THERMAL INFLUENCES OF LAND-SEA CONTRAST AND TOPOGRAPHY ON SUMMER MONSOON IN 1998

In this work, the SCSMEX data are used to diagnose and compare the local land-sea thermal conditions, with the focus of discussion on possible influences of thermal forcing of the western Pacific and the Tibetan Plateau on the onset and development of summer monsoon in 1998. Results show a close relationship between the distribution of the heat sources and the land-sea contrast. Due to the blocking effect of terrain, main maximum zones of the heat sources in areas with more evident north-south land-sea contrast are more obviously southward located than those exclusively with oceans. The surface heating is characterized with apparent seasonal variation and difference between land and sea. The relationship between the western Pacific and the onset of summer monsoon is reflected in the variations of the sea surface temperature (SST) and the latent heat. The influence mechanism of the Tibetan Plateau during the summer monsoon is different: it is dominated by sensible heating during the South China Sea monsoon and by condensed latent heating during the Indian monsoon.

NUMERICAL SIMULATION EXPERIMENTS OF THE IMPACTS OF LOCAL LAND-SEA THERMODYNAMIC CONTRASTS ON THE SCS SUMMER MONSOON ONSET

The important effects of local land-sea thermodynamic contrast between the South China Sea (SCS) and Indochina Peninsula on SCS summer monsoon onset are preliminarily studied by using two sets of SSTA tests and two ideal tests in s-p regional climate model. The result shows that warm SST in the SCS in winter and spring is favorable for the formation of monsoon circulation throughout all levels of the atmosphere over the sea, which hastens the onset of SCS summer monsoon. The effects of cold SST are generally the opposite. The local land-sea contrast in the SCS is one of the possible reasons for SCS summer monsoon onset. Superposed upon large-scale land-sea thermodynamic differences, it facilitates the formation of out-breaking onset characteristics of SCS summer monsoon in the SCS area.

Effects of Land-Sea Distribution, Topography and Diurnal Change on Summer Monsoon Modeling

The effects of the land-sea distribution, the topography and the diurnal change of the solar radiation on the summer monsoon modelings are studied by use of a coupled modeling system with a 5-layer primitive equation model of the atmosphere and a 2-layer soil or ocean thermodynamic model which are all solved in a zonal model domain between 60°S and 60°N. The results of numerical simulations show that the quasi-stationary patterns of the mean monsoon circulations are mainly affected by the land-sea distribution and the topography, the effect of the diurnal change is the secondary. However, the inclusion of the diurnal change into the model system may improve the intensity of the simulated monsoon circulation, it can influence the distributive pattern of precipitation to a larger extent,without the diurnal change precipitation in the interior of land would decrease and in the coastal regions it would increase.

Numerical Modelings of the Climatic Effects of the Land-Sea Distribution and Topography

The effects of the land-sea contrast and the topography on the climatic properties are simulated rn this paper by use of a p- a incorporated coordinate system mode! in a zonal domain.In this paper we firstly discuss the statistical features of the model and find that the capability of the model is stable,with the same land-sea distribution and topography seven monthly mean climate states are close to one another,their variance is even less than the initial one.Secondly,we focally discuss the effects of the land-sea contrast and the topography on the modeled climate fields.It is pointed out that the land-sea contrast and the topography influence the atmosphere mainly through the heating ef-fect and the former has larger influences on the simulated large scale climate fields than the latter.

Land-sea breeze circulation structure on the west coast of the Yellow Sea,China

Land-sea breeze(LSB)is an atmospheric mesoscale circulation that occurs in the vicinity of the coast and is caused by uneven heating resulting from the difference in specific heat capacity between the sea and land surfaces.The circulation structure of LSB was quantitatively investigated with a Doppler wind lidar Windcube100s on the west coast of the Yellow Sea for the first time.The time of observation was 31 August to 28 September 2018.It was found that the height of LSB development was 700 m to 1300 m.The duration of conversion of LSB was between 6 h and 8 h.The biggest average horizontal sea-breeze wind speed at 425 m was 5.6 m s^(-1),and at 375 m it was 4.5 m s^(-1).During the conversion process from sea breeze to land breeze,the maximum wind shear exponent was 2.84 at 1300 m altitude.During the conversion process from land breeze to sea breeze,the maximum wind shear exponent was 1.28 at 700 m altitude.The differences in wind shear exponents between sea-breeze and landbreeze systems were between 0.2 and 3.6 at the same altitude.The maximum value of the wind shear exponent can reflect the height of LSB development.

