicability and limitations of traditional parameterization methods and introduces the gray zone of the convective boundary layer from three perspectives: theory, methodological approaches, and impact. It summarizes the characteristics of the simulation methods at the CBL gray zone scale developed over the past two decades and explores the impact of the boundary layer process simulation at this scale on other physical processes (e.g., shallow/deep convection) in numerical models. Further, we anticipate future research directions and approaches.

Research on the Anthropocene—a newly determined geological chronological unit—requires higher temporal resolution, which necessitates the identification of appropriate dating methods. Currently, the main dating methods involve ¹³⁷Cs, ²¹⁰Pb, and ^{239, 240}Pu isotopes. Compared with ¹³⁷Cs and ^{239, 240}Pu dating, ²¹⁰Pb dating has a wider application range, relatively stable geochemical behavior and distribution in the environment, and relatively high dating reliability. It can be used to estimate sedimentation rates in Anthropocene estuaries, lakes, oceans, and other sedimentary environments. This paper summarizes the ²¹⁰Pb dating method, dating principle, and model, and expounds the application of ²¹⁰Pb dating for the establishment of the Anthropocene age scale and acquisition of sedimentary rates in different sedimentary environments, such as estuaries, lakes, and oceans. It also discusses its influencing factors, and indicates that there are certain error sources in the ²¹⁰Pb dating method, such as changes in sedimentary rates, which require further study. Future research should combine ²¹⁰Pb dating with other dating methods to obtain a more comprehensive and accurate Anthropocene chronological framework. ²¹⁰Pb will continue to play an important role in the study of the Anthropocene, helping us to better understand the history and future of Earth.

The matching of water and land resources often directly affects food production in various regions and is the basis for high-quality economic and social development and modernization of agricultural production. Using nine provinces along the Yellow River as examples, based on the cross-coupling of four elements, such as the natural background of water resources and water resources for total water consumption control, this study constructed a ternary synergistic model of water-cultivated land-grain by cross-coupling. The matching coefficients of water and soil resources from 2010 to 2020 under each scenario were calculated, and the temporal and spatial evolution characteristics of water and soil resources matching along the “province-city” scale of the nine provinces along the Yellow River and the contribution degree of each element were analyzed. The results showed that: \mathrm{①} The matching degree of binary water and soil resources based on the natural background of water resources in the nine provinces was improved as a whole, and the matching pattern of water and soil resources was relatively stable; however, the regional differences are notable and manifested as “high in the west and low in the east.” \mathrm{②} Along the three-way coordinated matching pattern of water-arable land and grain in the nine provinces, from the perspective of the total amount of cultivated land and the amount of irrigated arable land in the natural background of water resources, roughly three distribution patterns were presented: the western and northeastern regions were severely water-deficient areas, the northern and north-central regions typically had varying degrees of water shortage, and the central and eastern regions exhibited a diversified distribution pattern; from the perspective of total water consumption control, a remarkable difference is observed between the total amount of cultivated land and the three-way cooperative matching pattern of irrigated cultivated ground. \mathrm{③} Under the four scenarios, the average contribution rate of water resources were >50%, and the sum of the effective utilization coefficient of irrigation water and the contribution rate of the irrigation quota were >30%, indicating that increasing the effective utilization coefficient and setting a reasonable irrigation quota had a decisive impact on the change in water and soil resource matching. These results improve our understanding of the relationship between water resources and exploitation, cultivated land production capacity, and reclamation, as well as the interdependence and constraints of the grain planting structure.

Based on a global comparison of geological records, the International Anthropocene Working Group (AWG) determined that the onset of the Anthropocene was sometime in the mid-twentieth century (~1950 CE), and the Sihailongwan Maar Lake has been included as one of the candidate sites for the Global boundary Stratotype Section and Point (GSSP) of the Anthropocene. However, humans had a profound impact on the environment of the areas around Sihailongwan Maar Lake even before 1950 CE. Historical sequences of TOC contents, C/N ratios, δ¹³C_org values, Ca/Ti ratios, and concentrations of silicate major elements, such as Si, Al, and K, since 900 CE were reconstructed, with the average resolution being ~10 a, to explore the history of human activities in this region under the background of climate change. Human activities have significantly increased since 1850 CE, and changes in the measured proxies during the Medieval Warm Period and Little Ice Age before 1850 CE generally follow natural laws. The changes in the measured proxies during 1850-1950 CE indicate a rapid population growth, which damaged vegetation and resulted in intensified weathering and deviation of the surface environment evolution from the natural state. Hence, humans had started to be an important force for the geological environment; nevertheless, the changes during this period resulted in mostly local signals. After 1950 CE, the C/N ratios and δ¹³C_org values decreased continuously, indicating that the environmental status of the area around Sihailongwan Maar Lake changed once again under the new government and advanced productivity. This was in sync with the Great Acceleration of the global geological environment and supports the conclusion of the AWG that the onset of the Anthropocene was sometime in the mid-twentieth century.

Aquatic ecosystems are a significant source of methane emissions. Although methane production has previously been recognized to only occur in oxygen-deprived environments, recent research has shown that aerobic water environments also experience high methane levels, known as the “methane paradox”. This phenomenon is linked to the presence of algae that can directly produce methane through photosynthesis or the use of specific compounds. Moreover, algae create conditions conducive to methane production by other microorganisms. However, the specific ecological mechanism of aerobic methane production by algae remains not yet fully understood, making accurate global methane level accounting difficult. Future studies should focus on uncovering the molecular regulation of aerobic methane production by algae and how they adapt to external conditions.