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1.
Using the 1980-2010 winter GODAS oceanic assimilations, study is conducted of the winter heat content (HC) established in the subsurface layer (5 to 366 m in depth) over the western Pacific warm pool (WP), followed by investigating the HC spatiotemporal characteristics, persistence and the impacts on the climate anomalies of neighboring regions. Results are as follows: 1) the pattern of integral consistency is uncovered by the leading EOF1 (PC1) mode of HC interannual variability, the year-to-year fluctuation of the time coefficients being well indicative of the interannual anomaly of the WP winter subsurface-layer thermal regime. The HC variation is bound up with ENSO, keeping pronounced autocorrelation during the following two seasons and more, with the persistence being more stable in comparison to SSTA in the equatorial middle eastern Pacific; 2) the winter HC anomalies produce lasting effect on the WP thermal state in the following spring and summer and corresponding changes in the warm water volume lead to the meridional transport and vertical exchange of warm water, which exerts greater impacts upon the sea surface temperature/heat flux over the warm pool per se and neighboring regions, especially in the Philippine Sea during the posterior spring and summer; 3) the increase in the winter HC corresponds to the spring OLR decrease and richer precipitation over the waters east to the Philippine Sea and the resultant convective heating anomalies are responsible for the rise of geopotential isobaric surfaces over tropical and subtropical western North Pacific, thereby producing effect on the western Pacific subtropical high (anomaly). Subsequently, the sea-surface heat flux exchange is intensified in the warm pool, a robust anomalous cyclone shows up at lower levels, air-sea interactions are enhanced and abnormal convective heating occurs, together making the winter HC anomalies even more closely associated with the variation in the summer subtropical high. As a result, the WP winter HC can be used as an effective predictor of the variation in spring/summer western Pacific subtropical high and the strength of summer monsoon over the northwestern Pacific. 相似文献
2.
In this paper,climatic features of sea temperature of western Pacific warm pool and therelationship with sea surface temperature (SST) of its adjacent regions are analyzed based on theobserved sea temperature on vertical cross section along 137°E in western Pacific,the monthlymean SST of Xisha Station in South China Sea and the global monthly mean SST with resolution of1°×1°(U.K./GISST2.2).The results indicate that (1) in a sense of correlation.SST of westernPacific warm pool can represent its sea subsurface temperature from surface to 200 m-depth level inwinter,and it can only represent sea temperature from surface to 70 m depth in summer.The seasubsurface temperature anomaly of warm pool may be more suitable for representing thermalregime of western Pacific warm pool.The sea subsurface temperature of warm pool has acharacteristic of quasi-biennial oscillation.(2)Warm pool and Kuroshio current are subject todifferent ocean current systems (3)Furthermore,the relationship between SST of Xisha Stationand SST of warm pool has a characteristic of negative correlation in winter and positive correlationin summer,and a better lag negative correlation of SST of Xisha Station with sea subsurfacetemperature of warm pool exists.(4)Additionally,oscillation structure of sea temperature like “aseesaw” exists in between warm pool and Regions Nino3 and Nino4.January (June) maximum(minimum) sea subsurface temperature anomaly of warm pool may serve as a strong signal thatindicates maturity phase (development phase) of La Nina (El Nino) event,it also acts as a strongsignal which reveals variations of SST of Regions Nino3 and Nino4. 相似文献
3.
Typhoon Hato (2017) went through a rapid intensification (RI) process before making landfall in Zhuhai, Guangdong Province, as the observational data shows. Within 24 hours, its minimum sea level pressure deepened by 35hPa and its maximum sustained wind speed increased by 20m s-1. According to satellite observations, Hato encountered a large area of warm water and two warm core rings before the RI process, and the average sea surface temperature cooling (SSTC) induced by Hato was only around 0.73℃. Air-sea coupled simulations were implemented to investigate the specific impact of the warm water on its RI process. The results showed that the warm water played an important role by facilitating the RI process by around 20%. Sea surface temperature budget analysis showed that the SSTC induced by mixing mechanism was not obvious due to the warm water. Besides, the cold advection hardly caused any SSTC, either. Therefore, the SSTC induced by Hato was much weaker compared with that in general cases. The negative feedback between ocean and Hato was restrained and abundant heat and moisture were sufficiently supplied to Hato. The warm water helped heat flux increase by around 20%, too. Therefore, the warm water influenced the structure and the intensity of Hato. Although there might be other factors that also participated in the RI process, this study focused on air-sea interaction in tropical cyclone forecast and discussed the impact of warm water on the intensity and structure of a tropical cyclone. 相似文献
4.