NUMERICAL EXPERIMENT ON THE EFFECT OF URBANIZATION UPON SUMMER LAND-SEA BREEZES IN THE COASTLAND OF GUANGXI

The 2003-006 observations were utilized to analyze the surface characteristics of summer land-sea breezes along the coastland of Guangxi and the Weather Research and Forecast model was applied to simulate the breeze structure on August 1-2, 2006. Results show that 1） the intensity and distributions of the breezes reproduced from improved urban underlying surface were close to observations. In the daytime the coastwise urban band was a convergent belt of sea breeze, corresponding to the centers of torrential rains; in the nighttime hours the surface of the Gulf of Tonkin （the Vietnamese name） or the Northern Bay （the Chinese name） acted as a convergent zone of land breezes, likely to produce convective cloud cluster; 2） the experiment on urbanization showed the heat island effect enhancing （weakening） the sea （land） breeze development. Furthermore, the heat island effect mitigated the atmospheric cooling via radiation over the cities in the night, weakening sinking motion correspondingly, thereby suppressing the dominant factor responsible for the steady development of temperature inversion. As a result, the inversion vigor was reduced greatly, but nevertheless no strong effect of the decreased subsidence was found upon the inversion height.

向海图强:奋力谱写中国式现代化广西篇章的重要使命与历史责任

党的十八大以来,习近平总书记分别于2017年、2021年和2023年三次视察广西。2023年12月,习近平总书记视察广西时强调,广西要“解放思想、创新求变,向海图强、开放发展”。广西背靠大西南、毗邻粤港澳、面向东南亚,具有沿江、沿海、沿边与东盟“一湾相挽十一国,良性互动东中西”的独特区位优势。向海之路为奋力谱写中国式现代化广西篇章指明方向,向海发展是广西破茧成蝶的根本出路,向海经济是广西高质量发展的重要引擎,向海图强已成为广西新时代新征程的新起点。向海图强既是广西的机遇和优势,也是广西的责任和使命。伴随着系列相关政策文件、战略规划和行动计划的相继颁布实施,广西向海经济发展新格局初步形成。平陆运河建成通航后,将形成广西及西南地区通往东盟的运距最短、最经济、最便捷的运输通道。陆江湾海的联动将撬动区域经济版图,推动形成国内国际双循环战略链接的枢纽。2023年12月习近平主席应邀访问越南具有标志性意义,确立了构建具有战略意义的中越命运共同体,开启了中越两党两国关系发展的新阶段,谱写了新时代中越关系的新篇章,将更有利于广西的向海图强、开放发展。

破解海岸带环境司法困境:基于陆海统筹原则

我国海岸带环境案件存在管辖权冲突、法律适用有争议、原告资格不明确、诉讼性质认定有争鸣、诉讼程序衔接未确定、司法执行机制不完善等环环相扣的问题,造成海岸带环境司法困境。究其根源,主要在于陆海“二分法”的分类思维影响较大,其与陆海统筹合为表里的内涵尚未得到全面、深入的理解。为破解海岸带环境司法困境,既要重视海岸带环境案件的特殊性,将其确立为类型化案件并由海事法院专门管辖,又要贯彻陆海统筹原则,实现司法规则内在融贯、法治环节协调一致。

