Driven by the global energy transition and the urgent“dual carbon”goals,regional integrated energy system(RIES)planning is undergoing a paradigm shift from carbon reduction to negative carbon emissions.This paper pr...Driven by the global energy transition and the urgent“dual carbon”goals,regional integrated energy system(RIES)planning is undergoing a paradigm shift from carbon reduction to negative carbon emissions.This paper provides a comprehensive review of the theoretical frameworks and technical pathways for RIES planning from a carbon-centric perspective.A key contribution is the proposed Carbon-Energy-Economy(CEE)triple-dimensional governance framework,which endogenizes carbon factors into planning decisions through emission constraints,trading mechanisms,and capture technologies.We first analyze the fundamental characteristics of RIES and their critical role in achieving carbon neutrality,detailing advancements in multi-energy coupling models,energy router concepts,and standardized energy hub modeling.The paper further explores multi-energy flow analysis methods,and systematically compares the applicability and limitations of various planning algorithms,with emphasis on addressing uncertainties from renewable integration.Finally,we highlight the integration of artificial intelligence with traditional optimization methods,offering new pathways for intelligent,adaptive,and low-carbon RIES planning.This review underscores the transition towards data-physical fusion models,cooperative uncertainty optimization,multi-market planning,and innovative zero/negative-carbon technological routes.展开更多
The neutral surface of a concave thin mirror is too close to the mirror surface,which makes it difficult to effectively mount the flexible structure and increases the mirror surface shape error.To address this problem...The neutral surface of a concave thin mirror is too close to the mirror surface,which makes it difficult to effectively mount the flexible structure and increases the mirror surface shape error.To address this problem,we design a flexible support structure including connectors,a support plate,and flexible structures,and construct an equivalent mirror by installing connectors and a support plate on the back of the mirror.While ensuring that the neutral surface of the equivalent mirror is moved away from the mirror surface,we optimize the support structure so that the rotary center of the flexible structure is located on the neutral surface of the equivalent mirror,avoiding the tilting moment.Following design and modeling of the structure,we analyze the static and dynamic characteristics using a finite element simulation,finding a root-mean-square(RMS)value for the surface shape error of 9.28 nm under the coupled effects of 1g gravity load,4℃ temperature rise,and 0.005 mm unevenness assembly error,with a fundamental frequency of 170.75 Hz,which all meet the design requirements.Finally,we carry out a surface shape error test of the mirror assembly,confirming it to meet the design index requirement of the mirror assembly.Simulation and test results verify the reliability and effectiveness of our proposed support structure.展开更多
Electrocatalytic nitrate reduction reaction(NO3RR)represents a sustainable and environmentally benign route for ammonia(NH3)synthesis.However,NO3RR is still limited by the competition from hydrogen evolution reaction(...Electrocatalytic nitrate reduction reaction(NO3RR)represents a sustainable and environmentally benign route for ammonia(NH3)synthesis.However,NO3RR is still limited by the competition from hydrogen evolution reaction(HER)and the high energy barrier in the hydrogenation step of nitrogen-containing intermediates.Here,we report a selective etching strategy to construct Ru M nanoalloys(M=Fe,Co,Ni,Cu)uniformly dispersed on porous nitrogen-doped carbon substrates for efficient neutral NH3electrosynthesis.Density functional theory calculations confirm that the synergic effect between Ru and transition metal M modulates the electronic structure of the alloy,significantly lowering the energy barrier for the conversion of*NO_(2)to*HNO_(2).Experimentally,the optimized Ru Fe-NC catalyst achieves 100%Faraday efficiency with a high yield rate of 0.83 mg h^(-1)mg^(-1)catat a low potential of-0.1 V vs.RHE,outperforming most reported catalysts.In situ spectroscopic analyses further demonstrate that the Ru M-NC effectively promotes the hydrogenation of nitrogen intermediates while inhibiting the formation of hydrogen radicals,thereby reducing HER competition.The Ru FeNC assembled Zn-NO_(3)^(-)battery achieved a high open-circuit voltage and an outstanding power density and capacity,which drive selective NO_(3)^(-)conversion to NH3.This work provides a powerful synergistic design strategy for efficient NH3electrosynthesis and a general framework for the development of advanced multi-component catalysts for sustainable nitrogen conversion.展开更多
Global land monsoon precipitation(GLMP)is highly sensitive to changes in interhemispheric thermal contrast(ITC).Amplified interhemispheric asymmetries of GLMP due to enhanced ITC driven by high-level anthropogenic emi...Global land monsoon precipitation(GLMP)is highly sensitive to changes in interhemispheric thermal contrast(ITC).Amplified interhemispheric asymmetries of GLMP due to enhanced ITC driven by high-level anthropogenic emissions are expected to simultaneously increase the probability of regional floods and droughts,threatening ecosystems within global terrestrial monsoon regions and the freshwater supply for billions of residents in these areas.In this study,the responses of GLMP to the evolution of ITC toward the carbon neutrality goal are assessed using multimodel outputs from a new model intercomparison project(CovidMIP).The results show that the Northern Hemisphere-Southern Hemisphere(NH-SH)asymmetry of GLMP in boreal summer weakens during the 2040s,as a persistent reduction in well-mixed greenhouse gas(WMGHG)emissions leads to a downward trend in the ITC after 2040.At the same time,the reduction in WMGHG emissions dampens the Eastern Hemisphere-Western Hemisphere(EH-WH)asymmetry of GLMP by inducing La Niña-like cooling and enhancing moisture transport to Inner America.The resulting increases in land monsoon precipitation(LMP)may alleviate drought under the global warming scenario by about 19%-25%and 7%-9%in the WH and SH monsoon regions,respectively.However,a persistent reduction in aerosol emissions in Asia will dominate the increases in LMP in this region until the mid-21st century,and these increases may be approximately 23%-60%of the growth under the global warming scenario.Our results highlight the different rates of response of aerosol and WMGHG concentrations to the carbon neutrality goal,leading to various changes in LMP at global and regional scales.展开更多
Nuclear energy is critical not only to sustainable economic development but also to achieving peaking carbon dioxide emissions and carbon neutrality[1].China is expected to host the world’s largest number of nuclear ...Nuclear energy is critical not only to sustainable economic development but also to achieving peaking carbon dioxide emissions and carbon neutrality[1].China is expected to host the world’s largest number of nuclear power plants in a few years.Uranium-235 serves as the primary fissile material for the fabrication of nuclear fuel.However,there are only about 6.14 million tons of uranium resources on land,which can sustain~70 years of operation for global nuclear power plants.Thereby,the recovery of uranium from spent fuel,radioactive waste solutions,seawater,and salt lakes is crucial for the healthy development of nuclear power utilization[2-4].展开更多
