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The Global Energy and Water Exchanges(GEWEX)Project in Central Asia:The Case for a Regional Hydroclimate Project
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作者 Michael BRODY Maksim KULIKOV +1 位作者 Sagynbek ORUNBAEV Peter J.VAN OEVELEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期777-783,共7页
Central Asia consists of the former Soviet Republics,Kazakhstan,Kyrgyz Republic,Tajikistan,Turkmenistan,and Uzbekistan.The region’s climate is continental,mostly semi-arid to arid.Agriculture is a significant part of... Central Asia consists of the former Soviet Republics,Kazakhstan,Kyrgyz Republic,Tajikistan,Turkmenistan,and Uzbekistan.The region’s climate is continental,mostly semi-arid to arid.Agriculture is a significant part of the region’s economy.By its nature of intensive water use,agriculture is extremely vulnerable to climate change.Population growth and irrigation development have significantly increased the demand for water in the region.Major climate change issues include melting glaciers and a shrinking snowpack,which are the foundation of the region’s water resources,and a changing precipitation regime.Most glaciers are located in Kyrgyzstan and Tajikistan,leading to transboundary water resource issues.Summer already has extremely high temperatures.Analyses indicate that Central Asia has been warming and precipitation might be increasing.The warming is expected to increase,but its spatial and temporal distribution depends upon specific global scenarios.Projections of future precipitation show significant uncertainties in type,amount,and distribution.Regional Hydroclimate Projects(RHPs)are an approach to studying these issues.Initial steps to develop an RHP began in 2021 with a widely distributed online survey about these climate issues.It was followed up with an online workshop and then,in 2023,an in-person workshop,held in Tashkent,Uzbekistan.Priorities for the Global Energy and Water Exchanges(GEWEX)project for the region include both observations and modeling,as well as development of better and additional precipitation observations,all of which are topics for the next workshop.A well-designed RHP should lead to reductions in critical climate uncertainties in policy-relevant timeframes that can influence decisions on necessary investments in climate adaptation. 展开更多
关键词 GEWEX Central Asia climate change AGRICULTURE
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Changes in the Boreal Summer Intraseasonal Oscillation under Global Warming in CMIP6 Models
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作者 Zhefan GAO Chaoxia YUAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期1984-1998,共15页
Changes in the activities of the Boreal Summer Intraseasonal Oscillation(BSISO)at the end of 21st century under the SSP5-8.5 scenario are assessed by adopting 17 CMIP6 models and the weak-temperature-gradient assumpti... Changes in the activities of the Boreal Summer Intraseasonal Oscillation(BSISO)at the end of 21st century under the SSP5-8.5 scenario are assessed by adopting 17 CMIP6 models and the weak-temperature-gradient assumption.Results show that the intraseasonal variations become more structured.The BSISO-related precipitation anomaly shows a larger zonal scale and propagates further northward.However,there is no broad agreement among models on the changes in the eastward and northward propagation speeds and the frequency of individual phases.In the western North Pacific(WNP),the BSISO precipitation variance is significantly increased,at 4.62%K^(−1),due to the significantly increased efficiency of vertical moisture transport per unit of BSISO apparent heating.The vertical velocity variance is significantly decreased,at−3.51%K^(−1),in the middle troposphere,due to the significantly increased mean-state static stability.Changes in the lower-level zonal wind variance are relatively complex,with a significant increase stretching from the northwestern to southeastern WNP,but the opposite in other regions.This is probably due to the combined impacts of the northeastward shift of the BSISO signals and the reduced BSISO vertical velocity variance under global warming.Changes in strong and normal BSISO events in the WNP are also compared.They show same-signed changes in precipitation and large-scale circulation anomalies but opposite changes in the vertical velocity anomalies.This is probably because the precipitation anomaly of strong(normal)events changes at a rate much larger(smaller)than that of the meanstate static stability,causing enhanced(reduced)vertical motion. 展开更多
关键词 Boreal Summer Intraseasonal Oscillation global warming CMIP6 weak-temperature-gradient assumption
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Changes of China’s Status in the Global System and Its Influencing Factors:A Multiple Contact Networks Perspective