中国极端天气气候研究——“地球系统与全球变化”重点专项项目简介及最新进展

全球变暖背景下,极端天气气候事件频发,并表现出群发性、持续性、复合性等特点,不可预测性增加;持续性强降水、极端低温、复合型极端高温干旱、群发性热浪和台风等极端天气气候事件对我国经济社会和可持续发展影响巨大。然而,上述极端天气气候事件的新特征、关键过程和机理尚不完全清楚,重大极端事件的预报预测水平亟待提升。文章首先简要介绍“地球系统与全球变化”重点专项项目“中国极端天气气候事件的形成机理及其预测和归因”的基本情况。项目拟在分析全球变化背景下对我国造成重大影响的极端天气气候事件新特征的基础上,深入研究多尺度海-陆-气耦合过程影响极端天气气候事件的机理,挖掘极端天气气候事件次季节-季节预测的前兆信号;发展动力与物理统计相结合的极端事件预测新方法,研制针对中国极端事件的新一代高分辨率数值预报与检测归因系统。文章重点总结了自2022年12月项目立项至今取得的最新研究成果和进展。

关于打通铁路网运输能力堵点对策探究

国铁企业落实党中央部署要求并加快推进铁路货运市场化改革,采取有效措施尽快打通铁路网运输能力堵点,有效降低物流成本。通过分析路网总体规模、旅客运输供给能力、货物运输保障能力等铁路网运输能力现状,剖析铁路网运输能力堵点及成因。在此基础上,提出加强铁路网运输能力经验借鉴,探析打通铁路网运输能力堵点对策,即:畅通普速干线通道,加强煤运通道能力保障,强化中欧班列通道能力,完善港口铁路通过能力,增强西部陆海新通道线路能力,完善枢纽点线配套能力,强化铁路货运设施设备卸车能力等方面,在助力降低全社会物流成本中发挥“火车头”的重要作用。

学习贯彻习近平总书记在新时代推动西部大开发座谈会和视察重庆的重要讲话重要指示精神

为了深入学习贯彻习近平总书记在新时代推动西部大开发座谈会和视察重庆的重要讲话重要指示精神,本刊组织专家围绕党的十八大以来习近平总书记对重庆所作重要讲话和系列重要指示批示精神,结合西南政法大学的实际展开笔谈。本笔谈旨在深入学习贯彻习近平总书记视察重庆重要讲话重要指示精神,围绕法治赋能助力高水平共建西部陆海新通道、党纪学习教育应把握的“五个辩证统一”原则、优化治理机制以提升超大城市社会治理水平、有效防范化解超大城市“新兴风险”等议题,提出了一系列切实可行的建议与措施,以期有益于坚持以国家战略需求为导向,积极融入服务大局,以铁的纪律护航党的事业稳健发展,推动超大城市治理体系与治理能力现代化进程,确保党的事业行稳致远。

Influence of Irregular Coastlines on a Tornadic Mesovortex in the Pearl River Delta during Monsoon Season.Part II:Numerical Experiments

As demonstrated in the first part of this study(Part I),wind-shift boundaries routinely form along the west coast of the Pearl River Delta due to the land-sea contrast of a“trumpet”shape coastline in the summer monsoon season.Through multiple numerical simulations,this article(Part II)aims to examine the roles of the trumpet-shaped coastline in the mesovortex genesis during the 1 June 2020 tornadic event.The modeling reproduced two mesovortices that are in close proximity in time and space to the realistic mesovortices.In addition to the modeled mesovortex over the triple point where strong ambient vertical vorticity was located,another mesovortex originated from an enhanced discrete vortex along an airmass boundary via shear instability.On the fine-scale storm morphology,finger-like echoes preceding hook echoes were also reproduced around the triple point.Results from sensitivity experiments suggest that the unique topography plays an essential role in modifying the vorticity budget during the mesovortex formation.While there is a high likelihood of an upcoming storm evolving into a rotating storm over the triple point,the simulation's accuracy is sensitive to the local environmental details and storm dynamics.The strengths of cold pool surges from upstream storms may influence the stretching of low-level vertically oriented vortex and thus the wrap-up of finger-like echoes.These findings suggest that the trumpet-shaped coastline is an important component of mesovortex production during the active monsoon season.It is hoped that this study will increase the situational awareness for forecasters regarding regional non-mesocyclone tornadic environments.