When performing English-to-Tamil Neural Machine Translation(NMT),end users face several challenges due to Tamil's rich morphology,free word order,and limited annotated corpora.Although available transformer-based ...When performing English-to-Tamil Neural Machine Translation(NMT),end users face several challenges due to Tamil's rich morphology,free word order,and limited annotated corpora.Although available transformer-based models offer strong baselines,they compromise syntactic awareness and the detection and man-agement of offensive content in cluttered,noisy,and informal text.In this paper,we present POSDEP-Offense-Trans,a multi-task NMT framework that combines Part-of-Speech(POS)and Dependency Parsing(DEP)methods with a robust offensive language classification module.Our architecture enriches the Transformer encoder with syntax-aware embeddings and provides syntax-guided attention mechanisms.The architecture incorporates a structure-aware contrastive loss that reinforces syntactic consistency and deploys auxiliary classification heads for POS tagging,dependency parsing,and multi-class offensive detection.The classifier for offensive words operates at both sentence and token levels and obtains guidance from syntactic features and formal finite automata rules that model offensive language structures-hate speech,profanity,sarcasm,and threats.Using this architecture,we construct a syntactically enriched,socially annotated corpus.Experimental results show improvements in translation quality,with a BLEU score of 33.5,UAS/LAS parsing accuracies of 92.4%and 90%,and a 4.5%Fl-score gain in offensive content detection compared with baseline POS+DEP+Offense models.Also,the proposed model achieved 92.3%in offensive content neutralization,as confirmed by ablation studies.This comprehensive English-Tamil NMT model that unifies syntactic modelling and ethical filtering-laying the groundwork for applications in social media moderation,hate speech mitigation,and policy-compliant multilingual content generation.展开更多
Understanding the dynamics of vegetation carbon sequestration(VCS)is essential for regional carbon neutrality strategies.This study revealed the spatiotemporal patterns of VCS and its relationship with anthropogenic c...Understanding the dynamics of vegetation carbon sequestration(VCS)is essential for regional carbon neutrality strategies.This study revealed the spatiotemporal patterns of VCS and its relationship with anthropogenic carbon emissions(ACEs)in Shandong Province,China during 2000-2020,and identified the sensitivity factors affecting VCS.The results show that:1)VCS increased consistently from 193.45 million t to 256.41 million t,with high values areas concentrated in the central,northeastern,and southeastern mountainous and hilly regions,while low values were found in water bodies and urban built-up areas.At the city level,Linyi,Yantai,Binzhou,and Jinan experienced the most significant rises-reaching up to 243000 t/yr.At the county level,Pingdu,Qixia,and Yiyuan also showed substantial growth,each exceeding 30400 t/yr.2)Digital Elevation Molde(DEM)was identified as the dominant natural factor influencing VCS distribution,while land use optimization measures,especially afforestation and farmland conversion in sloped terrain,were the primary human drivers of VCS increase.3)Urbanization and carbon neutrality were not mutually exclusive.While urban expansion locally reduced VCS,rural emigration enhanced carbon sinks in surrounding areas,partially offsetting urban losses.This compensatory mechanism supported VCS increases in nearly all cities and 90% of counties.Nevertheless,with ACEs continuing to rise and the offset ratio by VCS declining,achieving carbon neutrality requires regional strategies that integrate with accelerated energy conservation,emission reduction technologies,and energy transition.These findings provide a scientific basis for decomposing carbon neutrality targets across cities and counties in Shandong and a reference for developing localized land use policies in similar regions.展开更多
Energy storage is a key factor in the drive for carbon neutrality and carbon nanotubes(CNTs)may have an important role in this.Their intrinsic sp2 covalent structure gives them excellent electrical conductivity,mechan...Energy storage is a key factor in the drive for carbon neutrality and carbon nanotubes(CNTs)may have an important role in this.Their intrinsic sp2 covalent structure gives them excellent electrical conductivity,mechanical strength,and chemical stability,making them suitable for many uses in energy storage,such as lithium-ion batteries(LIBs).Currently,their use in LIBs mainly focuses on conductive networks,current collectors,and dry electrodes.The review outlines advances in the use of CNTs in the cathodes and anodes of LIBs,especially in the electrode fabrication and mechanical sensors,as well as providing insights into their future development.展开更多
Coal-based soild wastes(CBSWs)are industrial byproducts that can be harmful to the environment.The exploitation and utilization of CBsWs offer societal advantages such as resource conservation,pollution reduction,and ...Coal-based soild wastes(CBSWs)are industrial byproducts that can be harmful to the environment.The exploitation and utilization of CBsWs offer societal advantages such as resource conservation,pollution reduction,and cost-effective production.However,environmentally sustainable management remains a worldwide challenge due to the substantial production volume and limited disposal capacity of CBSWs.The physicochemical properties and utilization of CBSWs are summarized,including fly ash,coal gangue and coal gasification slag.It also presents the current global applications status of CBSWs resources and examines market supply and demand.Subsequently,the paper provides an overview of studies on ways to utilise CBSWs,highlighting the primary avenues of CBSWs resource utilization which are mainly from the fields of chemical materials,metallurgy and agriculture.Furthermore,a comparative evaluation of the various methods for CBSWs resource recovery is conducted,outlining their respective advantages and disadvantages.The future development of CBSWs recycling processes is also discussed.The review concludes that while there is a growing need for attention in CBSWs recycling,its utilization will involve a combination of both large-scale treatment and refinement processes.The paper aims to offer references and insights for the effective utilization and environmental protection of CBSWs.Future direction will focus on the collaborative utilization of CBSWs,emphasizing on the combination of large-scale and high-value utilization.In addition,there is a need to establish a comprehensive database based on on-site production practices,explore on-site solutions to reduce transportation costs,and improve physicochemical properties during the production process.展开更多
Large-scale deployment of carbon dioxide(CO_(2))removal technology is an essential step to cope with global warming and achieve carbon neutrality.Direct air capture(DAC)has recently received increasing attention given...Large-scale deployment of carbon dioxide(CO_(2))removal technology is an essential step to cope with global warming and achieve carbon neutrality.Direct air capture(DAC)has recently received increasing attention given the high flexibility to remove CO_(2)from discrete sources.Porous materials with adjustable pore characteristics are promising sorbents with low or no latent heat of vaporization.This review article has summarized the recent development of porous sorbents for DAC,with a focus of pore engineering strategy and adsorption mechanism.Physisorbents such as zeolites,porous carbons,metal-organic frameworks(MOFs),and amine-modified chemisorbents have been discussed and their challenges in practical application have been analyzed.At last,future directions have been proposed,and it is expected to inspire collaborations from chemistry,environment,material science and engineering communities.展开更多