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作者 LIU Jian LIU Jibin +2 位作者 YANG Qingshan CAI Sikai LIU Jie 《Chinese Geographical Science》 SCIE CSCD 2024年第2期265-279,共15页
Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on cou... Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on country comparisons or institutional en-vironment.In today’s networked era in which the global economy,trade,personnel,and information are closely connected,studies on China’s global position and its status changes and influencing factors in multiple contact networks are still insufficient.In this study,from the perspective of diverse global contact networks,we constructed economic,cultural,and political influence indices to explore the changes and influencing factors on China’s status in the global system from 2005 to 2018.The results show that during the study period,China’s global influence in the fields of economic ties,cultural exchanges,and political contacts increased significantly,but its influ-ence in the fields of cultural exchanges and political contacts lagged far economic ties.The pattern of China’s economic influence on various economies around the world has shown a transformation from an‘upright pyramid’to an‘inverted pyramid’structure.The proportion of these economies in low-influence zones has decreased from more than 60%in 2005 to less than 20%in 2018.China’s cultural and political influence on various economies around the world has increased significantly;however,for the former,the percentage of high-influence areas is still less than 20%,whereas for the latter the percentage of these economies in medium-and high-influence areas is still less than 50%.Analyses such as a scatter plot matrix show that geographical proximity,economic globalization,close cooperation with developing countries,and a proactive and peaceful foreign policy are important factors in improving China’s status in the diverse global network system. 展开更多
关键词 global system economic ties cultural exchanges political contacts multiple contact networks China’s status
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The Transformation of Economic Globalization and China’s Role in It Under Profound Changes Unseen in a Century
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作者 Chen Jianqi 《Contemporary World》 2024年第3期8-13,共6页
The world economy prospers when it is open,but declines when it is closed.Since the end of the cold war,economic globalization has developed rapidly,forming a new global development pattern that features intertwined i... The world economy prospers when it is open,but declines when it is closed.Since the end of the cold war,economic globalization has developed rapidly,forming a new global development pattern that features intertwined interests of countries all over the world.The report to the 20th National Congress of CPC pointed out that at present,changes in the world,times and history are unfolding in a way unseen in the past. 展开更多
关键词 TRANSFORMATION globalIZATION pattern
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Oruxmaps软件结合Global Mapper软件在矿产资源行业并购中的应用
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作者 赵辉 张国志 《矿产与地质》 2024年第3期578-582,共5页
纸质地质图结合手持GPS,采用手工方式野外记录的传统地质调查工作方式已不能适应数字化和信息化的要求,在矿产资源并购项目中,运用Oruxmaps、Global Mapper等软件,可以制作适应地质调查工作所特需的离线地质图,实现地质图、GPS定位、路... 纸质地质图结合手持GPS,采用手工方式野外记录的传统地质调查工作方式已不能适应数字化和信息化的要求,在矿产资源并购项目中,运用Oruxmaps、Global Mapper等软件,可以制作适应地质调查工作所特需的离线地质图,实现地质图、GPS定位、路线轨迹记录、文字记录、影像记录等的有机结合,形成了一套行之有效的工作流程,极大地提高了路线地质调查工作的质量和效率。 展开更多
关键词 Oruxmaps global Mapper 矿产资源并购项目 离线地质图 路线地质调查
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Global Mapper在水库库容计算及淤积分析中的应用研究
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作者 朱晓江 《城市勘测》 2024年第4期61-64,共4页
基于快捷精准计算水库库容,并与原始库容对比分析库容淤积的目的,使用Global Mapper软件的库容计算和DEM叠加分析功能,通过水库库容复核工程实例进行应用试验,结果表明使用Global Mapper计算库容的结果精度与等高线法的库容结果相当,计... 基于快捷精准计算水库库容,并与原始库容对比分析库容淤积的目的,使用Global Mapper软件的库容计算和DEM叠加分析功能,通过水库库容复核工程实例进行应用试验,结果表明使用Global Mapper计算库容的结果精度与等高线法的库容结果相当,计算高效、结果可靠,DEM叠加分析成果可以直观展示库容淤积分布,有助于为管理单位冲淤冲沙提供决策。 展开更多
关键词 global Mapper 库容计算 DEM 淤积分析
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El Niño and the AMO Sparked the Astonishingly Large Margin of Warming in the Global Mean Surface Temperature in 2023 被引量:2
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作者 Kexin LI Fei ZHENG +1 位作者 Jiang ZHU Qing-Cun ZENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1017-1022,共6页
