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Structure of the Potential Vorticity of an Explosive Cyclone over the Eastern Asian Region in Late November 2013

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Journal of Ocean University of China 2022年第2期21卷 253-263页

作者： PANG Huaji FU Gang lu chungu Qingdao Engineering Technology Research Center for Meteorological Disaster Prevention Qingdao Meteorological BureauQingdao 266003China Department of Marine Meteorology Laboratories of Physical OceanographyOcean-Atmosphere Interaction and ClimateOcean University of ChinaQingdao 266100China National Science Foundation ArlingtonVA 22230USA

An explosive extratropical cyclone(EC)over the Eastern Asian region that caused two shipwrecks is analyzed using ERA-Interim reanalysis data from the European Center for Medium-Range Weather *** of the evolution of the EC reveal that the positive potential vorticity(PV)at the upper-tropospheric level displays a hook-shaped structure during the mature period of the *** PV distribution forms a vertically coherent PV structure called a PV *** vertical distribution of the PV can induce and strengthen cyclonic circulation from the lower-to upper-levels of troposphere,which is an important deepening mechanism of explosive *** PV tower occurs approximately ten hours prior to the development of surface occlusion in the *** evolution of surface fronts closely follows the development of the horizontal upper-tropospheric *** tandem development is largely attributed to the ability of the positive upper-tropospheric PV and the PV tower to induce cyclonic circulation *** kinematic wrap-up process of cyclonic circulation also accelerates the formation of warm occlusion.A conceptual model of the distributions of positive PV and potential temperature combining the perspectives of dynamic tropopause folding,PV tower,and atmospheric stability,including westward tilting and baroclinicity,is *** model can illustrate the explosive deepening mechanism of *** regions of convective instability and rainfall determined by this model are consistent with those identified from the actual observation.

关键词： extratropical cyclone rapidly deepening mechanism potential vorticity front evolution coupling of upper-and low-troposphere

A Generalized Frontogenesis Function and Its Application

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Advances in Atmospheric Sciences 2014年第5期31卷 1065-1078页

作者： YANG Shuai GAO Shouting lu chungu Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of Sciences State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences U.S. National Science Foundation Arlington VA 22230 USA

With the definition of generalized potential temperature, a new generalized frontogenesis function, which is expressed as the Lagrangian change rate of the magnitude of the horizontal generalized potential temperature gradient, is derived. Such a frontogenesis function is more appropriate for a real moist atmosphere because it can reflect frontogenesis processes, in which the atmosphere in a frontal zone is typically characterized by neither completely dry nor uniform saturation. Furthermore, by derivation, the expression of generalized frontogenesis function includes both temperature and humidity gradients, which is different from and superior to the traditional frontogenesis function in moist processes, which also uses equivalent potential temperature. Diagnostic studies of real cases are performed and show that the generalized frontogenesis function in non- uniformly saturated moist atmosphere indeed provides a useful tool for frontogenesis, compared to using the traditional frontogenesis function. The new frontogenesis function can be used in situations involving either a strong temperature or moisture gradient and is closely correlated with precipitation.

关键词： frontogenesis diagnostic analysis case study

Scaling the Microphysics Equations and Analyzing the Variability of Hydrometeor Production Rates in a Controlled Parameter Space

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Advances in Atmospheric Sciences 2002年第4期19卷 619-650页

作者： chungu lu Paul Schultz and Gerald L Browning NOAA Forecast Systems Laboratory Boulder USA Cooperative Institute for Research in the Atmosphere Colorado State University Fort Collins USA

A set of microphysics equations is scaled based on the convective length and velocity scales. Comparisons are made among the dynamical transport and various microphysical processes. From the scaling analysis, it becomes apparent which parameterized microphysical processes present off-scaled influences in the integration of the set of microphysics equations. The variabilities of the parameterized microphysical processes are also studied using the approach of a controlled parameter space. Given macroscopic dynamic and thermodynamic conditions in different regions of convective storms, it is possible to analyze and compare vertical profiles of these processes. Bulk diabatic heating profiles for a cumulus convective updraft and downdraft are also derived from this analysis. From the two different angles, the scale analysis and the controlled-parameter space approach can both provide an insight into and an understanding of microphysics parameterizations.

