西北太平洋西边界流系源区的数值模拟研究

采用POM模式对2005年西北太平洋西边界流系源区进行了数值模拟.针对该海区海表热通量与POM模式匹配困难的问题,在模拟过程中,分别采用由同化AMSR卫星资料插值得到的日平均海表温度场以及由NCEP资料得到的海表净热通量与长、短波辐射通量两种方案来进行海表热强迫.通过与SODA资料的分析结果对比,POM模式模拟结果较好地显示出北赤道流,黑潮源区及棉兰老海流的基本特征,两处断面流速与实际探测资料较为吻合;高度场模拟结果与实况较为一致,但0.9m水位高度线范围呈缩小-放大-缩小-放大的季节性震荡与实况中维持稳定存在一定差异;海温模拟结果与月平均的SODA资料总体一致,但在春夏两季温度略高.     

西北太平洋热带风暴年生成数与早期洋盆尺度海温异常的关系

利用JTWC提供的热带气旋最佳路径资料库资料和JEDAC的海表温度观测资料，分析了1955年1月到2000年12月西北太平洋热带风暴年生成频次的长期变化及其与太平洋海温的关系.西北太平洋热带风暴年生成频次长期变化的基本特征是，最多生成频数月份有提早的趋势，除了阶段性变化外还存在增多的趋势.太平洋海温与西北太平洋热带风暴生成频次之间没有同期的相关关系，但年初赤道东西太平洋和中高纬度北太平洋的海温与当年和其后数月热带风暴生成频次有显著的相关关系.前者反映的是年际时间尺度上赤道附近东西部El Nio海温异常模态对热带风暴生成数的影响，后者反映的是年代际时间尺度上北太平洋海温异常对热带风暴数的影响.考虑两个时间尺度海温变化建立的年初海温与当年风暴频次的回归相关高达0.77.     

中纬度海温异常与环流变化的数值模拟

本文采用二维纬向平均模式,通过模拟试验,研究西太平洋中纬度海域海温异常对环流变化以及我国东部江淮、华北平原汛期降水的影响。按季节不同把海温异常分为南冷北暖型和南暖北冷型。结果表明前期海温异常,其后3—5个月西太平洋副高位置明显变化。例如,春季南冷北暖型异常分布(20°—35°N偏冷,35°N以北偏暖)则夏季副高增强,其脊线位置偏北,长江流域夏季(7—8月)偏旱,而华北地区偏涝。反之,得到相反的结果。     

云南地区降水与太平洋海温的奇异值分解分析

利用奇异值分解法（ＳＶＤ）分析了云南２１个站各月降水距平与北太平洋海温的相关关系,得到了奇异向量,对贡献原前２个奇异向量进行分析,结果表明：①平均意义上,秋 季海温与云南各月降水存在显著的相关关系;②秋冬季热带东太平洋海温对型年春末盛夏云南中部地区的降水有显著的影响。③秋冬季的热带中东太平洋海温与前一年春末和盛夏降水也存在明显的相关关系。     

黑潮和南海北部海流相互关联的数值模拟研究

根据北太平洋环境区域性模式的计算结果研究了黑潮和南海北部上层海流的相互关联问题。计算结果表明：在巴士海峡南部一年中大部分时间都有一部分黑潮水流入南海，其中一部分在南海呈一反气旋式弯曲，然后在巴士海峡北部又流回到黑潮主干；另一部分与南海北部的一个气旋式涡旋的北翼一起向西流动，有时可以一起 流到南海的内部海域。６月份南海北部并不存在气旋式涡旋，在巴士海峡南部进入南海的水，只呈反气旋式流动，从巴士海峡北     

西北太平洋温带风暴活动与航线选择

利用１９８７￣１９９６年间发生在东亚及西北太平洋地区的温带旋风暴资料,分析总结了温带风暴的活动规律和形成演变特征,论述了冬半年北太平洋中高纬安全航线的选择,对在航船舶具有实际的应用价值。     

典型海流磁场的数值模拟

我们采用麦克思韦方程计算了典型海流感应产生的磁场强度,并采用该模型模拟了海流的磁场,证实当海流宽度较大时,不能忽略海流感应的磁场。     

Relationship between the tropical cyclone genesis over the Northwest Pacific and the sea surface temperature anomalies

