南海海流对冬季风风应力的响应特征

本文用美国普林斯顿大学海洋模式（ＰＯＭ）的南海版本（ＳＣＳ－ＰＯＭ） 模拟了持续冬季风风应力作用下,南海海流的响应特征。结果表明,从静止的海洋 出发,定常冬季风风应力驱动下的南海海流有明显的时间变化,垂直积分后的海流 （全流）约需１２０天左右的时间,方能达到准稳定态,表层、次表层和深层海流的时 间演变也有类似特征。模拟结果还表明,ＳＣＳ－ＰＯＭ有能力模拟出南海边界流、沿 岸流和海流的涡旋状结构。     

南海海流对冬季风应力的响应特征

本文用美国普林斯顿大学新式（ＰＯＭ）的南海版本（ＳＣＳ－ＰＯＭ）模拟了抟续冬季风风应力作用下,南海海流的响应特征。结果表明,从静止的海洋出发,定常冬季风风应力驱动下的南海海流有明显的时间变化,垂直积分后的海流（全流）约需１２０天左右的时间,方能达到准稳定态,表层、次表层和深层海流的时间演变也有类似特征。模拟结果还表明,ＳＣＳ－ＰＯＭ有能力模拟出南海边界流、沿岸流和海流的涡旋状结构。     

南海海平面高度年循环的特征

根据 ＴＯＰＥＸ／ ＰＯＳＥＩＤＯＮ－ＥＲＳ高度计提供的海平面高度异常资料和并行海洋气候模式（ＰＯＣＭ）模拟海平面高度资料，分析了南海海平面高度年循环特征。结果表明：ｌ月，３月和５月海平面高度的异常值分别与７月，９月，１１月的异常值相反。ｌ月（７月），深水海区与吕宋海峡的海平面高度为负（正）异常，在大部分陆架区和南海的西和南部，海平面高度为正（负）异常。在３月（９月），除海平面高度异常的量级已减少，且较小的ＳＳＨ正异常（负异常）出现在南海的中部以外，海平面高度异常的分布型与 １月（７月）类似； ＳＳＨ的年循环的最大振幅出现在吕宋岛的西北海域；风的季节变化是南海ＳＳＨ季节变化的主要原因。     

TOGACD－ROM资料介绍（续）

ＴＯＧＡＣＤ－ＲＯＭ资料介绍（续）国家自然科学基金委员会地球科学部南京气象学院大气资料服务中心资料通讯第２卷第４期（总第７期）１９９５年１０月４ＧＥＯＳＡｒ海面高度资料这些资料由ＮＯＡＡＮａｔｉｏｎａｌＳｅｒｖｉｃｅ提供。原始资料是ＧＥＯＳＡＴ（Ｇｅ...     

西太平洋暖池次表层海温一场与ENSO关系的CGCM模拟结果

全球大气与热带太平洋相耦合的数值模式（ＣＧＣＭ） 很好地模拟了ＥＮＳＯ （ 厄尔尼诺和拉尼娜） 型海表水温（ＳＳＴ） 异常, 进一步分析多年的模式积分结果, 清楚地表明赤道中东太平洋ＳＳＴ 异常与西太平洋暖池次表层（ 深１００ ～２００ ｍ） 的海温异常有密切的关系。在Ｅｌ Ｎｉｎｏ 事件发生之前的半年到一年左右, 西太平洋暖池次表层海温有明显正异常,并向东传播; 而在Ｌａ Ｎｉｎａ 发生之前的半年到一年左右, 暖池次表层海温有明显负异常, 并向东传播。因此, 西太平洋暖池次表层海温异常及其东传对Ｅｌ Ｎｉｎｏ （Ｌａ Ｎｉｎａ） 的发生有极重要作用。     

温度,盐度和风应力对南海海流模拟的影响

用美国普林斯顿大学海洋模式（ＰＯＭ）对南中国海的年平均海流进行了数值模拟,对温盐结构和风应力在海流形成中的作用进行了较详细的讨论。结果表明,仅有温盐水平不均匀分布也可以驱动海水而生成南海海流,但此种海流的结构较乱,最大流速只有３０～４０ｃｍ·ｓ－１。若温盐无水平结构,则在风应力驱动下,南海海流的结构较为有序,且最大流速可增至６０～７０ｃｍ·ｓ－１。在温盐水平分布不均匀并有风应力的作用时,生成的南海海流与仅有风应力作用时的海流场较相似,说明在南海海流的形成中,风应力的作用更为重要。海面自由高度的分析也证明了上述结论。     