关键词： cloud microphysical parameterization scale analysis controlled parameter space numerical weather prediction

On Spatiotemporal Characteristics of Sea Fog Occurrence over the Northern Atlantic from 1909 to 2008

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Journal of Ocean University of China 2016年第6期15卷 958-966页

作者： LI Pengyuan WANG Guanlan FU Gang lu chungu Laboratory of Physical Oceanography Ocean-Atmosphere Interaction and Climate Department of Marine Meteorology Ocean University of China Qingdao 266100 P. R. China National Meteorological Center Chinese Meteorological Administration Beijing 100081 P. R. China National Science Foundation Arlington VA 22230 ~USA

In this paper, the International Comprehensive Ocean and Atmosphere Data Set(ICOADS) is utilized to investigate the horizontal distribution of sea fog occurrence frequency over the Northern Atlantic as well as the meteorological and oceanic conditions for sea fog formation. Sea fog over the Northern Atlantic mainly occurs over middle and high latitudes. Sea fog occurrence frequency over the western region of the Northern Atlantic is higher than that over the eastern region. The season for sea fog occurrence over the Northern Atlantic is generally from April to August. When sea fogs occur, the prevailing wind direction in the study area is from southerly to southwesterly and the favorable wind speed is around 8 m s-1. It is most favorable for the formation of sea fogs when sea surface temperature(SST) is 5℃ to 15℃. When SST is higher than 25℃, it is difficult for the air to get saturated, and there is almost no report of sea fog. When sea fogs form, the difference between sea surface temperature and air temperature is mainly-1 to 3℃, and the difference of 0℃ to 2℃ is the most favorable conditions for fog formation. There are two types of sea fogs prevailing in this region: advection cooling fog and advection evaporating fog.

关键词： atmospheric visibility sea fog occurrence frequency the Northern Atlantic

青藏高原热力强迫对中国东部降水和水汽输送的调制作用

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气象学报 2015年第1期73卷 20-35页

作者：徐祥德赵天良施晓晖 lu chungu 中国气象科学研究院灾害天气国家重点实验室北京100081 南京信息工程大学中国气象局气溶胶-云-降水重点实验室南京210044 National Science Foundation VA 22230USA

从4个方面综述了有关青藏高原大地形热力"驱动"对中国东部雨带和水汽输送特征及其年代际变化的影响作用的研究进展:(1)中国三阶梯大地形热力过程变化与季风雨带季节演进;(2)青藏高原地-气过程热力"驱动"及其季风水汽输送结构;(3)青藏高... 详细信息

从4个方面综述了有关青藏高原大地形热力"驱动"对中国东部雨带和水汽输送特征及其年代际变化的影响作用的研究进展:(1)中国三阶梯大地形热力过程变化与季风雨带季节演进;(2)青藏高原地-气过程热力"驱动"及其季风水汽输送结构;(3)青藏高原积雪冷源对中国东部水汽输送结构及其雨带分布的影响;(4)青藏高原视热源变化与雨带年代际变化相关特征及其可能调制。其主要研究结论是:(1)中国西部高原特殊三阶梯大地形结构强化了海-陆热力差异,尤其是高原大地形使地-气热力差异季节变化有由青藏高原向东北方向大地形区域延伸变化趋势,且其与季风雨带由东南沿海移向西北朝青藏高原与黄土高原边缘同步演进,两者似乎存在类似季节内演进的一种"动态的吸引"。(2)中国东部雨带时空变化特征和季风强弱变化趋势均与青藏高原热源强弱异常变化相对应。青藏高原热源异常影响低纬度海洋向陆地的水汽传输路径和强度,进而调制中国东部降水时空演变。在青藏高原热源强和弱年,中国降水变率空间分布特征分别为"北涝南旱"和"南涝北旱"。青藏高原视热源强(弱)异常变化"强信号"将对东亚与南亚区域的季风水汽输送结构,以及夏季风降水时空分布的变异具有"前兆性"的指示意义。(3)长江中下游地区作为独特南北两支水汽流的汇合带,该地区夏季青藏高原热源与水汽通量相关矢特征呈类似于青藏高原多雪与少雪年水汽通量偏差场中水汽汇合区显著特征差异,揭示了冬季青藏高原积雪冷源影响中国东部夏季长江流域梅雨水汽输送结构特征。(4)中国降水的年代际变化基本型态为中国东部呈"南涝北旱趋势",西北区域呈现出"西部转湿趋势"。但基于近10年青藏高原春季视热源出现"降后回升"趋势,中国东部"南涝北旱"的降水格局已出现转折趋势。

关键词：青藏高原降水调制作用季风雨带水汽传输视热源

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青藏高原大气水分循环特征

气象学报 2014年第6期72卷 1079-1095页

作者：徐祥德赵天良 lu chungu 施晓晖中国气象科学研究院灾害天气国家重点实验室北京100081 南京信息工程大学中国气象局气溶胶-云-降水重点实验室南京210044 National Science Foundation VA 22230USA

青藏高原对亚洲季风环流的形成有重要作用,同时作为"世界屋脊"拥有丰富的冰川、积雪、河流、湖泊和地下蓄水层。青藏高原特殊大地形动力和热力作用深刻地影响着亚洲与全球大气水分循环,也对全球气候与环境产生深远的影响。基于青藏高原... 详细信息