Carbon Capture,Utilization,and Storage(CCUS)is a crucial technology for achieving carbon neutrality,but it faces significant challenges.Despite substantial investments and policy support,CCUS projects have underperfor...Carbon Capture,Utilization,and Storage(CCUS)is a crucial technology for achieving carbon neutrality,but it faces significant challenges.Despite substantial investments and policy support,CCUS projects have underperformed due to technical difficulties,high costs,and controversies surrounding the fossil fuel industry's involvement.The effectiveness and feasibility of CCUS in reducing carbon emissions remain uncertain.This viewpoint provides a comprehensive analysis of the current state of CCUS technology,examining its potential to reduce carbon emissions,the challenges hindering its deployment,and the strategies needed to overcome these barriers.We discuss the need for a combinatorial approach to unlock CCUS's full potential,and also emphasize the importance of selecting optimal CO_(2)utilization pathways to maximize economic benefits and CO_(2)absorption.Although CCUS faces technical,economic,and social barriers,it can still play a valuable role in mitigating emissions from hard-to-abate sectors when supported by comprehensive strategies and collaborative efforts among governments,industries,and research institutions.By addressing these challenges and investing in innovation,CCUS can contribute to achieving carbon neutrality and building a sustainable,low-carbon future.展开更多
This paper proposes that China,under the challenge of balancing its development and security,can aim for the Paris Agreement's goal to limit global warming to no more than 2℃by actively seeking carbonpeak and car...This paper proposes that China,under the challenge of balancing its development and security,can aim for the Paris Agreement's goal to limit global warming to no more than 2℃by actively seeking carbonpeak and carbon-neutrality pathways that align with China's national conditions,rather than following the idealized path toward the 1.5℃target by initially relying on extensive negative-emission technologies such as direct air carbon capture and storage(DACCS).This work suggests that pursuing a 1.5℃target is increasingly less feasible for China,as it would potentially incur 3–4 times the cost of pursuing the 2℃target.With China being likely to achieve a peak in its emissions around 2028,at about 12.8 billion tonnes of anthropogenic carbon dioxide(CO_(2)),and become carbon neutral,projected global warming levels may be less severe after the 2050s than previously estimated.This could reduce the risk potential of climate tipping points and extreme events,especially considering that the other two major carbon emitters in the world(Europe and North America)have already passed their carbon peaks.While natural carbon sinks will contribute to China's carbon neutrality efforts,they are not expected to be decisive in the transition stages.This research also addresses the growing focus on climate overshoot,tipping points,extreme events,loss and damage,and methane reductions in international climate cooperation,emphasizing the need to balance these issues with China's development,security,and fairness considerations.China's pursuit of carbon neutrality will have significant implications for global emissions scenarios,warming levels,and extreme event projections,as well as for climate change hotspots of international concern,such as climate tipping points,the climate crisis,and the notion that the world has moved from a warming to a boiling era.Possible research recommendations for global emissions scenarios based on China's 2℃target pathway are also summarized.展开更多
Buildings are crucial for achieving carbon reduction and mitigating climate change.China's dual-carbon strategy includes ambitious goals for carbon peaking and carbon neutrality in the building sector.However,clea...Buildings are crucial for achieving carbon reduction and mitigating climate change.China's dual-carbon strategy includes ambitious goals for carbon peaking and carbon neutrality in the building sector.However,clear technical pathways and roadmaps for achieving these objectives remain lacking.In this study,we examined the trajectory and characteristics of energy consumption and emissions in China's building sector and conducted future scenario analyses informed by global comparative studies.Ecological development pathways were proposed as target scenarios to achieve carbon neutrality in the building sector.Detailed pathways to achieve carbon neutrality were delineated,covering various tasks and timelines.These included managing building stocks,improving energy efficiency and sufficiency,promoting electrification,implementing photovoltaic-energy storage-direct current-flexibility(PEDF)buildings,decarbonizing heating systems,and developing new energy systems for rural areas.In addition,we discussed and recommended policy measures to enhance building service provisions within the framework of the ecological development concept and promote key technologies within the context of a low-carbon energy system transition.The findings of this study provide high-level recommendations for policymakers in the building and energy sectors and offer insights into technological perspectives and development targets for future research and engineering practice.展开更多
Solar energy, as a renewable resource, is an effective solution to the current global energy shortage problem. To actively respond to the call for "carbon peak" and "carbon neutrality", solar cell ...Solar energy, as a renewable resource, is an effective solution to the current global energy shortage problem. To actively respond to the call for "carbon peak" and "carbon neutrality", solar cell industry has experienced unprecedented development. The full utilization of solar energy resources remains an urgent issue to be addressed.展开更多
China has pledged to peak carbon dioxide(CO_(2))emissions by 2030 and achieve carbon neutrality by 2060.Carbon capture and storage(CCS)will play a key role in these efforts.Over the past several years,the China Geolog...China has pledged to peak carbon dioxide(CO_(2))emissions by 2030 and achieve carbon neutrality by 2060.Carbon capture and storage(CCS)will play a key role in these efforts.Over the past several years,the China Geological Survey(CGS)has completed the Suitability Evaluation Map of CO_(2)Geological Storage in Main Sedimentary Basins in China and Adjacent Sea Regions in 2017.This map reflects the suitability of the first-and secondary-order tectonic units within sedimentary basins for cO_(2)geological storage for CCS planning.The Junggar Basin is recognized as an important region for future CCS projects.Results from a mesoscale evaluation using the volume method indicate that deep saline aquifers represent the most significant resources for CO_(2)storage,with potential ranging from 48×10^(9)to 164×10^(9)t(with a P50 value of 96×10^(9)t).The highest storage potential is identified in the central and northern parts of the basin,reaching up to 9.5×10^(6)t/km^(2)at the P50 probability level.In contrast,the hinterland,eastern,and western parts of the basin generally exhibit storage potential of below 1.0×10^(6)t/km^(2)at the same probability level.The CGs has also characterized historical CO_(2)plume migration in reservoirs at the storage site of the Shenhua CCS demonstration project and conducted numerical simulations of CO_(2)plume migration for periods of 10 and 20 years following the shutdown of the injection well.The CGS implemented a kiloton-scale pilot test on CO_(2)-enhanced water recovery(CO_(2)-EWR)in eastern Junggar,revealing that CO_(2)flooding can improve the pressure for fluid production,with the highest ratio of CO_(2)to produced fluids estimated at approximately 1.2.Besides,an observation field for natural CO_(2)leakage,covering about 930 m^(2),was built in Qinghai Province.In natural CO_(2)fields or at artificial CO_(2)injection research sites,cO_(2)leakage points are primarily related to the distribution of faults(especially fault crossing),which can serve as pathways for CO_(2)leakage.The observation field provides a natural analog to wellbore failure and offers an opportunity to further monitor CO_(2)geological storage sites.However,it has been inferred that borehole ZK10 at the observation field has become a leakage pathway due to the drilling activities,inadequate well-plugging,and abandonment procedures without considering CO_(2)corrosion.展开更多