两层原始方程海流数值模式和模拟

设计了一个两层原始方程海流数值模式，利用１月和７月多年平均的海平面气压场和由该气压诊断出的海面风场，对此模式的性能进行了检验，结果表明，模拟得出的海洋表层及次表层流与实况较为一致，文中还将模拟结果和ＩＡＰ ＯＧＣＭ以及ＯＳＵ ＯＧＣＭ的相庆结果作了初步比较和分析。     

TEMPERATURE-MEASURING RADIO-ACOUSTIC SOUNDING SYSTEM(RASS)

ＴＥＭＰＥＲＡＴＵＲＥ－ＭＥＡＳＵＲＩＮＧＲＡＤＩＯ－ＡＣＯＵＳＴＩＣＳＯＵＮＤＩＮＧＳＹＳＴＥＭ（ＲＡＳＳ）￥ＬｉＪｉａｎｇｕｏ（李建国），ＷａｎｇＰｉｎｇ（王坪）ａｎｄＭｅｎｇＺｈａｏｌｉｎ（孟昭林）ＴＥＭＰＥＲＡＴＵＲＥ－ＭＥＡＳＵＲＩＮＧＲＡ...     

南海夏季风爆发与海温和大气对流的低频变化

根据云顶黑体温度（ＴＢＢ）相位变化并参考西沙站海面温度（ＳＳＴ）状况确定了南海夏季风爆发时间,分析研究了与夏季风爆发时间和强度有关的ＴＢＢ和ＳＳＴ变化过程,结果表明：南海夏季风爆发平均时间是５月第４候,爆发的时间和强度有显著的年际变化,爆发期间的海气状况与大气的低频振荡密切相关。夏季风爆发早年（５月第２候）,大气对流活动较强,西南风较强,海温下降我年（６月第１候）情况则相反;它爆发的强度还与爆发期     

POM对南海海温年变化的模拟

将Internet上的美国普林斯顿大学海洋模式（POM）改造为能够模拟南海（SCS）海洋要素的模式。在POM中,加入了真实的南海海底地形,使用了误差扣除的压力梯度计算方法,引进了海气界面上热通量计算方案,增加了前置和后置处理程序,使模式能够根据研究目的,模拟和预测海洋要素的时间变化及空间分布。利用改造后的POM模拟了南海海温的年变化,并进行了详细的分析和讨论。结果表明,改造后的POM可较好地模拟出南海海温的年变化特征,其模拟性能随季节而有不同。文中对模拟中存在的不足之处也进行了讨论。     

热带印度洋秋季偶极子模态与南海夏季风强度变化的关系

利用多年的Reynolds月平均海表温度资料和NCEP／NCAR全球大气再分析资料，采用经验正交函数（EOF）分析和滑动相关方法，研究了热带印度洋秋季偶极子模态和南海夏季风强度变化的关系。结果表明：（1）热带印度洋秋季海表温度距平（SSTA）的主要模态是全区一致型和偶极子（IOD）型，全区一致型模态主要代表了秋季SSTA全海盆一致的年代际及其以上时间尺度的变化，IOD型模态主要反映热带印度洋秋季SSTA年际时间尺度的变化。（2）当前期秋季热带印度洋存在正（负）IOD模态时，南海的夏季风强度减弱（增强）。二者年际变化的负相关关系在长期趋势的冷位相期不显著，而在暖位相期显著。（3）当南海夏季风强度增强（减弱）时，后期秋季热带印度洋出现正（负）IOD模态。二者年际变化的正相关关系在长期趋势的冷、暖位相期显著，在冷、暖位相转换期前后不显著。     

PRELIMINARY STUDY OF RELATIONSHIP BETWEEN INTERANNUAL VARIATIONS OF SST IN SOUTH CHINA SEA AND TROPICAL INDIAN OCEAN AND SOUTH CHINA SEA MONSOON OUTBREAK