Using the tropical cyclone (TC) data derived from the Joint Typhoon Warning Center (JTWC) and the sea surface temperature data derived from the Joint Environmental Data Analysis Center (JEDAC) at the Scripps Institute of Oceanography from January 1955 to December 2000, we analyzed the relationship between the TC genesis over the Northwest Pacific (NWP) and the sea surface temperature anomalies (SSTA) over the Pacific basin. A long-term trend indicated that the highest frequency of monthly TC genesis appeared earlier and the annual genesis sum increased gradually during the last half century with some oscillations. No significant synchronous correlation was found between the NWP TC events and the SSTA over the Pacific basin, while the annual sum of TC genesis was closely related with the SSTA averaged from the first three months (January, February and March) of the year in the equatorial western and eastern Pacific and over mid-high latitudes of the North Pacific. The results implied that there are an interannual El Nio SSTA mode in the equatorial western and eastern Pacific and an interdecadal SSTA mode in the northern Pacific, which affected the TC genesis. A regression analysis between the first three-month SSTA and the annual TC sum based on two time scales was conducted. The correlation coefficient between simulated and observed TC sums reached a high value of 0.77.     

Relationship between the tropical cyclone genesis over the Northwest Pacific and the sea surface temperature anomalies

Using the tropical cyclone (TC) data derived from the Joint Typhoon Warning Center (JTWC) and the sea surface temperature data derived from the Joint Environmental Data Analysis Center (JEDAC) at the Scripps Institute of Oceanography from January 1955 to December 2000, we analyzed the relationship between the TC genesis over the Northwest Pacific (NWP) and the sea surface temperature anomalies (SSTA) over the Pacific basin. A long-term trend indicated that the highest frequency of monthly TC genesis appeared earlier and the annual genesis sum increased gradually during the last half century with some oscillations. No significant synchronous correlation was found between the NWP TC events and the SSTA over the Pacific basin, while the annual sum of TC genesis was closely related with the SSTA averaged from the first three months (January, February and March) of the year in the equatorial western and eastern Pacific and over mid-high latitudes of the North Pacific. The results implied that there are an interannual El Nio SSTA mode in the equatorial western and eastern Pacific and an interdecadal SSTA mode in the northern Pacific, which affected the TC genesis. A regression analysis between the first three-month SSTA and the annual TC sum based on two time scales was conducted. The correlation coefficient between simulated and observed TC sums reached a high value of 0.77.     

Linkage between the Asian-Pacific Oscillation and the sea surface temperature in the North Pacific

The linkage between the Asian-Pacific Oscillation (APO) and the sea surface temperature (SST) in the North Pacific during the summertime (June-August) is preliminarily investigated through an analysis of observed data.It is found that APO is significantly and positively correlated to the North Pacific SST,with the correlation coefficient being 0.58 on the interannual timescale during the period 1954-2003,which suggests that a strong (weak) APO corresponds to high (low) SST in the North Pacific.Their in-phas...     

西北太平洋温盐分布的时空尺度分析

为了更清晰地了解西北太平洋的温盐分布特征,基于全球实时海洋观测计划(Argo)浮标观测剖面,利用自相关函数方法,对西北太平洋海域(选取范围为120°E~160°W,10~40°N)温盐分布的时空尺度进行了分析,并通过高斯函数拟合得到了温盐的时空去相关尺度。研究表明,自相关函数随季节和深度发生变化,各层的自相关函数值随着空间增大而降低。表层,夏季温度的空间去相关尺度比冬季大,但时间去相关尺度小;次表层,夏季温度的自相关函数随空间增大迅速递减,空间去相关尺度比冬季小;深层,夏季和冬季的温度时空尺度相近。盐度的季节性变化较温度要小,但盐度的空间变化尺度比温度要大,而时间变化尺度则比温度小。2种要素的信噪比均大于2,可以用来指导精细化观测布网的采样间隔。     