The influence of the tropical Indo-Pacific Ocean heat content on the onset of the Bay of Bengal summer monsoon(BOBSM) onset was investigated using atmospheric data from the NCEP and ocean subsurface temperature data from the Japan Metorology Agency(JMA).Results showed that the onset time of the BOBSM is highly related to the tropical Pacific upper ocean heat content(HC),especially in the key region of the western Pacific warm pool(WPWP),during the preceding winter and spring.When the HC anomalies in the WPWP are positive(negative),the onset of the BOBSM is usually early(late).Accompanied by the variation of the convection activity over the WPWP,mainly induced by the underlying ocean temperature anomalies,the Walker circulation becomes stronger or weaker.This enhances or weakens the westerly over the tropical Indian Ocean flowing into the BOB in the boreal spring,which is essential to BOBSM onset.The possible mechanism of influence of cyclonic/anti-cyclonic circulation over the northwestern tropical Pacific on BOBSM onset is also discussed. 相似文献
5.
1 INTRODUCTION The flood period in South China (SC) lasts long and rains heavily. Its relationship with the SST in the near sea has been studied by Chinese meteorologists early. Liang[1] found that the rainfall of Guangdong in warm water years of South China Sea (SCS) is more than in cold water years. Xie et al[2]. analyzed the relations between the rainfall in Guangdong flood period (from April to September) and SST in northwest Pacific, and built prognostic equations for monthl… 相似文献
6.
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. 相似文献
7.
Changing Trends of Daily Temperature Extremes with Different Intensities in China 总被引：1，自引：0，他引：1 
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下载免费PDF全文 By comparing two sets of quality-controlled daily temperature observation data with and without the inhomogeneity test and adjustment from 654 stations in China during 1956-2004 and 1956-2010, impacts of inhomogeneity on changing trends of four percentile temperature extreme indices, including occurrences of cold days, cold nights, warm days, and warm nights with varying intensities, were discussed. It is found that the inhomogeneity affected the long-term trends averaged over extensive regions limitedly. In order to minimize the inhomogeneity impact, the 83 stations identified with obvious inhomogeneity impacts were removed, and an updated analysis of changing trends of the four temperature extreme indices with varying intensities during 1956-2010 was conducted. The results show that annual occurrences of both cold nights and cold days decreased greatly while those of warm nights and warm days increased significantly during the recent 20 years. The more extreme the event is, the greater the magnitude of changing trends for the temperature extreme index is. An obvious increasing trend was observed in annual occurrences of cold days and cold nights in the recent four years. The magnitude of changing trends of warm extreme indices was greater than that of cold extreme indices, and it was greater in northern China than in southern China. Trends for summer occurrence of cold days were not significant. Decreasing trends of occurrences of both cold nights and cold days were the greatest in December, January, and February (DJF) but the least in June, July, and August (JJA), while increasing trends of warm nights were the greatest in JJA. Cold nights significantly decreased from 1956 to 1990, and then the decreasing trend considerably weakened. The decreasing trend also showed an obvious slowdown in recent years for occurrence of cold days. However, increasing trends of warm nights and warm days both have been accelerated continuously since the recent decades. Further analysis presents that the evolution of the trends for occurrences of the four temperature extreme indices was dominated by the changes in northern China. 相似文献
8.