Conclusions are divided regarding the role of the variations of thermodynamics in the monsoon activity for the South China Sea region. In this study, primary eigenvectors are studied for the SSTA from East Asia to the tropical eastern Indian Ocean in May. The results show that temperature anomalies that center on Sumatra are closely related with the outbreak of the South China Sea monsoon. When the SST is warmer (cooler) than average year, it is likely that the monsoon set in late (early). It may be caused by the changes in meridional difference in thermodynamics between the Indochina Peninsula and its southern tropical oceans. Studying the temporal and spatial evolution of primary eigenvector distribution of the SSTA in the South China Sea-tropical eastern Indian Ocean from winter to summer, we find that the temperature anomalies that center around Sumatra in late spring and early summer can be traced back to the variations of the SST fields in the South China Sea in the preceding winter. Being well associated with the outbreak of the South China Sea monsoon, the latter is a signifi-cant index for it. The work helps understanding the atmospheric and oceanic background against which the South China Sea monsoon breaks out and behaves.     

南海-热带东印度洋海温年际变化与南海季风爆发关系的初步分析

对５月东亚至热带东印度洋表面温度距平主要特征向量场的分析表明，以苏门答腊为中心的热带海洋温度异常与南海季风爆发有密切关系。当该海域海温较常年偏暖（冷）时，南海季风爆发往往迟（早），它可能是通过影响中南半岛与其南方热带海洋之间经向热力差异的变化来实现的。分析了从冬到夏南海－热带东印度洋海温距平主要特征向量场的时空演变，末夏初以苏门答腊为中心的热带海温距平场特征可以追溯到冬季南海海温场的变化，后者与南     

NUMERICAL SIMULATION OF THE INFLUENCE OF INDIAN OCEAN DIPOLE ON CLIMATIC VARIATIONS OVER EAST ASIAN MONSOON REGION DURING EQUATORIAL EAST PACIFIC OCEAN SSTA

1 INTRODUCTION In the recent years, more and more researches have shown that the effect of Tropical Ocean is very evident in the process of ocean-air interaction; Sea-Surface Temperature Anomaly (SSTA) takes on global configuration and SSTA in different areas are interrelated and also have their respective characteristics. The SSTA over Indian Ocean and Pacific Ocean are interrelated. WU et al.[1] and MENG et al.[2] indicated that the evident positive correlation of inter-annual…     

南海各月月平均海流场的数值模拟

本文用一个区域三维、自由表面、斜压海洋模式对南海全年各月的三维平均流场进行了数值模拟，模拟得到的环境特征与己有的实测资料十分相近，这表明该模拟结果是可信的，该数值模拟也是成功的。     

南海海洋站观测海气热通量的时间演变特征

为探索西沙和南沙海气热通量时间演变特征,用海洋站观测资料计算了1998年南海夏季风爆发前后,海气界面热量交换值及海面热收支年循环。结果表明：季风爆发前,西沙海气界面热量交换较弱,水汽通量较小,以海洋获得热量为主;季风爆发后,海气界面热量交换接近平衡。南沙全年主要是海洋对大气加热。南沙和西沙海面吸收短波辐射年周期特征明显,极大值出现在冬半年。西沙海面潜热通量存在半年周期特征,极大值也是出现在冬半年。结论：冬半年海面热通量变化对翌年的季风将产生重要影响。     

RELATIONSHIPS BETWEEN AUTUMN INDIAN OCEAN DIPOLE MODE AND THE STRENGTH OF SCS SUMMER MONSOON

Based on 1948 - 2004 monthly Reynolds Sea Surface Temperature (SST) and NCEP/NCAR atmospheric reanalysis data, the relationships between autumn Indian Ocean Dipole Mode (IODM) and the strength of South China Sea (SCS) Summer Monsoon are investigated through the EOF and smooth correlation methods. The results are as the following. (1) There are two dominant modes of autumn SSTA over the tropical Indian Ocean. They are the uniformly signed basin-wide mode (USBM) and Indian Ocean dipole mode (IODM), respectively. The SSTA associated with USBM are prevailing decadal to interdecadal variability characterized by a unanimous pattern, while the IODM mainly represents interannual variability of SSTA. (2) When positive (negative) IODM exists over the tropical Indian Ocean during the preceding fall, the SCS summer monsoon will be weak (strong). The negative correlation between the interannual variability of IODM and that of SCS summer monsoon is significant during the warm phase of long-term trend but insignificant during the cool phase. (3) When the SCS summer monsoon is strong (weak), the IODM will be in its positive (negative) phase during the following fall season. The positive correlation between the interannual variability of SCS summer monsoon and that of IODM is significant during both the warm and cool phase of the long-term trend, but insignificant during the transition between the two phases.     