In 2023,the majority of the Earth witnessed its warmest boreal summer and autumn since 1850.Whether 2023 will indeed turn out to be the warmest year on record and what caused the astonishingly large margin of warming ... In 2023,the majority of the Earth witnessed its warmest boreal summer and autumn since 1850.Whether 2023 will indeed turn out to be the warmest year on record and what caused the astonishingly large margin of warming has become one of the hottest topics in the scientific community and is closely connected to the future development of human society.We analyzed the monthly varying global mean surface temperature(GMST)in 2023 and found that the globe,the land,and the oceans in 2023 all exhibit extraordinary warming,which is distinct from any previous year in recorded history.Based on the GMST statistical ensemble prediction model developed at the Institute of Atmospheric Physics,the GMST in 2023 is predicted to be 1.41℃±0.07℃,which will certainly surpass that in 2016 as the warmest year since 1850,and is approaching the 1.5℃ global warming threshold.Compared to 2022,the GMST in 2023 will increase by 0.24℃,with 88%of the increment contributed by the annual variability as mostly affected by El Niño.Moreover,the multidecadal variability related to the Atlantic Multidecadal Oscillation(AMO)in 2023 also provided an important warming background for sparking the GMST rise.As a result,the GMST in 2023 is projected to be 1.15℃±0.07℃,with only a 0.02℃ increment,if the effects of natural variability—including El Niño and the AMO—are eliminated and only the global warming trend is considered. 展开更多
关键词 record-breaking temperature global mean surface temperature El Niño AMO global warming
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‘Partly'globalized networks and driving mechanism in resource-based state-owned enterprises:A case study of J Group 被引量:1
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作者 Jing Xu Yongchun Yang +1 位作者 Yongjiao Zhang Shan Man 《Geography and Sustainability》 CSCD 2024年第1期77-88,共12页
In the context of economic globalization,while multinational enterprises from developed countries occupy a high-end position in the global value chain,enterprises from developing countries are often marginalized in th... In the context of economic globalization,while multinational enterprises from developed countries occupy a high-end position in the global value chain,enterprises from developing countries are often marginalized in the world market.In China,resource-based state-owned enterprises(SOEs)are tasked with the mission of safeguarding resource security,and their internationalization development ideas and strategic deployment are significantly and fundamentally different from those of other non-state-owned enterprises and large multinational corporations.This study provides ideas for the globalization policies of enterprises in developing countries.We consider J Group in western China as a case and discuss its productive investment and global production network development from 2010 to 2019.We found that J Group was‘Partly'globalized,and there are multiple core nodes with the characteristics of centralized and decentralized coexistence in the production network;in addition,the overall layout centre shifted to Southeast Asia and China;however,its global production was restricted by the enterprise's investment security considerations,support and restrictions of the home country,political security risk of the host country,and sanctions from the West.These findings provide insights for future research:under the wave of anti-globalization and'internal circulation as the main body',resource SOEs should consider the potential risk of investment,especially keeping the middle and downstream industrial chain in China as much as possible. 展开更多
关键词 global production networks global value chain Productive investment Resource SOEs J Group ‘Partly'globalized
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Record-breaking High-temperature Outlook for 2023: An Assessment Based on the China Global Merged Temperature(CMST) Dataset 被引量:3
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作者 Zichen LI Qingxiang LI Tianyi CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期369-376,共8页
According to the latest version(version 2.0) of the China global Merged Surface Temperature(CMST2.0) dataset, the global mean surface temperature(GMST) in the first half of 2023 reached its third warmest value since t... According to the latest version(version 2.0) of the China global Merged Surface Temperature(CMST2.0) dataset, the global mean surface temperature(GMST) in the first half of 2023 reached its third warmest value since the period of instrumental observation began, being only slightly lower than the values recorded in 2016 and 2020, and historically record-breaking GMST emerged from May to July 2023. Further analysis also indicates that if the surface temperature in the last five months of 2023 approaches the average level of the past five years, the annual average surface temperature anomaly in 2023 of approximately 1.26°C will break the previous highest surface temperature, which was recorded in 2016of approximately 1.25°C(both values relative to the global pre-industrialization period, i.e., the average value from 1850 to1900). With El Ni?o triggering a record-breaking hottest July, record-breaking average annual temperatures will most likely become a reality in 2023. 展开更多
