导致西太平洋海温异常的主要因素研究

通过对不同区域海表面温度(SST)资料做超前/滞后相关性分析,研究导致西太平洋SST异常的主要因素。基于东、西太平洋相互作用理论和印度洋电容器效应理论,将热带西太平洋SST异常的变化分别与热带东太平洋和印度洋SST异常做超前/滞后相关性分析,得到每个格点与强迫场之间相关性最显著的月份,从时间的角度研究西太平洋SST异常变化与东太平洋和印度洋之间的关系。按照上述两种理论,由于海洋的比热大,热响应时间较长,西太平洋SST变化应滞后于东太平洋或印度洋2~3个月。分析结果显示,在El Nino和La Nina事件下,西太平洋SST异常变化均超前于东太平洋1~2个月时相关性最显著;同时,西太平洋SST异常变化超前于印度洋3~4个月时相关性最显著。这表明热带东太平洋和印度洋都不是导致西太平洋SST异常变化的主要因素,西太平洋SST异常可能由多种因素共同作用所导致。     

西太平洋海温和北极海冰异常对大气环流的影响

利用九层菱形截断１５波的全球大气环流谱模式,对赤道西太平洋海表温度,北极海冰及综合异常精形在北半球夏季大气环流中的作用进行了一系列数值试验和分析。结果表明：赤道西太平洋海表温度的异常变化与北极海冰面呼焦异均可显著影响大气环流,但海冰异常对低纬大气环流的影响远小于西太平洋的海温异常的影响。对全球大气环流异常形成机制的讨论,表二维Ｒｏｓｓｂｙ波开的传播及外强迫引起的大气内部动力学过程虽夏季大气环流异常     

西南印度洋海温异常影响亚洲夏季风爆发的数值试验

利用中国科学院大气物理研究所的9层大气环流模式(IAP9—AGCMⅡ)作了西南印度洋海温月异常对亚洲夏季风爆发影响的数值试验。试验结果表明，当该海域1—3月份的海温出现异常增暖时，印度夏季风和东亚夏季风的爆发均较平常晚，反之，二者的建立均较平常早；该海域1—3月份的海温异常对亚洲季风区的降水也有明显的影响。     

冬春海温异常对东亚初夏季风环流的影响

用ＯＳＵ的两层大气环流模式进行了热带西太平洋冬春海温异常对东亚初夏（５月）季风环流影响的数值试验．结果表明：①海温的负距平引起西太平洋副热带高压脊南落和西伸，东亚热带季风环流减弱，我国西南和华南地区的降水增加；②海温的正距平引起西太平洋副热带高压明显减弱，西太平洋的赤道西风加强，我国西南和华南地区的降水减少     

大气对海温构型及转换过程的响应——副高进退及异常机理讨论

用动力学分析和数值计算的方法讨论了大气对热带太平洋几咎典型海温分布构型及其转换过程的热力强迫响应。结果表明：持续的海温热力强迫可以很快地激发出稳定的大气平稳态响应,Ｌａ Ｎｉｎａ（Ｅｌ Ｎｉｎｏ）期间的大气位势应分别利于夏季西太平洋副高增强（减弱）和位置偏北（偏南）。不同构型的海温转换及转换过程的快慢直接影响大气位势的响应形式,转换过程的异常可能将导致导致夏季西太平洋副高活动异常。     

热带海温异常与南海夏季风建立迟早的初步研究

利用NCEP再分析的海表温度场、风场、高度场的格点资料,应用合成和相关分析等方法,初步探讨了热带印度洋和热带太平洋海温异常与南海夏季风建立的关系.研究结果表明,热带印度洋和热带太平洋海温异常在有些年份并不同号,从而对南海夏季风建立迟早的影响并不完全一致.进一步分析表明,热带印度洋和热带太平洋海温异常可能是通过影响热带地区Walker环流建立和加强,进而南海夏季风建立的迟早.     

云南林火重灾年与太平洋海温异常变化关系的研究

运用异常度分析技术,研究发现如果东太平洋部分海域的某些年份海温升高,而后的第3年海温又偏低,则紧随而至的云南防火季可能是森林火险重灾年.另外,El Nino发生后的第3、4年云南就很可能具有爆发森林大火的气候背景,这为云南森林火险的长期趋势预报提供了一种方法.     