CO_(2)capture and utilization(CCU)are two important processes to address the gigaton challenges in reducing greenhouse gas emissions.Given that both processes are energy-intensive,integrating CO_(2)capture and utiliza...CO_(2)capture and utilization(CCU)are two important processes to address the gigaton challenges in reducing greenhouse gas emissions.Given that both processes are energy-intensive,integrating CO_(2)capture and utilization(ICCU)can improve energy efficiency and reduce economic costs by eliminating steps such as CO_(2)concentration,storage,or capture media regeneration.Aiming at building a bridge between theoretical research and practical application,this review promotes the understanding of high-temperature ICCU,mild/low-temperature ICCU,and emerging electro-/photo-driven ICCU.The reaction mechanism and technical bottleneck are comprehensively evaluated,which could provide a perspective on the design principle of dualfunctional materials(DFMs)combining synergetic adsorptive and catalytic sites.On this basis,novel strategies are proposed from the viewpoint of chemical process intensification to strive for a thermodynamics and kinetics matching between the capture and in situ conversion processes.It is expected that this review can stimulate more research in the future involving expanding the product range,fabricating long-term DFMs,developing a workable reactor,optimizing operation conditions,and establishing an industrial demonstration.展开更多
Thermospheric neutral winds(TNWs)refer to the neutral gases in the thermosphere circulating as tides,which play a crucial role in the dynamics of the thermosphere-ionosphere system(TIS).Global geospace neutral winds,p...Thermospheric neutral winds(TNWs)refer to the neutral gases in the thermosphere circulating as tides,which play a crucial role in the dynamics of the thermosphere-ionosphere system(TIS).Global geospace neutral winds,particularly over the magnetic equator,have been a subject of study for several decades.However,despite the known importance of neutral winds,a comprehensive understanding and characterization of the winds is still lacking.Various ground-based and satellite missions have provided valuable information on the contribution of neutral winds to the global atmospheric dynamics.However,efforts in the global monitoring of neutral winds are still lacking,and the drivers behind the behavior of TNWs as well as their influence on the TIS remain incomplete.To address these knowledge gaps in the global circulation of TNWs,it is crucial to develop a deep understanding of the neutral wind characteristics over different regions.The low-latitude equatorial region in particular has been observed to exert complex influences on TNWs because of the unique effects of the Earth’s magnetic field at the dip equator.Studying neutral winds over this region will provide valuable insights into the unique dynamics and processes that occur in this region,thereby enhancing our understanding of their role in the overall dynamics of the TIS.Additionally,through empirical observations,an improved ability to accurately model and predict the behavior of this region can be achieved.This review article addresses challenges in understanding equatorial winds by reviewing historical measurements,current missions,and the interactions of ionospheric and thermospheric phenomena,emphasizing the need for comprehensive measurements to improve global atmospheric dynamics and weather forecasting.展开更多
In this study,ionosonde observations over Fuke(19.5°N,109.1°E),Wuhan(30.5°N,114.4°E),and Mohe(53.5°N,122.3°E)were analyzed to demonstrate the responses of the sporadic E()to the severe at...In this study,ionosonde observations over Fuke(19.5°N,109.1°E),Wuhan(30.5°N,114.4°E),and Mohe(53.5°N,122.3°E)were analyzed to demonstrate the responses of the sporadic E()to the severe atmospheric disturbances caused by the Tonga volcanic eruptions on January 15,2022.The most prominent signature was the disappearance of the layer after~10:00 UT over Wuhan and Fuke,which was attributed to the vertical drift caused by the eruptions.The occurred intermittently after 13:00 UT following the arrival of the tropospheric Lamb wave.To examine the causal mechanism for the intermittence,we also included data of horizontal winds in the mesosphere and lower thermosphere region recorded by the meteor radars at Wuhan and Mohe in this study.The wind disturbances with periods of~20 hours contributed to the formation of the layer in the nighttime on January 15.展开更多
The Michelson Interferometer for Global High-resolution Thermospheric Imaging(MIGHTI)onboard the Ionospheric Connection Explorer(ICON)satellite offers the opportunity to investigate the altitude profile of thermospher...The Michelson Interferometer for Global High-resolution Thermospheric Imaging(MIGHTI)onboard the Ionospheric Connection Explorer(ICON)satellite offers the opportunity to investigate the altitude profile of thermospheric winds.In this study,we used the red-line measurements of MIGHTI to compare with the results estimated by Horizontal Wind Model 14(HWM14).The data selected included both the geomagnetic quiet period(December 2019 to August 2022)and the geomagnetic storm on August 26-28,2021.During the geomagnetic quiet period,the estimations of neutral winds from HWM14 showed relatively good agreement with the observations from ICON.According to the ICON observations,near the equator,zonal winds reverse from westward to eastward at around 06:00 local time(LT)at higher altitudes,and the stronger westward winds appear at later LTs at lower altitudes.At around 16:00 LT,eastward winds at 300 km reverse to westward,and vertical gradients of zonal winds similar to those at sunrise hours can be observed.In the middle latitudes,zonal winds reverse about 2-4 h earlier.Meridional winds vary more significantly than zonal winds with seasonal and latitudinal variations.According to the ICON observations,in the northern low latitudes,vertical reversals of meridional winds are found at 08:00-13:00 LT from 300 to 160 km and at around 18:00 LT from 300 to 200 km during the June solstice.Similar reversals of meridional winds are found at 04:00-07:00 LT from 300 to 160 km and at 22:00-02:00 LT from 270 to 200 km during the December solstice.In the southern low latitudes,meridional wind reversals occur at 08:00-11:00 LT from 200 to 160 km and at 21:00-02:00 LT from 300 to 200 km during the June solstice.During the December solstice,reversals of the meridional wind appear at 20:00-01:00 LT below 200 km and at 06:00-11:00 LT from 300 to 160 km.In the northern middle latitudes,the northward winds are dominant at 08:00-14:00 LT at 230 km during the June solstice.Northward winds persist until 16:00 LT at 160 and 300 km.During the December solstice,the northward winds are dominant from 06:00 to 21:00 LT.The vertical variations in neutral winds during the geomagnetic storm on August 26-28 were analyzed in detail.Both meridional and zonal winds during the active geomagnetic period observed by ICON show distinguishable vertical shear structures at different stages of the storm.On the dayside,during the main phase,the peak velocities of westward winds extend from a higher altitude to a lower altitude,whereas during the recovery phase,the peak velocities of the westward winds extend from lower altitudes to higher altitudes.The velocities of the southward winds are stronger at lower altitudes during the storm.These vertical structures of horizontal winds during the storm could not be reproduced by the HWM14 wind estimations,and the overall response to the storm of the horizontal winds in the low and middle latitudes is underestimated by HWM14.The ICON observations provide a good dataset for improving the HWM wind estimations in the middle and upper atmosphere,especially the vertical variations.展开更多
基金supported by the Natural Science Foundation of China(Grants U2166211)Zhejiang Provincial Natural Science Foundation of China(Grants LY24E070006 and LMS25E070002).