关键词 CMST2.0 global mean surface temperature record-breaking temperature El Ni?o
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Global hybrid simulations of soft X-ray emissions in the Earth’s magnetosheath 被引量:2
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作者 Jin Guo TianRan Sun +6 位作者 San Lu QuanMing Lu Yu Lin XueYi Wang Chi Wang RongSheng Wang Kai Huang 《Earth and Planetary Physics》 EI CSCD 2024年第1期47-58,共12页
Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging ... Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a satellite.By performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of Earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic field.In all cases,magnetic reconnection occurs at low latitude magnetopause.The soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the magnetosheath.Local X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray images.Moreover,the magnetopause boundary can be identified using multiple viewing geometries.We also find that solar wind conditions have little effect on the magnetopause identification.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered. 展开更多
关键词 MAGNETOPAUSE X-ray emissivity X-ray imaging SMILE global hybrid-PIC simulation
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GLOBAL SOLUTIONS TO 1D COMPRESSIBLE NAVIER-STOKES/ALLEN-CAHN SYSTEM WITH DENSITY-DEPENDENT VISCOSITY AND FREE-BOUNDARY 被引量:1
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作者 丁时进 李颖花 王喻 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期195-214,共20页
This paper is concerned with the Navier-Stokes/Allen-Cahn system,which is used to model the dynamics of immiscible two-phase flows.We consider a 1D free boundary problem and assume that the viscosity coefficient depen... This paper is concerned with the Navier-Stokes/Allen-Cahn system,which is used to model the dynamics of immiscible two-phase flows.We consider a 1D free boundary problem and assume that the viscosity coefficient depends on the density in the form ofη(ρ)=ρ^(α).The existence of unique global H^(2m)-solutions(m∈N)to the free boundary problem is proven for when 0<α<1/4.Furthermore,we obtain the global C^(∞)-solutions if the initial data is smooth. 展开更多
关键词 Navier-Stokes/Allen-Cahn system density-dependent viscosity free boundary global solutions
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Global Change in Agricultural Flash Drought over the 21st Century 被引量:1
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作者 Emily BLACK 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期209-220,I0002-I0019,共30页
Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop... Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop cultivation. Increases in the frequency of these rare events in a future warmer climate would have significant societal impact. This study uses an ensemble of 10 Coupled Model Intercomparison Project(CMIP) models to investigate the projected change in agricultural flash drought during the 21st century. Comparison across geographical regions and climatic zones indicates that individual events are preceded by anomalously low relative humidity and precipitation, with long-term trends governed by changes in temperature, relative humidity, and soil moisture. As a result of these processes, the frequency of both upperlevel and root-zone flash drought is projected to more than double in the mid-and high latitudes over the 21st century, with hot spots developing in the temperate regions of Europe, and humid regions of South America, Europe, and southern Africa. 展开更多
关键词 flash drought climate change soil moisture agricultural drought CMIP
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Emerging global interest:Unraveling the link between diabetes mellitus and depression 被引量:1
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作者 Samah W Al-Jabi 《World Journal of Psychiatry》 SCIE 2024年第7期1127-1139,共13页
BACKGROUND Studies have shown a strong bidirectional association between diabetes and depression,with diabetes increasing the risk of developing depression and vice versa.Depression among patients with diabetes is ass... BACKGROUND Studies have shown a strong bidirectional association between diabetes and depression,with diabetes increasing the risk of developing depression and vice versa.Depression among patients with diabetes is associated with poor glycemic control,complications,and poor self-care.AIM To explore the present state of research globally concerning diabetes and depression,to aid understanding the current research landscape and identify potential future areas of research.METHODS A bibliometric approach was used,utilizing the Scopus database to gather pertinent research articles released from 2004 to 2023.Analyses encompassed publication