青藏高原对亚洲季风环流的形成有重要作用,同时作为"世界屋脊"拥有丰富的冰川、积雪、河流、湖泊和地下蓄水层。青藏高原特殊大地形动力和热力作用深刻地影响着亚洲与全球大气水分循环,也对全球气候与环境产生深远的影响。基于青藏高原在亚洲夏季风系统大气水分循环过程的重要地位,从青藏高原对全球大气水分循环重要作用的视角,综述了青藏高原大气水分循环过程中青藏高原局地热力对流、高原的"阶梯式"水汽流爬升"第二类条件不稳定(CISK)"物理模型、青藏高原视热源结构影响及多尺度水汽汇流通道、海洋-青藏高原"水汽源-汇"结构、青藏高原跨半球垂直环流圈水分循环结构、青藏高原大气水分循环综合模型等的相关研究进展,剖析了青藏高原大气水分循环综合模型的研究背景,探讨了青藏高原特殊大地形热力驱动机制及其云水效应,描述出与青藏高原热力驱动的亚洲区域和跨半球垂直环流圈水分循环结构,揭示了青藏高原热力强迫与海洋-大气-陆地水文过程特殊的相互反馈作用。青藏高原发源的亚洲河流水系是为人口众多的亚洲区域供给生活、农业和工业用水的重要水资源之一。因此,认识在全球变暖背景下青藏高原的水分循环及其对水资源变化影响至关重要,仍需深入地探讨青藏高原大气水分循环机制及其全球影响效应。

关键词：青藏高原水分循环亚洲季风水汽输送全球变暖

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抗半乳糖抗体相关疾病及其临床应用进展

医学综述 2017年第1期23卷 25-29页

作者：洪春姑刘璐何琛蔡志明牟丽莎深圳市第二人民医院驯化器官工程技术研究开发中心广东深圳518000

抗半乳糖(Gal)抗体是人体最丰富的天然抗体,与多种免疫疾病密切相关。Gal抗原在甲状腺细胞表面的异常表达导致了Graves病;病原体携带或分泌的Gal抗原,可引发机体出现"类自身免疫性疾病"的炎症反应;抗Gal抗体也是异种器官移植的免疫屏障... 详细信息

抗半乳糖(Gal)抗体是人体最丰富的天然抗体,与多种免疫疾病密切相关。Gal抗原在甲状腺细胞表面的异常表达导致了Graves病;病原体携带或分泌的Gal抗原,可引发机体出现"类自身免疫性疾病"的炎症反应;抗Gal抗体也是异种器官移植的免疫屏障。在抗病毒、细菌和肿瘤疫苗中表达Gal表位,可提高疫苗的免疫原性;注射Gal脂多糖还可将肿瘤细胞转变为自体抗肿瘤疫苗,而Gal纳米颗粒可加速切口愈合和组织修复。

关键词：抗半乳糖抗体 Gal表位增加免疫原性肿瘤疫苗切口愈合

Synthesis of a-Boryl Alcohol from Alcohol/Ketone based on iron catalysis: Building a Boryl-Enabled Mode for Alcoholic C-O Functionalizations

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Synthesis of a-Boryl Alcohol from Alcohol/Ketone based on ir...

过渡金属催化CO_2与C—H键直接羧化反应的研究进展

中国化学会第十六届全国均相催化学术会议

作者：朱庆 Zeyu He lu Wang Yue Hu chungu Xia Chao Liu 兰州化学物理研究所苏州研究院 State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research Institute of LICPLanzhou Institute of Chemical Physics (LICP) Chinese Academy of Sciences

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有机化学 2016年第12期36卷 2813-2821页

作者：朱庆王露夏春谷刘超中国科学院兰州化学物理研究所兰州730000 中国科学院大学北京100049

CO_2是目前最大的碳源之一,将CO_2用于合成有机化合物无疑是清洁能源利用的一种新策略,作为CO_2参与有机合成反应的主要产物,羧酸及其衍生物也有着广泛的应用.在众多CO_2参与的羧化反应方法中,C—H键与CO_2的直接羧化反应是最高效的同... 详细信息

CO_2是目前最大的碳源之一,将CO_2用于合成有机化合物无疑是清洁能源利用的一种新策略,作为CO_2参与有机合成反应的主要产物,羧酸及其衍生物也有着广泛的应用.在众多CO_2参与的羧化反应方法中,C—H键与CO_2的直接羧化反应是最高效的同时也是目前研究十分热门的一类有机化学反应.对近年来CO_2与不同杂化态C—H键的直接羧化反应的研究进行总结,主要讲述过渡金属催化的反应体系.

关键词： C-H羧化 CO2 过渡金属催化