文摘Driven by the global energy transition and the urgent“dual carbon”goals,regional integrated energy system(RIES)planning is undergoing a paradigm shift from carbon reduction to negative carbon emissions.This paper provides a comprehensive review of the theoretical frameworks and technical pathways for RIES planning from a carbon-centric perspective.A key contribution is the proposed Carbon-Energy-Economy(CEE)triple-dimensional governance framework,which endogenizes carbon factors into planning decisions through emission constraints,trading mechanisms,and capture technologies.We first analyze the fundamental characteristics of RIES and their critical role in achieving carbon neutrality,detailing advancements in multi-energy coupling models,energy router concepts,and standardized energy hub modeling.The paper further explores multi-energy flow analysis methods,and systematically compares the applicability and limitations of various planning algorithms,with emphasis on addressing uncertainties from renewable integration.Finally,we highlight the integration of artificial intelligence with traditional optimization methods,offering new pathways for intelligent,adaptive,and low-carbon RIES planning.This review underscores the transition towards data-physical fusion models,cooperative uncertainty optimization,multi-market planning,and innovative zero/negative-carbon technological routes.
基金supported by the National Natural Science Foundation of China(12473085).
文摘The neutral surface of a concave thin mirror is too close to the mirror surface,which makes it difficult to effectively mount the flexible structure and increases the mirror surface shape error.To address this problem,we design a flexible support structure including connectors,a support plate,and flexible structures,and construct an equivalent mirror by installing connectors and a support plate on the back of the mirror.While ensuring that the neutral surface of the equivalent mirror is moved away from the mirror surface,we optimize the support structure so that the rotary center of the flexible structure is located on the neutral surface of the equivalent mirror,avoiding the tilting moment.Following design and modeling of the structure,we analyze the static and dynamic characteristics using a finite element simulation,finding a root-mean-square(RMS)value for the surface shape error of 9.28 nm under the coupled effects of 1g gravity load,4℃ temperature rise,and 0.005 mm unevenness assembly error,with a fundamental frequency of 170.75 Hz,which all meet the design requirements.Finally,we carry out a surface shape error test of the mirror assembly,confirming it to meet the design index requirement of the mirror assembly.Simulation and test results verify the reliability and effectiveness of our proposed support structure.
基金financially supported by National Natural Science Foundation of China(22466010)Guizhou Provincial Basic Research Program(Natural Science)ZK[2023]47 and key program ZD[2025]075+6 种基金Innovation and Entrepreneurship Project for overseas Talents in Guizhou Province[2022]02Specific Natural Science Foundation of Guizhou University(X202207)the national undergraduate innovation and entrepreneurship training program(gzugc2023006gzusc2024012)SRT project of Guizhou university(2023SRT0292023SRT024)supported by Shanghai Technical Service Center of Science and Engineering Computing,Shanghai University。
文摘Electrocatalytic nitrate reduction reaction(NO3RR)represents a sustainable and environmentally benign route for ammonia(NH3)synthesis.However,NO3RR is still limited by the competition from hydrogen evolution reaction(HER)and the high energy barrier in the hydrogenation step of nitrogen-containing intermediates.Here,we report a selective etching strategy to construct Ru M nanoalloys(M=Fe,Co,Ni,Cu)uniformly dispersed on porous nitrogen-doped carbon substrates for efficient neutral NH3electrosynthesis.Density functional theory calculations confirm that the synergic effect between Ru and transition metal M modulates the electronic structure of the alloy,significantly lowering the energy barrier for the conversion of*NO_(2)to*HNO_(2).Experimentally,the optimized Ru Fe-NC catalyst achieves 100%Faraday efficiency with a high yield rate of 0.83 mg h^(-1)mg^(-1)catat a low potential of-0.1 V vs.RHE,outperforming most reported catalysts.In situ spectroscopic analyses further demonstrate that the Ru M-NC effectively promotes the hydrogenation of nitrogen intermediates while inhibiting the formation of hydrogen radicals,thereby reducing HER competition.The Ru FeNC assembled Zn-NO_(3)^(-)battery achieved a high open-circuit voltage and an outstanding power density and capacity,which drive selective NO_(3)^(-)conversion to NH3.This work provides a powerful synergistic design strategy for efficient NH3electrosynthesis and a general framework for the development of advanced multi-component catalysts for sustainable nitrogen conversion.
基金funded by the National Natural Science Foundation of China(Grant No.42275039)the Meteorological Joint Fund by NSF and CMA(Grant No.U2342224)+1 种基金the National Key R&D Program of China(Grant No.2022YFC3701202)the S&T Development Fund of CAMS(Grant No.2024KJ019)。
文摘Global land monsoon precipitation(GLMP)is highly sensitive to changes in interhemispheric thermal contrast(ITC).Amplified interhemispheric asymmetries of GLMP due to enhanced ITC driven by high-level anthropogenic emissions are expected to simultaneously increase the probability of regional floods and droughts,threatening ecosystems within global terrestrial monsoon regions and the freshwater supply for billions of residents in these areas.In this study,the responses of GLMP to the evolution of ITC toward the carbon neutrality goal are assessed using multimodel outputs from a new model intercomparison project(CovidMIP).The results show that the Northern Hemisphere-Southern Hemisphere(NH-SH)asymmetry of GLMP in boreal summer weakens during the 2040s,as a persistent reduction in well-mixed greenhouse gas(WMGHG)emissions leads to a downward trend in the ITC after 2040.At the same time,the reduction in WMGHG emissions dampens the Eastern Hemisphere-Western Hemisphere(EH-WH)asymmetry of GLMP by inducing La Niña-like cooling and enhancing moisture transport to Inner America.The resulting increases in land monsoon precipitation(LMP)may alleviate drought under the global warming scenario by about 19%-25%and 7%-9%in the WH and SH monsoon regions,respectively.However,a persistent reduction in aerosol emissions in Asia will dominate the increases in LMP in this region until the mid-21st century,and these increases may be approximately 23%-60%of the growth under the global warming scenario.Our results highlight the different rates of response of aerosol and WMGHG concentrations to the carbon neutrality goal,leading to various changes in LMP at global and regional scales.
基金supported by the National Natural Science Foundation of China(22341602,U24B20195)。
文摘Nuclear energy is critical not only to sustainable economic development but also to achieving peaking carbon dioxide emissions and carbon neutrality[1].China is expected to host the world’s largest number of nuclear power plants in a few years.Uranium-235 serves as the primary fissile material for the fabrication of nuclear fuel.However,there are only about 6.14 million tons of uranium resources on land,which can sustain~70 years of operation for global nuclear power plants.Thereby,the recovery of uranium from spent fuel,radioactive waste solutions,seawater,and salt lakes is crucial for the healthy development of nuclear power utilization[2-4].