patterns,significant contributors,research focal points,prevalent themes,and the most influential articles,aimed at discerning emerging research subjects.RESULTS A total of 3229 publications that met the search criteria were identified.A significant increase in the number of publications related to diabetes and depression has been observed in the past two decades.The most productive nation was the USA(n=1015;31.43%),followed by China(n=325;10.07%),the UK(n=236;7.31%),and Germany(n=218;6.75%).Three principal themes in research on depression and diabetes were delineated by the analysis.First,the exploration of the elevated prevalence and etiology of this comorbidity;second,the focus on interventions,particularly randomized controlled trials,aimed at enhancing diabetes management among individuals with depression;and finally,the investigation of the involved risk factors and biological mechanisms under-lying this bidirectional relationship.CONCLUSION There has been a recent surge of interest in the relationship between diabetes and depression.This could aid researchers to identify areas lacking in the literature and shape future research. 展开更多
关键词 Diabetes mellitus DEPRESSION BIBLIOMETRIC Visualization global
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Research on a Monte Carlo global variance reduction method based on an automatic importance sampling method 被引量:1
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作者 Yi-Sheng Hao Zhen Wu +3 位作者 Shen-Shen Gao Rui Qiu Hui Zhang Jun-Li Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期200-215,共16页
Global variance reduction is a bottleneck in Monte Carlo shielding calculations.The global variance reduction problem requires that the statistical error of the entire space is uniform.This study proposed a grid-AIS m... Global variance reduction is a bottleneck in Monte Carlo shielding calculations.The global variance reduction problem requires that the statistical error of the entire space is uniform.This study proposed a grid-AIS method for the global variance reduction problem based on the AIS method,which was implemented in the Monte Carlo program MCShield.The proposed method was validated using the VENUS-Ⅲ international benchmark problem and a self-shielding calculation example.The results from the VENUS-Ⅲ benchmark problem showed that the grid-AIS method achieved a significant reduction in the variance of the statistical errors of the MESH grids,decreasing from 1.08×10^(-2) to 3.84×10^(-3),representing a 64.00% reduction.This demonstrates that the grid-AIS method is effective in addressing global issues.The results of the selfshielding calculation demonstrate that the grid-AIS method produced accurate computational results.Moreover,the grid-AIS method exhibited a computational efficiency approximately one order of magnitude higher than that of the AIS method and approximately two orders of magnitude higher than that of the conventional Monte Carlo method. 展开更多
关键词 Monte Carlo global variance reduction Reactor shielding Automatic importance sampling
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Projected changes in extreme snowfall events over the Tibetan Plateau based on a set of RCM simulations 被引量:1
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作者 Yuanhai Fu Xuejie Gao 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期3-9,共7页
Extreme snowfall events over the Tibetan Plateau(TP)cause considerable damage to local society and natural ecosystems.In this study,the authors investigate the projected changes in such events over the TP and its surr... Extreme snowfall events over the Tibetan Plateau(TP)cause considerable damage to local society and natural ecosystems.In this study,the authors investigate the projected changes in such events over the TP and its surrounding areas based on an ensemble of a set of 21st century climate change projections using a regional climate model,RegCM4.The model is driven by five CMIP5 global climate models at a grid spacing of 25 km,under the RCP4.5 and RCP8.5 pathways.Four modified ETCCDI extreme indices-namely,SNOWTOT,S1mm,S10mm,and Sx5day-are employed to characterize the extreme snowfall events.RegCM4 generally reproduces the spatial distribution of the indices over the region,although with a tendency of overestimation.For the projected changes,a general decrease in SNOWTOT is found over most of the TP,with greater magnitude and better cross-simulation agreement over the eastern part.All the simulations project an overall decrease in S1mm,ranging from a 25%decrease in the west and to a 50%decrease in the east of the TP.Both S10mm and Sx5day are projected to decrease over the eastern part and increase over the central and western parts of the TP.Notably,S10mm shows a marked increase(more than double)with high cross-simulation agreement over the central TP.Significant increases in all four indices are found over the Tarim and Qaidam basins,and northwestern China north of the TP.The projected changes show topographic dependence over the TP in the latitudinal direction,and tend to decrease/increase in low-/high-altitude areas. 展开更多