1 INTRODUCTION The ocean is a very important source of heat and water vapor for the atmosphere. Its changes in state are mainly reflected by SST, which varies in high frequency (or called the ENSO variability) and low frequency (or known as interdecadal variability). Studies[1] have shown that the spatial structure for low frequency is much similar to that for high frequency, which is also known as ENSO-like mode. Called “teleconnection”, the anomalous link between the El Ni?o phen… 相似文献
9.
By using a linear and stationary atmospheric model (Luo and Jiang, 1994, Zebiak and Cane,1987) and the initial data coming from Zebiak and Cane (1987), the influence of interaction between shift of warm pool and that of the equatorial convergence zone (ITCZ and SPCZ ) on atmospheric surface stream field and divergence field during 82/83 ENSO is analysed by numerical experiments.The results show that SPCZ is more important than ITCZ in developing phase and mature phase of warm event.The interaction of warm Pool and SPCZ is stronger than that of warm pool and ITCZ in the two phases.SPCZ is as important as ITCZ in the initial phase and decline phase of warm event. 相似文献
10.
An atmospheric general circulation model is used in a series of three experiments to simulate the intraseasonaloscillation in the tropical atmosphere.Analyses of the model daily data show that various physical variables,from sever-al different regions,exhibit fluctuations with a spectral peak between 30 and 60 days.This represents a 30—60 dayoscillation in the tropical atmosphere and possesses several features which are consistent with observations.These in-clude a horizontal structure dominated by zonal wavenumber 1 and a vertical structure which is predominantlybaroclinic.The effect of warm SST (sea surface temperature) anomalies on the 30—60 day oscillation in the tropical atmos-phere is also simulated by prescribing global SST as observed in 1983.This has the effect of weakening the oscillationwhile at the same time the vertical structure becomes less baroclinic.The importance of cumulus convection to the propagational characteristics of this oscillation is demonstrated by acomparison of results based on different parameterizations for convection.In one case,where the maximum convectionover the Pacific is simulated to be too far east,the simulated 30—60 day oscillation shows evidence of westward propa-gation.In the second case,where the convection maximum is located near the observed position in the western Pacific,there is more clearly evidence of eastward propagation.Both results suggest that the location of maximum convection in the Pacific can have an important influence on thestrength,structure and propagation of the 30—60 day oscillation. 相似文献
11.
基于美国哥伦比亚大学Lamont—Doherty地球观象台LDEO（Lamont—DohertyEarth Observatory）海表温度资料和NCEP／NCAR再分析风场资料，分析了1997／1998年El Nino3期间西太平洋暖池海表温度和西风距平的时间演变特征，同时也分析了东太平洋暖池海表温度和北风距平的时间演变特征。结果表明，1997／1998年El Nino3事件期间，西太平洋暖池海表温度变化及异常西风和东太平洋暖池海表温度变化及异常北风都与Nino3指数变化密切相关。将东、西太平洋暖池及异常北风、西风一并结合起来考虑，进一步研究了1997／1998年El Nino3事件发生、发展的可能机制：异常西风驱动西太平洋暖池东端暖水向东伸展直接有利于赤道东太平洋海表温度增加；异常西风激发东传的暖Kelvin波对东太平洋的冷上升流有抑制作用，从而有利于赤道东太平洋海表温度增加；东传的异常西风可以通过埃克曼漂流效应将赤道两侧的海表暖水向赤道辐合从而加强了赤道附近的下沉流，也有利于赤道东太平洋赤道附近海表温度增加。几乎与此同时，北风距平通过产生北风吹流将东太平洋暖池暖水由北向南输送至赤道附近直接导致Nino3区海表温度增加。上述增温因素的叠加作用共同导致了1997／1998年El Nino事件迅速发生、异常强大。 相似文献
12.