文摘When performing English-to-Tamil Neural Machine Translation(NMT),end users face several challenges due to Tamil's rich morphology,free word order,and limited annotated corpora.Although available transformer-based models offer strong baselines,they compromise syntactic awareness and the detection and man-agement of offensive content in cluttered,noisy,and informal text.In this paper,we present POSDEP-Offense-Trans,a multi-task NMT framework that combines Part-of-Speech(POS)and Dependency Parsing(DEP)methods with a robust offensive language classification module.Our architecture enriches the Transformer encoder with syntax-aware embeddings and provides syntax-guided attention mechanisms.The architecture incorporates a structure-aware contrastive loss that reinforces syntactic consistency and deploys auxiliary classification heads for POS tagging,dependency parsing,and multi-class offensive detection.The classifier for offensive words operates at both sentence and token levels and obtains guidance from syntactic features and formal finite automata rules that model offensive language structures-hate speech,profanity,sarcasm,and threats.Using this architecture,we construct a syntactically enriched,socially annotated corpus.Experimental results show improvements in translation quality,with a BLEU score of 33.5,UAS/LAS parsing accuracies of 92.4%and 90%,and a 4.5%Fl-score gain in offensive content detection compared with baseline POS+DEP+Offense models.Also,the proposed model achieved 92.3%in offensive content neutralization,as confirmed by ablation studies.This comprehensive English-Tamil NMT model that unifies syntactic modelling and ethical filtering-laying the groundwork for applications in social media moderation,hate speech mitigation,and policy-compliant multilingual content generation.
基金Under the auspices of the National Natural Science Foundation of China(No.42476247,42461015)the Open Research Fund of Key Laboratory of Coastal Science and Integrated Management,Ministry of Natural Resources(No.2024COSIM01)Guangxi Science and Technology Base and Talent Special Project(No.GuikeAD23026194)。
文摘Understanding the dynamics of vegetation carbon sequestration(VCS)is essential for regional carbon neutrality strategies.This study revealed the spatiotemporal patterns of VCS and its relationship with anthropogenic carbon emissions(ACEs)in Shandong Province,China during 2000-2020,and identified the sensitivity factors affecting VCS.The results show that:1)VCS increased consistently from 193.45 million t to 256.41 million t,with high values areas concentrated in the central,northeastern,and southeastern mountainous and hilly regions,while low values were found in water bodies and urban built-up areas.At the city level,Linyi,Yantai,Binzhou,and Jinan experienced the most significant rises-reaching up to 243000 t/yr.At the county level,Pingdu,Qixia,and Yiyuan also showed substantial growth,each exceeding 30400 t/yr.2)Digital Elevation Molde(DEM)was identified as the dominant natural factor influencing VCS distribution,while land use optimization measures,especially afforestation and farmland conversion in sloped terrain,were the primary human drivers of VCS increase.3)Urbanization and carbon neutrality were not mutually exclusive.While urban expansion locally reduced VCS,rural emigration enhanced carbon sinks in surrounding areas,partially offsetting urban losses.This compensatory mechanism supported VCS increases in nearly all cities and 90% of counties.Nevertheless,with ACEs continuing to rise and the offset ratio by VCS declining,achieving carbon neutrality requires regional strategies that integrate with accelerated energy conservation,emission reduction technologies,and energy transition.These findings provide a scientific basis for decomposing carbon neutrality targets across cities and counties in Shandong and a reference for developing localized land use policies in similar regions.
文摘Energy storage is a key factor in the drive for carbon neutrality and carbon nanotubes(CNTs)may have an important role in this.Their intrinsic sp2 covalent structure gives them excellent electrical conductivity,mechanical strength,and chemical stability,making them suitable for many uses in energy storage,such as lithium-ion batteries(LIBs).Currently,their use in LIBs mainly focuses on conductive networks,current collectors,and dry electrodes.The review outlines advances in the use of CNTs in the cathodes and anodes of LIBs,especially in the electrode fabrication and mechanical sensors,as well as providing insights into their future development.
基金supported by the following:“National Natural Science Foundation of China”(22478231)“Natural Science Foundation of Henan”(242300421449)“Fundamental Research Program of Shanxi Province”(202403021221011).
文摘Coal-based soild wastes(CBSWs)are industrial byproducts that can be harmful to the environment.The exploitation and utilization of CBsWs offer societal advantages such as resource conservation,pollution reduction,and cost-effective production.However,environmentally sustainable management remains a worldwide challenge due to the substantial production volume and limited disposal capacity of CBSWs.The physicochemical properties and utilization of CBSWs are summarized,including fly ash,coal gangue and coal gasification slag.It also presents the current global applications status of CBSWs resources and examines market supply and demand.Subsequently,the paper provides an overview of studies on ways to utilise CBSWs,highlighting the primary avenues of CBSWs resource utilization which are mainly from the fields of chemical materials,metallurgy and agriculture.Furthermore,a comparative evaluation of the various methods for CBSWs resource recovery is conducted,outlining their respective advantages and disadvantages.The future development of CBSWs recycling processes is also discussed.The review concludes that while there is a growing need for attention in CBSWs recycling,its utilization will involve a combination of both large-scale treatment and refinement processes.The paper aims to offer references and insights for the effective utilization and environmental protection of CBSWs.Future direction will focus on the collaborative utilization of CBSWs,emphasizing on the combination of large-scale and high-value utilization.In addition,there is a need to establish a comprehensive database based on on-site production practices,explore on-site solutions to reduce transportation costs,and improve physicochemical properties during the production process.
基金financial support from the National Natural Science Foundation of China(Nos.22278011,22225803,22038001 and 22108007)Beijing Natural Science Foundation(No.Z230023)+1 种基金The Science&Technology Project of Beijing Municipal Education Committee(No.KZ201810005004)Beijing Nova Program(No.Z211100002121094)。
文摘Large-scale deployment of carbon dioxide(CO_(2))removal technology is an essential step to cope with global warming and achieve carbon neutrality.Direct air capture(DAC)has recently received increasing attention given the high flexibility to remove CO_(2)from discrete sources.Porous materials with adjustable pore characteristics are promising sorbents with low or no latent heat of vaporization.This review article has summarized the recent development of porous sorbents for DAC,with a focus of pore engineering strategy and adsorption mechanism.Physisorbents such as zeolites,porous carbons,metal-organic frameworks(MOFs),and amine-modified chemisorbents have been discussed and their challenges in practical application have been analyzed.At last,future directions have been proposed,and it is expected to inspire collaborations from chemistry,environment,material science and engineering communities.
基金funding from the National Natural Science Foundation of China(62074123)Key Research and Development Plan of Shaanxi Province(No.2024GXZDCYL-01-06)China National Petroleum Corporation(CNPC)Basic Research and Strategic Reserve Technology Research Fund Project(No.2023DQ03-26).