关键词 Extreme snowfall Regional climate model Tibetan plateau Climate change
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Background removal from global auroral images:Data-driven dayglow modeling 被引量:1
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作者 A.Ohma M.Madelaire +4 位作者 K.M.Laundal J.P.Reistad S.M.Hatch S.Gasparini S.J.Walker 《Earth and Planetary Physics》 EI CSCD 2024年第1期247-257,共11页
Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth environment.However,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but... Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth environment.However,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but also to dayglow emissions produced by photoelectrons induced by sunlight.Nightglow emissions and scattered sunlight can contribute to the background signal.To fully utilize such images in space science,background contamination must be removed to isolate the auroral signal.Here we outline a data-driven approach to modeling the background intensity in multiple images by formulating linear inverse problems based on B-splines and spherical harmonics.The approach is robust,flexible,and iteratively deselects outliers,such as auroral emissions.The final model is smooth across the terminator and accounts for slow temporal variations and large-scale asymmetries in the dayglow.We demonstrate the model by using the three far ultraviolet cameras on the Imager for Magnetopause-to-Aurora Global Exploration(IMAGE)mission.The method can be applied to historical missions and is relevant for upcoming missions,such as the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission. 展开更多
关键词 AURORA dayglow modeling global auroral images far ultraviolet images dayglow removal
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Creating a New Era for Global Civilization Development by Deepening Exchanges and Mutual Learning
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作者 Li Yuan 《Contemporary World》 2023年第2期18-21,共4页
On March 15, 2023, General Secretary Xi Jinping proposed for the first time the Global Civilization Initiative(GCI) at the CPC in Dialogue with World Political Parties High-level Meeting. The GCI, like the Global Deve... On March 15, 2023, General Secretary Xi Jinping proposed for the first time the Global Civilization Initiative(GCI) at the CPC in Dialogue with World Political Parties High-level Meeting. The GCI, like the Global Development Initiative and the Global Security Initiative, is another important public good provided by China in the new era to address common global challenges and build a shared future for humanity. 展开更多
关键词 global CIVILIZATION HUMANITY
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The Climate Response to Global Forest Area Changes under Different Warming Scenarios in China
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作者 Ying HUANG Anning HUANG Jie TAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第6期1073-1088,共16页
Human activities have notably affected the Earth’s climate through greenhouse gases(GHG), aerosol, and land use/land cover change(LULCC). To investigate the impact of forest changes on regional climate under differen... Human activities have notably affected the Earth’s climate through greenhouse gases(GHG), aerosol, and land use/land cover change(LULCC). To investigate the impact of forest changes on regional climate under different shared socioeconomic pathways(SSPs), changes in surface air temperature and precipitation over China under low and medium/high radiative forcing scenarios from 2021 to 2099 are analyzed using multimodel climate simulations from the Coupled Model Intercomparison Project Phase 6(CMIP6). Results show that the climate responses to forest changes are more significant under the low radiative forcing scenario. Deforestation would increase the mean, interannual variability, and the trend of surface air temperature under the low radiative forcing scenario, but it would decrease those indices under the medium/high radiative forcing scenario. The changes in temperature show significant spatial heterogeneity. For precipitation, under the low radiative forcing scenario, deforestation would lead to a significant increase in northern China and a significant decrease in southern China, and the effects are persistent in the near term(2021–40), middle term(2041–70), and long term(2071–99). In contrast, under the medium/high radiative forcing scenario, precipitation increases in the near term and long term over most parts of China, but it decreases in the middle term, especially in southern, northern,and northeast China. The magnitude of precipitation response to deforestation remains comparatively small. 展开更多