黑潮弯曲时的北太平洋冬季海温异常对大气低频振荡的影响

利用中科院大气物理研究所开放实验室ＩＡＰ－ＡＧＣＭ（二层大气环流模式），针对黑潮弯曲时的北太平洋冬季表层海温（ＳＳＴ）异常进行八个月的数值积分试验。试验结果表明：黑潮弯曲时北太平洋冬季ＳＳＴ异常对大气低频振荡的影响具有明显的３０－６０ｄ振荡的特征；在北半球的３０－６０ｄ振荡，大部分地区为向西传播，在南半球则为向东传播；其经向传播较为复杂，在１２０℃剖面上以向南传播为主；热带地区受此ＳＳＴ异常的影响     

用简单海气耦合模式研究西太平洋暖池的形成机制及其对大气扰动的影响

用第一部分建立的简单海气耦合模式，研究了西洋洋暖池的形成过程及其对大气扰动的影响。模式可以较好地模拟出热带太平洋海温“西高东低”的分布，以及“暖池”附近ＳＳＴ的水平梯度较小等特征。在垂直方向上海洋混合层深度关于赤道呈冷对称的“马鞍”型分布特征也可以从理论上和数值模拟的结果中得到证实。模式中“暖池”形成的时间尺度大约料年多，大气中凝结潜热的释放有利于“暖池”的快速形成，提高凝结潜热的释放的效率，“暖     

与热盐环流相关的海温异常对大西洋沿岸气候影响的诊断模拟研究

THC（热盐环流）的变化对全球气候的影响在大西洋地区最为显著,Manabe利用淡水强迫THC引起海温变化的信号也主要集中在大西洋,并呈dipole（耦极）模态分布．文中根据Manabe淡水强迫THC实验结果,给定北大西洋冷,南大西洋暖的海温距平分布代表弱THC,以相反海温距平分布代表强THC,利用大西洋这两种异常海温来驱动大气环流模式,研究这两种海温异常分布所代表的THC强弱变化对大西洋沿岸气候的影响,并且选出5个降水对THC变化敏感的地区,利用这些地区观测的降水资料拟合一个反映THC强弱变化的综合指数THCI,该综合指数能有效反映近100年THC变化的主要特征。     

Interannual and interdecadal variabilities in SST anomaly over the eastern equatorial Pacific

The global sea surface temperature (SST) anomaly data from 1950 to 1996 were used to analyze spatial characters of interdecadal SST variations. A wavelet transform was made for the equatorial eastern Pacific SST anomaly time series. Results show that there are three remarkable timescale SST variations: 130-month interdecadal variation, 57-month interannual variation and 28-month quasi-2-a variation. Based on this result, an El Nino event was predicted in the early part of 1997.     

Interdecadal shift in the western North Pacific Summer SST anomaly in the late 1980s

An interdecadal shift in summer (June―August) sea surface temperature (SST) variations during the period of 1968―2002 was identified in the late 1980s, which is characterized by a phase alternating from negative to positive phases of the leading mode of the empirical orthogonal function (EOF) analysis of the summer monthly mean SST in the Pacific domain 100°―180°E and 0°―40°N, accounting for 30.5% of the total variance. During the period of 1968―1987, the leading mode with a mean negative phase state (mean standard deviation = ?0.586) controlled SST variability in the western North Pacific. Correspondingly, negative SST anomalies occupied the western North Pacific south of Japan and Chinese marginal seas. During the period of 1988―2002, the leading mode shifted to its strong positive polarity (mean standard deviation = 0.781), thus positive SST anomalies appeared in the western North Pacific. Accompanied by the interdecadal shift in summer mean SST, summer mean rainfall increased in southern and southeastern China during the late period, particularly in southeastern China where increase in summer mean rainfall exceeded 40 mm, at the 0.05 significance level.     

北太平洋卫星测高大地水准面异常和海底测深的模型拟合(英文)

卫星测高资料的利用问题是一个新的研究课题.作者根据自己计算的卫星测高大地水准面异常图,采用模型拟合法,求得了一些岩浆负载的参数,这对于研究它们的起源和演化是很有用的.特别是其中的Hess 隆起的参数具有重要意义,它可能暗示一种新的海底生成机制.     