文摘Carbon Capture,Utilization,and Storage(CCUS)is a crucial technology for achieving carbon neutrality,but it faces significant challenges.Despite substantial investments and policy support,CCUS projects have underperformed due to technical difficulties,high costs,and controversies surrounding the fossil fuel industry's involvement.The effectiveness and feasibility of CCUS in reducing carbon emissions remain uncertain.This viewpoint provides a comprehensive analysis of the current state of CCUS technology,examining its potential to reduce carbon emissions,the challenges hindering its deployment,and the strategies needed to overcome these barriers.We discuss the need for a combinatorial approach to unlock CCUS's full potential,and also emphasize the importance of selecting optimal CO_(2)utilization pathways to maximize economic benefits and CO_(2)absorption.Although CCUS faces technical,economic,and social barriers,it can still play a valuable role in mitigating emissions from hard-to-abate sectors when supported by comprehensive strategies and collaborative efforts among governments,industries,and research institutions.By addressing these challenges and investing in innovation,CCUS can contribute to achieving carbon neutrality and building a sustainable,low-carbon future.
基金supported by the top-level design of the National Natural Science Foundation of China(NSFC)Major Project“Realization of optimal carbon neutral pathway and coupling of multi-scale interaction patterns of natural-social systems in China”(42341202)the Basic Scientific Research Fund of the Chinese Academy of Meteorological Sciences(2021Z014)。
文摘This paper proposes that China,under the challenge of balancing its development and security,can aim for the Paris Agreement's goal to limit global warming to no more than 2℃by actively seeking carbonpeak and carbon-neutrality pathways that align with China's national conditions,rather than following the idealized path toward the 1.5℃target by initially relying on extensive negative-emission technologies such as direct air carbon capture and storage(DACCS).This work suggests that pursuing a 1.5℃target is increasingly less feasible for China,as it would potentially incur 3–4 times the cost of pursuing the 2℃target.With China being likely to achieve a peak in its emissions around 2028,at about 12.8 billion tonnes of anthropogenic carbon dioxide(CO_(2)),and become carbon neutral,projected global warming levels may be less severe after the 2050s than previously estimated.This could reduce the risk potential of climate tipping points and extreme events,especially considering that the other two major carbon emitters in the world(Europe and North America)have already passed their carbon peaks.While natural carbon sinks will contribute to China's carbon neutrality efforts,they are not expected to be decisive in the transition stages.This research also addresses the growing focus on climate overshoot,tipping points,extreme events,loss and damage,and methane reductions in international climate cooperation,emphasizing the need to balance these issues with China's development,security,and fairness considerations.China's pursuit of carbon neutrality will have significant implications for global emissions scenarios,warming levels,and extreme event projections,as well as for climate change hotspots of international concern,such as climate tipping points,the climate crisis,and the notion that the world has moved from a warming to a boiling era.Possible research recommendations for global emissions scenarios based on China's 2℃target pathway are also summarized.
基金supported by the National Natural Science Foundation of China(52478095 and 72261147760)the Chinese Academy of Engineering Project"Low-Carbon Transition Strategy and Pathways for Urban and Rural Energy Supply Systems in China"(2023-XBZD-07)the China Postdoctoral Science Foundation(GZC20240874)。
文摘Buildings are crucial for achieving carbon reduction and mitigating climate change.China's dual-carbon strategy includes ambitious goals for carbon peaking and carbon neutrality in the building sector.However,clear technical pathways and roadmaps for achieving these objectives remain lacking.In this study,we examined the trajectory and characteristics of energy consumption and emissions in China's building sector and conducted future scenario analyses informed by global comparative studies.Ecological development pathways were proposed as target scenarios to achieve carbon neutrality in the building sector.Detailed pathways to achieve carbon neutrality were delineated,covering various tasks and timelines.These included managing building stocks,improving energy efficiency and sufficiency,promoting electrification,implementing photovoltaic-energy storage-direct current-flexibility(PEDF)buildings,decarbonizing heating systems,and developing new energy systems for rural areas.In addition,we discussed and recommended policy measures to enhance building service provisions within the framework of the ecological development concept and promote key technologies within the context of a low-carbon energy system transition.The findings of this study provide high-level recommendations for policymakers in the building and energy sectors and offer insights into technological perspectives and development targets for future research and engineering practice.
文摘Solar energy, as a renewable resource, is an effective solution to the current global energy shortage problem. To actively respond to the call for "carbon peak" and "carbon neutrality", solar cell industry has experienced unprecedented development. The full utilization of solar energy resources remains an urgent issue to be addressed.
基金funded by the National Natural Science Foundation of China(No.42141013)China Geological Survey(DD20221818,DD20242513).
文摘China has pledged to peak carbon dioxide(CO_(2))emissions by 2030 and achieve carbon neutrality by 2060.Carbon capture and storage(CCS)will play a key role in these efforts.Over the past several years,the China Geological Survey(CGS)has completed the Suitability Evaluation Map of CO_(2)Geological Storage in Main Sedimentary Basins in China and Adjacent Sea Regions in 2017.This map reflects the suitability of the first-and secondary-order tectonic units within sedimentary basins for cO_(2)geological storage for CCS planning.The Junggar Basin is recognized as an important region for future CCS projects.Results from a mesoscale evaluation using the volume method indicate that deep saline aquifers represent the most significant resources for CO_(2)storage,with potential ranging from 48×10^(9)to 164×10^(9)t(with a P50 value of 96×10^(9)t).The highest storage potential is identified in the central and northern parts of the basin,reaching up to 9.5×10^(6)t/km^(2)at the P50 probability level.In contrast,the hinterland,eastern,and western parts of the basin generally exhibit storage potential of below 1.0×10^(6)t/km^(2)at the same probability level.The CGs has also characterized historical CO_(2)plume migration in reservoirs at the storage site of the Shenhua CCS demonstration project and conducted numerical simulations of CO_(2)plume migration for periods of 10 and 20 years following the shutdown of the injection well.The CGS implemented a kiloton-scale pilot test on CO_(2)-enhanced water recovery(CO_(2)-EWR)in eastern Junggar,revealing that CO_(2)flooding can improve the pressure for fluid production,with the highest ratio of CO_(2)to produced fluids estimated at approximately 1.2.Besides,an observation field for natural CO_(2)leakage,covering about 930 m^(2),was built in Qinghai Province.In natural CO_(2)fields or at artificial CO_(2)injection research sites,cO_(2)leakage points are primarily related to the distribution of faults(especially fault crossing),which can serve as pathways for CO_(2)leakage.The observation field provides a natural analog to wellbore failure and offers an opportunity to further monitor CO_(2)geological storage sites.However,it has been inferred that borehole ZK10 at the observation field has become a leakage pathway due to the drilling activities,inadequate well-plugging,and abandonment procedures without considering CO_(2)corrosion.
基金supported by the National Natural Science Foundation(22478016,22288102).