From satellite observations and the reanalysis data, the late spring formation of warm water with temperature higher than 30 °C to the southwest of the Philippine Islands (8–18°N, 115–120°E) is investigated. Our analysis suggests that the blockage of the winter monsoon by the Philippine Islands results in this “Luzon warm water” (LWW) to the southwest of the Luzon Island and the “Vietnam cold tongue” (VCT) to the southeast of the Vietnam coast during winter and early spring in the South China Sea (SCS). The VCT is formed by the southward cold advection by the western boundary current and surface heat loss in the SCS. During the winter monsoon, the LWW first forms due to weak winds southwest of the Philippine Islands and the countering effect of warm Ekman advection against cold geostrophic advection. In spring its temperature exceeds 30 °C (LWW30), helped by strong solar radiation and the winter monsoon wake effect lee of the Philippine Islands. With the winter monsoon weakening, LWW30 extends southwestward in late spring but disappears quickly after the summer monsoon onset. Reduced latent heat flux in the winter monsoon wake is the dominant factor for the spring fast warming southwest of the Philippine Islands.Both VCT and LWW persist from winter to early spring as the Philippine Islands block the winter monsoon. Their interannual variations are correlated with the variation of the LWW30 since the blockage of the winter monsoon by the Philippine Islands modifies surface latent heat flux and ocean advection from winter to early spring. These results strongly suggest that the LWW30 is a result of land–sea–winter monsoon interaction. 相似文献
13.
CLIMATIC FEATURES OF SEA TEMPERATURE OF WARM POOL AND RELATIONSHIP WITH SST OF ITS ADJACENT REGIONS*
In this paper,climatic features of sea temperature of western Pacific warm pool and the relationship with sea surface temperature (SST) of its adjacent regions are analyzed based on the observed sea temperature on vertical cross section along 137°E in western Pacific,the monthly mean SST of Xisha Station in South China Sea and the global monthly mean SST with resolution of 1°×1° (U.K./GISST2.2).The results indicate that (1) in a sense of correlation.SST of western Pacific warm pool can represent its sea subsurface temperature from surface to 200 m-depth level in winter,and it can only represent sea temperature from surface to 70 m depth in summer.The sea subsurface temperature anomaly of warm pool may be more suitable for representing thermal regime of western Pacific warm pool.The sea subsurface temperature of warm pool has a characteristic of quasi-biennial oscillation.(2)Warm pool and Kuroshio current are subject to different ocean current systems (3)Furthermore,the relationship between SST of Xisha Station and SST of warm pool has a characteristic of negative correlation in winter and positive correlation in summer,and a better lag negative correlation of SST of Xisha Station with sea subsurface temperature of warm pool exists.(4)Additionally,oscillation structure of sea temperature like "a seesaw" exists in between warm pool and Regions Nino3 and Nino4.January (June) maximum (minimum) sea subsurface temperature anomaly of warm pool may serve as a strong signal that indicates maturity phase (development phase) of La Nina (El Nino) event,it also acts as a strong signal which reveals variations of SST of Regions Nino3 and Nino4. 相似文献
14.
前期西太平洋暖池热含量异常对中国东北地区夏季降水的影响 总被引：6，自引：0，他引：6
利用日本气象厅历史海温资料、NCEP/NCAR再分析资料、哈得来环流中心海表温度资料和降水资料,研究了1951—2010年中国东北地区夏季降水与前期西太平洋暖池(简称暖池)热含量异常的关系,并对可能影响途径进行了探讨。结果表明,中国东北地区夏季降水与前期暖池热含量有密切的负相关,前期10—11月暖池关键区(15.5°—20.5°N,125.5°—135.5°E)0—200 m热含量高(低)是预报中国东北地区夏季旱(涝)的一个很好的指标。前期暖池热含量异常激发的夏季东亚-太平洋型遥相关(EAP)和中纬度高层沿亚洲西风急流东传波列的存在,可能是影响中国东北地区夏季降水的主要原因。当前期10-11月暖池区热含量为负异常时,菲律宾反气旋异常持续存在,夏季东亚-太平洋遥相关型出现,导致西太平洋副热带高压西伸加强,中国东北地区局地异常低气压和鄂霍次克海阻塞高压形成。同时,高空存在沿西风急流传播的遥相关波列,使得中国东北地区局地异常低气压和西太平洋副热带高压在日本附近增强,有利于中国东北地区夏季降水偏多;反之亦然。 相似文献
15.