夏季季节内振荡对西北太平洋台风活动的影响

利用夏季季节内振荡(Boreal Summer Intraseasonal Oscillation, BSISO)指数和台风密集度分析了夏季季节内振荡和西北太平洋台风活动的关系。台风密集度定义为一天内500 km范围内台风出现的概率,与台风经纬度位置相比,台风密集度可更灵活地表达台风生成及移动特征。结果表明夏季季节内振荡对台风活动有明显的调制作用。当夏季季节内振荡指数1(BSISO1)处于第1、5、6、7、8位相时,南海及菲律宾以东海域台风活动明显增强;当夏季季节内振荡指数2(BSISO2)处于第2、3、4位相时,西北太平洋台风活动也明显增强。当夏季季节内振荡处于这些位相时,台风活动增强与南海及菲律宾以东海域环流气旋式异常、对流活动正异常相一致。      

南海-西太平洋春季对流10~30天振荡强度对南海夏季风爆发早晚的影响

采用NCEP再分析资料,揭示了南海-西太平洋春季对流存在显著的10~30天振荡周期。在年际尺度上,南海-西太平洋春季对流10~30天振荡强度（简称SCSWP_SISO）与南海夏季风爆发日期存在显著的负相关关系。当春季菲律宾和西太平洋海温偏高、赤道太平洋中部及以东地区海温偏低时,索马里、110 °E越赤道气流会加强,南海-西太平洋偏西风加强,产生异常气旋性环流,垂直上升运动增强,水汽异常偏多,东西风切变增强,有利于SCSWP_SISO增强。而SCSWP_SISO增强时,有由南往北、自西向东的异常气旋传播,从而减弱低层副热带高压使之较早撤出南海,南海夏季风得以较早爆发。反之亦然。在不同的年代际背景下,SCSWP_SISO经历了偏弱、较弱和偏强的变化,但影响其变化的因子并不完全一致。在第一阶段（1958—1976年）,主导因子是南海-西太平洋冷的海温与异常下沉运动、异常减弱的水汽-对流条件。在第二阶段（1977—1993年）,主导因子为中东太平洋异常偏冷的海温以及局地异常减弱的风场垂直切变。在第三阶段（1994—2011年）,主导因子为热带海温的整体偏暖、风场垂直切变的增强以及水汽-对流的加强。但随着SCSWP_SISO的年代际增强,其与南海夏季风爆发日期的相关关系却呈现下降趋势。      

SEASONAL AND INTER-ANNUAL VARIABILITY OF THE SOUTH CHINA SEA WARM POOL AND ITS RELATION TO THE SOUTH CHINA SEA MONSOON ONSET

The South China Sea warm pool interacts vigorously with the summer monsoon which is active in the region. However, there has not been a definition concerning the former warm pool which is as specific as that for the latter. The seasonal and inter-annual variability of the South China Sea warm pool and its relations to the South China Sea monsoon onset were analyzed using Levitus and NCEP/NCAR OISST data. The results show that, the seasonal variability of the South China Sea warm pool is obvious, which is weak in winter, develops rapidly in spring, becomes strong and extensive in summer and early autumn, and quickly decays from mid-autumn. The South China Sea warm pool is 55 m in thickness in the strongest period and its axis is oriented from southwest to northeast with the main section locating along the western offshore steep slope of northern Kalimantan-Palawan Island. For the warm pools in the South China Sea, west Pacific and Indian Ocean, the oscillation, which is within the same large scale air-sea coupling system, is periodic around 5 years. There are additional oscillations of about 2.5 years and simultaneous inter-annual variations for the latter two warm pools. The intensity of the South China Sea warm pool varies by a lag of about 5 months as compared to the west Pacific one. The result also indicates that the inter-annual variation of the intensity index is closely related with the onset time of the South China Sea monsoon. When the former is persistently warmer (colder) in preceding winter and spring, the monsoon in the South China Sea usually sets in on a later (earlier) date in early summer. The relation is associated with the activity of the high pressure over the sea in early summer. An oceanic background is given for the prediction of the South China Sea summer monsoon, though the mechanism through which the warm pool and eventually the monsoon are affected remains unclear.