黄河三角洲地面沉降研究进展与未来展望

黄河三角洲是我国成陆时间最短的大型河口三角洲,由于其发育背景特殊、地质环境系统不稳定以及人类活动影响,地面沉降较为显著,引发了诸多环境问题,对自然环境和社会经济发展产生了严重威胁。从监测技术和成因机理角度出发,系统综述了黄河三角洲地区的地面沉降现状:(1)黄河三角洲地面沉降受新生地层自然压实、人为建筑重力压实、河流陆源输入减少、地下水与卤水开采、石油天然气开采以及海洋动力作用相对增强等多重因素影响,需要更详细、更系统地研究,特别是定量分离人为与自然因素在地面沉降的贡献方面,需要与其他学科如地质、岩土、力学、数学等交叉进行综合定量分析;(2)黄河三角洲地面沉降的长时空尺度的持续监测与分析、历史周期分析与未来判断分析需加强,尤其要重视海陆相互作用对地面沉降的长期和短期影响的研究;(3)地面沉降勘查、监测和精度研究及沉降评估和环境影响监测研究,尤其是海岸带退蚀与地面沉降之间的耦合关系等问题仍待深入。在今后研究黄河三角洲地面沉降的过程中,应更加注重理论模型的深入探究和新技术方法的实践,机理研究应扩展至多种模型研究;预测灾害时,应扩展到与地面沉降问题较为紧密的地面开裂、断层以及地裂缝等研究上。此外,还应对地面沉降的社会经济影响和环境影响等方面做出更多探索和实际应用。全面系统深入地了解黄河三角洲地面沉降现象,可为有效地实施三角洲生态保护和资源开发提供理论依据,具有重要的科学意义和社会经济价值。

基于陆海统筹的资源环境承载力评价方法探讨

海洋、海岸带蕴含的资源丰富,与人类生存发展息息相关。近年来,随着海洋经济的迅速增长,自然岸线和滨海湿地面积减少、生物多样性降低、典型生态系统受损、近岸海域灾害频发、渔业资源减少等问题日益显现。如何从战略高度提升海洋经济,开发和保护并举,确保海岸带、海洋资源取用合理是新时代的重要课题。陆地和海洋是生态系统不可分割的组成部分,开展陆海统筹的资源环境承载力评价是衡量区域经济发展与生态环境是否协调可持续发展的有效途径。文章系统地梳理了承载力概念的发展历程,对比了常用的海洋资源环境承载力评价方法,初步构建了陆海统筹的资源环境承载力评价指标体系,并提出使用熵值法来确定指标权重,采用状态空间评价模型或TOPSIS模型进行承载力综合评价,可以体现陆地和海洋相互影响、相互制约的关系,并具有较强的可操作性,评价结果可以反映区域资源环境承载力的空间差异或随时间变化情况,能够为海洋和海岸带保护利用提供有效借鉴。

论中国式现代化陆海空间全域同一化发展

时空演化规律显示,陆地是人类生活的山水家园,海洋是孕育生命的摇篮,人类生存与发展始终是和海洋连在一起的。在现代世界经济发展中,中国既是拥有辽阔地域空间的陆地大国,又是拥有广阔空间的海洋大国,海洋对国家安全和经济发展具有极其重要的战略地位。在历史发展长河中,中华民族从未中断过陆海空间全域同一化的历史文化经济发展进程。党的二十大后,在习近平新时代中国特色社会主义思想指引下,中国置身于伟大历史转折与第五次改革开放浪潮相互交融的、深入实施“双循环”国家大战略的更新历史性发展阶段。中国共产党领导中国人民在中国式现代化发展的新征程中,加快推进陆地国土空间与海洋(蓝色)经济发展,不断创新以“一带一路”倡议为显著标志的、陆海空间全域同一化发展的新形态新模式新方法,始终如一把握好“魂脉”与“根脉”融为一体的新理念,亦使之成为陆海空间全域同一化发展的“魂与根”。