文摘CO_(2)capture and utilization(CCU)are two important processes to address the gigaton challenges in reducing greenhouse gas emissions.Given that both processes are energy-intensive,integrating CO_(2)capture and utilization(ICCU)can improve energy efficiency and reduce economic costs by eliminating steps such as CO_(2)concentration,storage,or capture media regeneration.Aiming at building a bridge between theoretical research and practical application,this review promotes the understanding of high-temperature ICCU,mild/low-temperature ICCU,and emerging electro-/photo-driven ICCU.The reaction mechanism and technical bottleneck are comprehensively evaluated,which could provide a perspective on the design principle of dualfunctional materials(DFMs)combining synergetic adsorptive and catalytic sites.On this basis,novel strategies are proposed from the viewpoint of chemical process intensification to strive for a thermodynamics and kinetics matching between the capture and in situ conversion processes.It is expected that this review can stimulate more research in the future involving expanding the product range,fabricating long-term DFMs,developing a workable reactor,optimizing operation conditions,and establishing an industrial demonstration.
基金the Ministry of Higher Education(KPT)Malaysia for the MyBrainSc program.Idahwati Sarudin was supported by Universiti Sains Malaysia through a Short-Term Grant(Project No.304/PFIZIK/6315730)Nurul Shazana Abdul Hamid received funding from Universiti Kebangsaan Malaysia for funding this work through a University Research Grant(Grant No.GUP-2023-048)。
文摘Thermospheric neutral winds(TNWs)refer to the neutral gases in the thermosphere circulating as tides,which play a crucial role in the dynamics of the thermosphere-ionosphere system(TIS).Global geospace neutral winds,particularly over the magnetic equator,have been a subject of study for several decades.However,despite the known importance of neutral winds,a comprehensive understanding and characterization of the winds is still lacking.Various ground-based and satellite missions have provided valuable information on the contribution of neutral winds to the global atmospheric dynamics.However,efforts in the global monitoring of neutral winds are still lacking,and the drivers behind the behavior of TNWs as well as their influence on the TIS remain incomplete.To address these knowledge gaps in the global circulation of TNWs,it is crucial to develop a deep understanding of the neutral wind characteristics over different regions.The low-latitude equatorial region in particular has been observed to exert complex influences on TNWs because of the unique effects of the Earth’s magnetic field at the dip equator.Studying neutral winds over this region will provide valuable insights into the unique dynamics and processes that occur in this region,thereby enhancing our understanding of their role in the overall dynamics of the TIS.Additionally,through empirical observations,an improved ability to accurately model and predict the behavior of this region can be achieved.This review article addresses challenges in understanding equatorial winds by reviewing historical measurements,current missions,and the interactions of ionospheric and thermospheric phenomena,emphasizing the need for comprehensive measurements to improve global atmospheric dynamics and weather forecasting.
基金the Funds of the National Natural Science Foundation of China(NSFC),grant numbers 42174211,42230207,and U2039205.
文摘In this study,ionosonde observations over Fuke(19.5°N,109.1°E),Wuhan(30.5°N,114.4°E),and Mohe(53.5°N,122.3°E)were analyzed to demonstrate the responses of the sporadic E()to the severe atmospheric disturbances caused by the Tonga volcanic eruptions on January 15,2022.The most prominent signature was the disappearance of the layer after~10:00 UT over Wuhan and Fuke,which was attributed to the vertical drift caused by the eruptions.The occurred intermittently after 13:00 UT following the arrival of the tropospheric Lamb wave.To examine the causal mechanism for the intermittence,we also included data of horizontal winds in the mesosphere and lower thermosphere region recorded by the meteor radars at Wuhan and Mohe in this study.The wind disturbances with periods of~20 hours contributed to the formation of the layer in the nighttime on January 15.
基金supported by the National Key R&D Program of China (Grant No.2022YFF0503700)the special funds of Hubei Luojia Laboratory (Grant No.220100011)+1 种基金supported by the International Space Science Institute–Beijing(ISSI-BJ) project“The Electromagnetic Data Validation and Scientific Application Research based on CSES Satellite”and ISSI/ISSI-BJ project,“Multi-Scale Magnetosphere–Ionosphere–Thermosphere Interaction.”
文摘The Michelson Interferometer for Global High-resolution Thermospheric Imaging(MIGHTI)onboard the Ionospheric Connection Explorer(ICON)satellite offers the opportunity to investigate the altitude profile of thermospheric winds.In this study,we used the red-line measurements of MIGHTI to compare with the results estimated by Horizontal Wind Model 14(HWM14).The data selected included both the geomagnetic quiet period(December 2019 to August 2022)and the geomagnetic storm on August 26-28,2021.During the geomagnetic quiet period,the estimations of neutral winds from HWM14 showed relatively good agreement with the observations from ICON.According to the ICON observations,near the equator,zonal winds reverse from westward to eastward at around 06:00 local time(LT)at higher altitudes,and the stronger westward winds appear at later LTs at lower altitudes.At around 16:00 LT,eastward winds at 300 km reverse to westward,and vertical gradients of zonal winds similar to those at sunrise hours can be observed.In the middle latitudes,zonal winds reverse about 2-4 h earlier.Meridional winds vary more significantly than zonal winds with seasonal and latitudinal variations.According to the ICON observations,in the northern low latitudes,vertical reversals of meridional winds are found at 08:00-13:00 LT from 300 to 160 km and at around 18:00 LT from 300 to 200 km during the June solstice.Similar reversals of meridional winds are found at 04:00-07:00 LT from 300 to 160 km and at 22:00-02:00 LT from 270 to 200 km during the December solstice.In the southern low latitudes,meridional wind reversals occur at 08:00-11:00 LT from 200 to 160 km and at 21:00-02:00 LT from 300 to 200 km during the June solstice.During the December solstice,reversals of the meridional wind appear at 20:00-01:00 LT below 200 km and at 06:00-11:00 LT from 300 to 160 km.In the northern middle latitudes,the northward winds are dominant at 08:00-14:00 LT at 230 km during the June solstice.Northward winds persist until 16:00 LT at 160 and 300 km.During the December solstice,the northward winds are dominant from 06:00 to 21:00 LT.The vertical variations in neutral winds during the geomagnetic storm on August 26-28 were analyzed in detail.Both meridional and zonal winds during the active geomagnetic period observed by ICON show distinguishable vertical shear structures at different stages of the storm.On the dayside,during the main phase,the peak velocities of westward winds extend from a higher altitude to a lower altitude,whereas during the recovery phase,the peak velocities of the westward winds extend from lower altitudes to higher altitudes.The velocities of the southward winds are stronger at lower altitudes during the storm.These vertical structures of horizontal winds during the storm could not be reproduced by the HWM14 wind estimations,and the overall response to the storm of the horizontal winds in the low and middle latitudes is underestimated by HWM14.The ICON observations provide a good dataset for improving the HWM wind estimations in the middle and upper atmosphere,especially the vertical variations.
