西太平洋副热带高压对热带 海温异常响应的研究   总被引：34，自引：5，他引：29  

应明  孙淑清 《大气科学》2000,24(2):193-206

利用多年的观测资料,研究了西太平洋副热带高压对热带海温异常的响应及其相互作用过程。着重研究冬、夏季西太平洋副高对同期及前期不同海域（特别是赤道东、西太平洋以及印度洋海域）海温异常的响应;用SVD方法分析了夏季副热带高压与前冬、前春及同期各月全球海温的最佳耦合模态。在对比研究西太平洋副热带高压异常时其垂直环流变化的基础上,进而研究海气相互作用对副热带高压影响的物理过程。  相似文献   

北黄海冷水团环流结构探讨──潮混合锋对环流结构的影响   总被引：10，自引：4，他引：10  

赵保仁 《海洋与湖沼》1996,27(4):429-435

简述北黄海冷水团环流结构研究现状，指出已有研究成果中的主要问题，然后用一个诊断模型给出了冷水团环流结构，得到冷水团环向主要存在于海洋上层接近冷水团边界处，径向运动也主要存在于断面两端，上层为离岸流，下层为向岸流；冷水团中心的上升流极为微弱，且仅存在于海洋上层，温跃层下的冷水团中心区域的流动极为微弱，几乎为“死水”一般，上述环流结构对冷水团中心部分的温、盐度长期保持不变及跃层底部溶解氧最大值的形成和  相似文献   

珠江伶仃河口湾及邻近内陆架的纵向环流与物质输运分析   总被引：1，自引：0，他引：1  

陈子燊 《热带海洋学报》1993,(4)

根据实测资料分析了珠江伶仃河口湾与邻近内陆架在不同径流影响下的水体混合空间状态和季节变化特征。主要由河口湾表、中层冲淡水和内陆架底层上溯的高盐补偿流构成了河口湾和内陆架之间的净环流,在高径流量和西南大风的情况下,环流下移向内陆架扩展增强。计算表明,7月纵断面上的净环流输运是盐分纵向净通量的控制因素,输运方向指向上游,而其余季节则以向海的净平流输运为主。悬沙净通量主要受净平流及潮抽吸输运控制,潮抽吸输运强度与大小潮有较密切关系。  相似文献   

Flow Adjustments Across Sea-Surface Temperature Changes     

L. Smahrt  Dean Vickers  Erin Moore 《Boundary-Layer Meteorology》2004,111(3):553-564

The adjustment of airflow across sea-surface temperature changes is examinedusing aircraft eddy-correlation data. Major features of the observed flow adjustmentare not included in the theory of internal boundary layers. However, the data samplesize and coverage are not sufficient to accurately quantify the additional influences.With flow from warm water over cooler water, substantial turbulence intermittentlydevelops above the newly formed surface inversion layer. The corresponding,spatially-averaged, downward momentum flux is stronger than that close to the surface.With stably stratified flow over modest increases of sea-surface temperature, areduction of stratification can trigger episodic shear generation of turbulence. Inthese cases, the primary role of increasing surface temperature in the downwinddirection is to induce shear generation of turbulence. With larger increases ofsurface temperature, upward heat flux generates turbulence, warms the air and generates a significant horizontal gradient of hydrostatic pressure. This contributionto the pressure field appears to strongly modify the flow. Major inadequacies inexisting data and future needs are noted.  相似文献   

南大洋大气氧化亚氮分布特征          下载免费PDF全文

詹力扬  陈立奇 《极地研究》2007,19(1):49-60

在执行中国第21次南极科学考察任务期间,于2004年11月15日至2005年2月2日在南大洋(澳大利亚以南以及中山站和长城站之间环绕南极海域)航线上采集大气氧化亚氮样品,并带回陆地实验室分析。结果显示,大气氧化亚氮浓度由澳大利亚至中山站航段的(309.6±1.6)nL/L上升至环绕南极冰边缘海区航段的(320.0±1.2)nL/L。这种南大洋大气中氧化亚氮浓度随纬度升高而升高的特征,可能与洋流作用,季节性海冰融化、生物作用以及近岸等的影响因素有关。  相似文献   

Phylogeography of the mud crab (Scylla serrata) in the Indo‐West Pacific reappraised from mitochondrial molecular and oceanographic clues: transoceanic dispersal and coastal sequential colonization     

Lijun He  Zhenguo Qiao 《Marine Ecology》2011,32(1):52-64

The widespread mud crab, Scylla serrata, of the Indo‐West Pacific is an excellent model species to demonstrate how the colonization history of a species can be influenced by complex oceanographic conditions. Through the combination of ecological data (fossil records and paleo‐oceanographic conditions) and molecular data (coalescent simulations, network analysis, and nucleotide diversity tests), the phylogeographic history of S. serrata was re‐analyzed. Based on the analysis of mtDNA cytochrome oxidase I sequences, two major clades were identified for S. serrata, including a widespread clade (Clade I) with three disjunct geographic clusters (IA, IB and IC) and an endemic Northwest Australian clade (Clade II). Moreover, a significant phylogeographic structure corresponding to four subpopulations was revealed: Northwest Australia, West Indian Ocean, Red Sea‐South China Sea and West Pacific. A colonization history of a Northwest Australia origin for S. serrata followed by westward transmarine dispersal across the Indian Ocean for Clade I and sequential colonization from the West Indian Ocean to Red Sea‐South China Sea and West Pacific was corroborated. The Pleistocene fluctuations of paleo‐oceanographic conditions including surface circulations and physical topography in the Indo‐West Pacific might be responsible for the wide distribution, colonization history and genetic divergence of this species.  相似文献   