关键词 land use/land cover change DEFORESTATION radiative forcing scenario regional climate
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Predicting changes in the suitable habitats of six halophytic plant species in the arid areas of Northwest China
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作者 YANG Ao TU Wenqin +9 位作者 YIN Benfeng ZHANG Shujun ZHANG Xinyu ZHANG Qing HUANG Yunjie HAN Zhili YANG Ziyue ZHOU Xiaobing ZHUANG Weiwei ZHANG Yuanming 《Journal of Arid Land》 SCIE CSCD 2024年第10期1380-1408,共29页
In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of... In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of Northwest China.Halophytes are ideal for restoring soil salinization because of their adaptability to salt stress.In this study,we collected the current and future bioclimatic data released by the WorldClim database,along with soil data from the Harmonized World Soil Database(v1.2)and A Big Earth Data Platform for Three Poles.Using the maximum entropy(MaxEnt)model,the potential suitable habitats of six halophytic plant species(Halostachys caspica(Bieb.)C.A.Mey.,Halogeton glomeratus(Bieb.)C.A.Mey.,Kalidium foliatum(Pall.)Moq.,Halocnemum strobilaceum(Pall.)Bieb.,Salicornia europaea L.,and Suaeda salsa(L.)Pall.)were assessed under the current climate conditions(average for 1970-2000)and future(2050s,2070s,and 2090s)climate scenarios(SSP245 and SSP585,where SSP is the Shared Socio-economic Pathway).The results revealed that all six halophytic plant species exhibited the area under the receiver operating characteristic curve values higher than 0.80 based on the MaxEnt model,indicating the excellent performance of the MaxEnt model.The suitability of the six halophytic plant species significantly varied across regions in the arid areas of Northwest China.Under different future climate change scenarios,the suitable habitat areas for the six halophytic plant species are expected to increase or decrease to varying degrees.As global warming progresses,the suitable habitat areas of K.foliatum,S.salsa,and H.strobilaceum exhibited an increasing trend.In contrast,the suitable habitat areas of H.glomeratus,S.europaea,and H.caspica showed an opposite trend.Furthermore,considering the ongoing global warming trend,the centroids of the suitable habitat areas for various halophytic plant species would migrate to different degrees,and four halophytic plant species,namely,S.salsa,H.strobilaceum,H.glomeratus,and H.capsica,would migrate to higher latitudes.Temperature,precipitation,and soil factors affected the possible distribution ranges of these six halophytic plant species.Among them,precipitation seasonality(coefficient of variation),precipitation of the warmest quarter,mean temperature of the warmest quarter,and exchangeable Na+significantly affected the distribution of halophytic plant species.Our findings are critical to comprehending and predicting the impact of climate change on ecosystems.The findings of this study hold significant theoretical and practical implications for the management of soil salinization and for the utilization,protection,and management of halophytes in the arid areas of Northwest China. 展开更多
关键词 HALOPHYTES climate change global warming maximum entropy(MaxEnt)model soil salinization suitable habitats Northwest China
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Analysis of piezoelectric semiconductor fibers under gradient temperature changes 被引量:1
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作者 Shuangpeng LI Ruoran CHENG +1 位作者 Nannan MA Chunli ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第2期311-320,共10页
Piezoelectric semiconductors(PSs)possess both semiconducting properties and piezoelectric coupling effects,making them optimal building blocks for semiconductor devices.PS fiber-like structures have wide applications ... Piezoelectric semiconductors(PSs)possess both semiconducting properties and piezoelectric coupling effects,making them optimal building blocks for semiconductor devices.PS fiber-like structures have wide applications in multi-functional semiconductor devices.In this paper,a one-dimensional(1D)theoretical model is established to describe the piezotronic responses of a PS fiber under gradient temperature changes.The theoretical model aims to explain the mechanism behind the resistance change caused by such gradient temperature changes.Numerical results demonstrate that a gradient temperature change significantly affects the physical fields within the PS fiber,and can induce changes in its surface resistance.It provides important theoretical guidance on the development of piezotronic devices that are sensitive to temperature effects. 展开更多
关键词 piezoelectric semiconductor(PS)fiber one-dimensional(1D)model piezotronic effect gradient temperature change
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