东北夏季降水的时间变化特征及其与太平洋海温的相关关系

利用中国降水逐日站点观测资料以及HadISST海温资料,分析了1961-2010年东北地区70个观测站夏季降水的变化特征以及太平洋海温对东北夏季降水的可能影响。结果表明：东北夏季降水近50a来呈现下降趋势,具有多阶段性,在60年代以及80-90年代存在明显的突变;在1986-1985年以及1986-2010年2个阶段,热带外太平洋与热带太平洋春季和夏季海温都存在与东北夏季降水的相关关键区,两个阶段相关性显著不同甚至相反,是1961-2010年东北夏季降水与太平洋海温总体相关性较弱的原因。东北夏季降水与太平洋海温的相关性可能与海温冷暖背景有关系：在暖的海温背景下,东北降水与热带太平洋海温呈现显著的正相关;而对于热带外太平洋,暖的海温背景下,两者为负相关,冷的海温背景下,两者为正相关,尤其表现在春季,因此太平洋春季海温异常对于东北夏季降水预测有较好的指示意义。     

Interdecadal variation of tropical cyclone activity in association with summer monsoon, sea surface temperature over the western North Pacific

Based on geographic division over the western North Pacific (WNP), the interdecadal relationships between summer monsoon, sea surface temperature (SST) and tropical cyclones activity (including number, track and intensity) are examined. In the past several decades, the western Pacific subtropical high (WPSH) and tropical westerlies contribute to the interdecadal variation of TC number in the northwest and southeast of WNP respectively. The increased TC occurrence density to the east of Philippines related to TC track appears during the 1990s, in terms of both steer flow induced by WPSH and genesis location. From the interdecadal viewpoint, the tendency of TC intensity, measured by averaged accumulated cyclone energy, does well agree with that of SST, implying that SST plays an important role in TC intensity. Supported by Special Scientific Research Project for Public Interest (Grant No. GYHY200806009) and National Basic Research Program of China (Grant No. 2009CB421505)     

Positive feedback of winter ocean-atmosphere interaction in Northwest Pacific

Associated with East Asia Trough in the upper layer in winter, the Aleutian Low is the predominant atmos- pheric activity center in North Pacific. Previous re- searches on interannual or decadal variability of Aleu- tian Low[1―4] found that the Aleutian …     

Simulation of sea surface temperature changes in the Middle Pliocene warm period and comparison with reconstructions

The Middle Pliocene (ca 3.12–2.97 Ma) is a recent warm period in the Earth’s history. In many respects, the warmth of the Middle Pliocene is similar to the probable warm situation of the late 21st century predicted by climate models. Understanding the Middle Pliocene climate is important in predicting the future climate with global warming. Here, we used the latest reconstructions for the Middle Pliocene—Pliocene Research Interpretation and Synoptic Mapping (PRISM) version 3—to simulate the Middle Pliocene ...     

Relationship between Hadley circulation and sea ice extent in the Bering Sea

The linkage between Hadley circulation （HC） and sea ice extent in the Bering Sea during March-April is investigated through an analysis of observed data in this research. It is found that HC is negatively correlated to the sea ice extent in the Bering Sea, namely, strong （weak） HC is corresponding to less （more） sea ice in the Bering Sea. The present study also addresses the large-scale atmospheric general circulation changes underlying the relationship between HC and sea ice in the Bering Sea. It follows that a positive phase of HC corresponds to westward located Aleutian low, anomalous southerlies over the eastern North Pacific and higher temperature in the Bering Sea, providing unfavorable atmospheric and thermal conditions for the sea ice forming, and thus sea ice extent in the Bering Sea is decreased, and vice versa. In addition, it is further identified that East Asian-North Pacific-North America teleconnection may play an important role in linking HC and changes of atmospheric circulations as well as sea ice in the Bering Sea.     

湛江港海域台风浪模拟研究

利用第3代近岸海浪数值模式对影响南海湛江港海域的3次台风浪过程进行了模拟研究。结果表明：由藤田台风模型同化相应时刻的台风要素、NCAR网格点资料、单站观测资料后提供模式所需风场，利用自嵌套方式提供模式所需波谱边界条件的处理方法，对这3次台风浪的模拟来说，是较为理想的，此方案可为该海域台风浪的模拟预报提供较好的参考。