2010年以来华西秋季降水年代际增多原因初探          下载免费PDF全文

徐曼琳  周波涛  程志刚 《大气科学学报》2020,43(3):568-576

基于1961-2016年降水资料和NCEP/NCAR再分析数据,分析了华西秋季降水的年代际变化特征。结果表明,华西秋季降水在20世纪80年代中期前偏多,之后减少,21世纪10年代又开始增多,而且该时段的降水量多于20世纪80年代中期前。进一步从大气环流角度,初步探讨了这种年代际变化的成因。研究发现,与华西降水偏少阶段相比,在两个降水偏多期,巴尔喀什湖低压槽加深、亚洲区域海平面气压（Sea Level Pressure,SLP）负异常,利于高纬冷空气南下入侵华西区域;东亚低空盛行异常偏南风,利于低纬水汽向华西区域输送;东亚西风急流位置偏北,提供华西降水发生的动力抬升条件,共同造成华西秋季降水增加。相比于20世纪80年代前,21世纪10年代后欧洲高压脊和巴尔喀什湖槽更强,更利于高纬冷空气进入华西区域。同时,有来自南半球印度洋的水汽向华西区域输送。更强的冷空气活动和更多的水汽输送导致后一阶段降水更多。  相似文献   

A comparative study of the atmospheric circulations associated with rainy-season floods between the Yangtze and Huaihe River Basins   总被引：1，自引：0，他引：1  

PING Fan  TANG XiBa  GAO ShouTing  LUO ZheXian 《中国科学:地球科学(英文版)》2014,57(7):1464-1479

Here we present the results from the composite analyses of the atmospheric circulations and physical quantity fields associated with rainy-season for the selected floods cases over the Yangtze and Huaihe River basins for the 21 years(1990–2010),using the daily rain gauge measurements taken in the 756 stations throughout China and the NCEP/reanalysis data for the rainyseasons(June–July)from 1990 to 2010.The major differences in the atmospheric circulations and physical quantity fields between the Yangtze and Huaihe River basins are as follows:for flooding years of the Yangtze River Basin,the South Asia high center is located further east than normal,the blocking high over the Urals and the Sea of Okhotsk maintains,and the Meiyu front is situated near 30°N whereas for flooding years of the Huaihe River Basin,the South Asia high center is further west than normal,the atmospheric circulations over the mid and high latitudes in the Northern Hemisphere are of meridional distribution,and the Meiyu front is situated near 33°N.In addition,there are distinct differences in water vapor sources and associated transports between the Yangtze and Huaihe River basins.The water vapor is transported by southwesterly flows from the Bay of Bengal and monsoon flows over the South China Sea for flooding years of the Yangtze River Basin whereas by southeast monsoons from the eastern and southern seas off China and monsoon flows over the South China Sea for flooding years of the Huaihe River Basin.  相似文献   

夏季东亚高空西风急流气候特征分析   总被引：2，自引：0，他引：2  

卫玮  黄卓禹 《沙漠与绿洲气象(新疆气象)》2012,6(4):21-26

利用NCEP/NCAR全球再分析风场资料定义了西风急流强度指数和位置指数,然后利用EOF方法对西风急流进行了进一步的分析,分析了高空西风急流的空间分布特征,从强度和位置两方面分析了西风急流与东亚环流及其与海温的关系。分析表明： EOF第一模态反映了东亚高空急流的位置指数,第二模态反映了高空急流的强度指数。东亚高空急流与对流层大气环流包括南亚高压,西太平洋副热带高压,东亚夏季风存在着密切关系,其气候变化与热带副热带东太平洋、印度洋海温密切相关。  相似文献   

南海海洋环流季节变化的数值模拟研究          下载免费PDF全文

许婷  曹永港 《海岸工程》2017,36(1)

基于POM(Princeton Ocean Model)海洋模式,对南海不同深度环流的季节性变化进行了数值模拟研究。模拟结果表明:南海表层和上层环流受季风影响,在夏季西南季风驱动下,南海表层环流在南部呈现强反气旋式结构,在南海北部则是一个弱的气旋环流;在冬季东北季风驱动下,南海表层环流结构呈气旋式,并且明显加强了沿越南沿岸向南流动的西边界流;春季和秋季为南海季风的转换期,其对应的环流特征也处于冬季环流与夏季环流的过渡流型,流速与冬季和夏季相比较弱。南海200m层环流的季节变化与表层相似。在500与1 000m层,则出现许多处中尺度漩涡,流场也变得较为紊乱。  相似文献