东北陆海新通道物流体系建设问题与路径研究

东北陆海新通道是中蒙俄经济走廊建设的新通道,对深化中国、蒙古国和俄罗斯的共同发展与经贸合作具有重要作用。以交通基础设施互联互通为基本目标,从系统观念视角构建了“枢纽+通道+网络”全方位的东北陆海新通道物流体系。为有效提升通道区域的经贸合作水平,提出了通道育物流、物流促贸易、贸易带产业、产业拉经济的通道物流体系发展模式。基于物流系统的六项流动要素阐释了新通道的发展现状,针对面临的“软硬”联通堵点尚存、建设资金保障不足、合作思想亟待拓展、统筹规划尚不全面等问题,提出了相应对策与实现路径。东北陆海新通道物流体系的建设与完善对东北地区深度融入共建“一带一路”与全面振兴具有极其重要的战略价值。

海-陆交互作用与海岸带碳中和农业驱动

海岸带既是生态脆弱区也是低碳农业发展“前哨”。推动和发展碳中和农业符合时代所需,也符合绿色、可持续发展理念。基于此,本文阐述了在海岸带区域发展碳中和农业的相关问题和重要性。首先,本文阐释了海陆交互作用以及海岸带碳中和农业发展理念;然后,分析了海岸带碳中和农业驱动中的碳中和农业生物、人工光合作用与农业驱动以及该理念的工程化应用问题;最后,深入剖析了如何识别海岸带农业核心碳汇,包括原位监测、同位素标记与统计学分析方法,并在此基础上提出了农业碳汇增强技术,为后续海岸带碳中和农业的构建、发展和实践提供参考,同时对促进脆弱的海岸带生态系统的保护和绿色低碳农业的发展具有重要意义。

国际地缘大变局下的越欧班列规划与中越铁路对接

越南经济发展高度依赖于外贸驱动。随着外贸总量的不断扩大,原有以海路为主的外贸线路不仅日益难以满足对外货运的需求,而且潜藏着安全上的风险,中美战略竞争的加剧和新冠疫情的爆发则进一步暴露了越南海运能力不足的发展瓶颈。在此背景下,越南提出了越欧班列规划,试图通过中越铁路对接或者通过中南半岛东西交通走廊经印度和中东西亚打通连接越南—欧洲的外贸新通道,改变过度依赖海路运输的不利局面,实现外贸路线的多元化和均衡化,消除潜在的安全风险。随着俄乌冲突、中东乱局和红海危机等一系列地缘变局的发生,经中南半岛和印度洋的方案最终搁浅,而通过中越铁路对接,在中欧班列的基础上建设越欧班列成为唯一可行的方案。中越两国铁路对接意味着中南半岛南北铁路交通线与中国西部陆海新通道实现完全联网,并进一步将中国、中南半岛、中亚、中东、南亚和欧洲连为一体,不仅将为中越关系发展注入新动力,更将为中国周边和中南半岛地区带来更大的稳定性,助力高质量“一带一路”建设,推动国际秩序向着更加公平合理的方向发展。

南亚抗震不利地段海陆交互复杂互层地基加固性能研究

针对孟加拉国某港口工程海陆交互相复杂互层地基加固中遇到的地层特性复杂、加固效果难以预测以及软黏土和粉细砂互层土场地地震液化的问题,结合场地地质条件、使用功能、工程特点等,对插板预压联合降水强夯在该场地条件下的加固效果展开研究。依托项目试验区块,通过对加固前后土体物理力学指标的对比分析和沉降-时程曲线、孔隙水压力-时程消散曲线等的研究,得到插板预压联合降水强夯加固的过程特性以及对原状土和吹填土的加固效果。研究表明,插板预压联合降水强夯法对于复杂互层土上吹填砂场地具有较好的适应性,加固效果可满足设计承载力和工后沉降控制要求,该法对于减轻砂土层的液化具有一定的作用。研究成果对于南亚地区复杂互层土吹填场地设计具有指导意义。

陆海统筹下海岸带生态环境修复法律制度研究

近些年,中国各沿海地区在海岸带生态环境保护和修复方面开展了一些实践,陆续出台了相关的政策文件,但中国海岸带生态环境修复的结果仍不理想。文章主要以陆海统筹为研究背景,全面分析海岸带生态环境修复存在的问题与发展趋势,梳理中国现行政策与制度存在的修复立法尚不健全、环境主体范围较窄、修复标准不明确等问题。从而根据中国海岸带生态环境发展现状,提出有利于海岸带环境修复的意见和建议。