Indian Ocean temperature dipole and SSTA in the equatorial Pacific Ocean

The observed sea surface temperature (SST) data of recent 100 years are analyzed and the existence of the Indian Ocean temperature dipole in the equatorial region is exposed further. It is very clear that the amplitude of the positive phase (higher SST in the west and lower SST in the east than normal) is larger than that of the negative phase (higher SST in the east and lower SST in the west). The dipole is stronger in September-November and weaker in January-April than in other months and it also appears obviously inter-annual and inter-decadal variations. Although the Indian Ocean dipole in the individual year seems to be independent of ENSO in the equatorial Pacific Ocean, in general, the Indian Ocean dipole has obviously negative correlation with the Pacific Ocean dipole (similar to the inverse phase of ENSO mode). The atmospheric zonal (Walker) circulation over the equator is fundamental to relate the two dipoles to each other.     

暖池区1.53 Ma以来上层海水变化的颗石藻证据

对位于西太平洋暖池区核心的大洋钻探计划(ODP)807站1.53Ma以来深海沉积样品进行了颗石藻化石分析,通过Florisphaeraprofunda数量百分比讨论了营养跃层深度变化的趋势,并计算了初级生产力.结果表明1.53Ma以来暖池核心区海水营养跃层经历了明显变化:从1.53~0.9Ma,营养跃层深度逐渐变浅;自0.9Ma起营养跃层开始变深并保持到0.48Ma;0.48~0.28Ma之间是营养跃层深度明显变浅的一个时期,在这以后营养跃层逐渐变深.根据颗石藻得出的海水营养跃层变化与初级生产力变化基本一致,也与根据浮游有孔虫转换函数得出的温跃层深度变化趋势基本一致.对比ODP807站和南海ODP1143站F.profunda数量百分比和初级生产力变化曲线,两站在0.9Ma以前变化的趋势相反,而0.9Ma以后基本一致.说明0.9Ma以前暖池核心地区与边缘区上层海水的变化有差异,而0.9Ma以后两者则趋同.     

Modeling studies on the changes of the Subtropical High over the Western Pacific during the last 100 years

Intensity index series of Subtropical High over the Western Pacific was constructed according to modeling results by using of CCM3.6 atmospheric model with climatologically SST forcing for 30 years, and with observed SST forcing from 1900 to 2000. The index series constructed by modeling closely correlated to the observations for 1951-1999 (c.c. 0.72) and to the statistically reconstructed one for 1900-1950 (c.c. 0.51). The index series for 1900-1999 showed significant 80 a and 40 a periodicity. A minimum of persistence in seasonal variations of the index occurred in Autumn, which was called "Autumn Barrier". It may relate to the "Spring Barrier", found in the seasonal variations of SST over the Eastern Equatorial Pacific. The increasing trend shown in the index series for the 20th century may associate with the global warming caused by enhancement of greenhouse effect.     

西北太平洋热带气旋气候特征及其变化研究的若干进展

为了对我国气象工作者全面了解和参与热带气旋的研究有所帮助,在大量阅读和调研的基础上,介绍了近20年西北太平洋热带气旋活动在季节、年际和年代际尺度上研究的若干主要成果.重点阐述了EN-SO与热带气旋的关系,温室效应热带气旋的数值模拟和观测研究等的最新动态.     

Foreshowing of the Western Pacific tropical cyclone track to PM10 air pollution episode in the Beijing area

By utilizing the air quality monitoring data and the NCEP reanalysis data, the relationship between the PM10 air pollution episode and synoptic situation is analyzed in the Beijing area. It is interesting to find that PM10 air pollution episode in and around the Beijing area is correlated with the Western Pacific tropical cyclone track to some extent, namely when a tropical cyclone lands southward to the Changjiang River, PM10 air pollution episode is not easy to take place generally in the Beijing area; but when a tropical cyclone moves northward and finally lands at the Korea Peninsula or the Japanese mainland, and under this condition the Beijing area is generally controlled by weak high or weak low for several days, PM10 air pollution episode often takes place in one day or several days. Above findings indicate that predicting the Western Pacific tropical cyclone track can foretell whether or not PM10 air pollution episode takes place in the Beijing area, which can offer a technique for urban air quality prediction and air pollution source management in the Beijing area. Supported by Knowledge Innovation Project of the Chinese Academy of Sciences (Grant No. KZCZ2-YW-219) and Frontier Research of IAP of Chinese Academy of Sciences (Grant No. 8-070204)