与西太平洋暖池上空对流年际变化相关联的大气环流和海温 总被引：6，自引：0，他引：6
诊断分析了热带西太平洋暖池上空对流弱和强的情况下,大气环流和海温所表现出来的差异。本文中西太平洋暖池是指（１１０－１６０°Ｅ,１０－２０°Ｎ）地区,向外射出长波辐射（ＯＬＲ）在该地区具有明显的年际变率。对西太平洋暖池对流弱和强之间大气环流和海温的差别进行了合成分析。首先,利用 ＮＣＥＰ／ ＮＣＡＰ再分析资料和卫星观测的 ＯＬＲ资料进行了分析。之后,利用欧洲中期天气预报中心再分析资料和再分析计算而得的ＯＬＲ资料重复进行了合成分析。合成结果表明由这两套资料所分析得到的结果非常相象。与西太平洋暖池上空弱（强）对流显著对应的大气环流表现为北太平洋副热带高压的西伸（东退）,以及副高西北侧更强（弱）的西风。此外,在局地（即暖池）上空,还显著对应着东（西）风异常和下沉（上升）气流异常。对应于西太平洋暖池对流强弱,最为显著的海温差别（对流弱减去对流强）为印度洋、孟加拉湾和南海的正海温异常。也就是说,西太洋暖池上空的对流与局地海温异常只有微弱的联系,而与其西部的海温异常密切相关。 相似文献
16.
Hu Shijian Hu Dunxin Guan Cong Xing Nan Li Jianping Feng Junqiao 《Climate Dynamics》2017,49(7-8):2431-2449
Climate Dynamics - Sea surface temperature (SST) structure inside the western Pacific warm pool (WPWP) is usually overlooked because of its distinct homogeneity, but in fact it possesses a clear... 相似文献
17.
利用1951-2007年华东地区14个代表站冬季(12-2月)温度资料和北半球500 hPa高度及北太平洋海温资料,通过合成分析、相关分析等方法,研究了华东地区冬季气温的气候变化及其与北半球500 hPa高度场、北太平洋海温场的关系.结果表明:华东地区冬季气温具有明显的年代际气候变化特征;前期夏季北半球500 hPa高度距平场和前期春季北太平洋海温距平场分布可作为华东冬季异常冷暖年的前兆信号;夏季北太平洋中部地区500 hPa高度场变化及前期10月西太平洋副高强弱变化,对华东地区冬季气温变化具有很好的指示性;春季南赤道海流区和西风漂流区海温异常变化,对华东地区冬季气温变化也具有很好的指示意义. 相似文献
18.
020106 西太平洋暖池区海表水温暖异常对东亚夏季风影响的研究 总被引：15，自引：2，他引：13
对夏季热带西太平洋暖池区海表水温暖异常年的东亚大气环流做了合成分析,然后用奇异值分解(SVD)方法做了进一步统计检验,揭示了东亚夏季风变异与暖池区海表水温异常的密切关系和它们间最佳耦合模态.结果发现当夏季暖池区暖异常时,在对流层低层西太平洋地区可产生一个强的反气旋偏差环流,使得副热带高压南侧东风气流大大加强,并向西伸展到中南半岛南部,从而影响了东南亚热带和副热带地区西南季风的变化(强/弱).中南半岛至中国东部大陆夏季风增强,赤道东印度洋、南海南部和中部、西太平洋热带地区夏季风减弱.SVD分析还发现经向风和纬向风与海表水温之间各存在两个最佳耦合模态,结果表明,不仅整个暖池海表水温暖/冷异常对东亚大气环流异常有重要影响,而且暖池区内海表水温有显著的暖和冷异常差异时,对东亚大气环流的影响也很明显(耦合总体平方协方差约占总体协方差的0.20),尤其是在南海至长江以南地区. 相似文献