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Variation of Air-Sea Heat Fluxes over the Western Pacific Warm Pool Area and Its Relationship with the South China Sea Summer Monsoon Onset
ZUO Tao,CHEN Jin-Nian,WANG Hong-Na,
ZUO Tao
,CHEN Jin-Nian,WANG Hong-Na

大气和海洋科学快报 , 2012,
Abstract: Using ECWMF ERA-40 and Interim reanalysis data, the planetary wave fluxes associated with the February extreme stratospheric polar vortex were studied. Using the three-dimensional Eliassen-Palm (EP) flux as a measure of the wave activity propagation, the authors show that the unusual warm years in the Arctic feature an anomalous weak stratosphere-troposphere coupling and weak downward wave flux at the lower stratosphere, especially over the North America and North Atlantic (NANA) region. The extremely cold years are characterized by strong stratosphere-troposphere coupling and strong downward wave flux in this region. The refractive index is used to examine the conception of planetary wave reflection, which shows a large refractive index (low reflection) for the extremely warm years and a small refractive index (high reflection) for the extremely cold years. This study reveals the importance of the downward planetary wave propagation from the stratosphere to the troposphere for explaining the unusual state of the stratospheric polar vortex in February.
The 1997–1998 warm event in the South China Sea
Dongxiao Wang,Qiang Xie,Yan Du,Weiqiang Wang,Ju Chen
Chinese Science Bulletin , 2002, DOI: 10.1007/BF02907614
Abstract: A strong warm event happens during spring 1997 to spring 1999 in the South China Sea. Its intensity and duration show that it is the strongest event on the record over the past decades. It also corresponds with the severe flood over the valley of the Yangtze River and a couple of marine environmental events. This note addressed the evolution process by using several data sets, such as sea surface temperature, height and wind stress in addition to subsurface temperature. The onset of the warm event almost teleconnects with the El Ni o event in the tropical Pacific Ocean. Summer monsoon is stronger and winter monsoon is weaker in 1997 so that there are persistent westerly anomalies in the South China Sea. During the development phase, the warm advection caused by southerly anomalies is the major factor while the adjustment of the thermocline is not obvious. Subsequently, the southerly anomalies decay and even northerly anomalies appear in the summer of 1998 resulting from the weaker than normal summer monsoon in 1998 in the South China Sea. The thermocline develops deeper than normal, which causes the downwelling pattern and the start of the maintaining phase of the warm event. Temperature anomalies in the southern South China Sea begin to decay in the winter of 1998–1999 and this warm event ends in the May of 1999.
Precursory SST anomalies associated with the convection over the western Pacific warm pool
Riyu Lu
Chinese Science Bulletin , 2002, DOI: 10.1360/02tb9158
Abstract: The convection over the tropical western Pacific warm pool influences significantly the atmospheric circulation and climate in East Asia. Thus, the precursory signals of the convection may be used in the forecast of summer climate in China. According to the present results, the June-July-August (JJA) mean convection intensity over the warm pool is significantly related to the precursory positive and negative sea surface temperatures (SSTs) in the warm pool and in the equatorial central and eastern Pacific, respectively. It is also related to the simultaneous negative surface temperatures west to the Philippines. The analysis on the SSTs associated with the convection over the warm pool in individual month of summer shows that for the convection in June and July, there are precursory SST signals in the warm pool and the equatorial central and eastern Pacific. Therefore, this study shows that only the convection in June and July, rather than that in August, has precursory SST signals, despite the existence of the precursory signals of the JJA mean convection. Accordingly, it is implied that the interaction among the warm pool, equatorial central and eastern Pacific, and the region west to the Philippines may exhibit distinct features in the precursory period (preceding winter and spring) and in the simultaneous period.
30-60-day Oscillations of Convection and Circulation Associated with the Thermal State of the Western Pacific Warm Pool during Boreal Summer
REN Baohua,HUANG Ronghui,
REN Baohu
,HUANG Ronghui

大气科学进展 , 2003,
Abstract: This study focuses on the characteristics of the 30 60-day oscillation (MJO) associated with theinterannual variability of the thermal state in the western Pacific warm pool. The composite resultsshow that the amplitude of MJO convection over the tropical western Pacific tends to intensify (reduce)in the WARM (COLD) case. The negative correlations between MJO convection in the WARM and inthe COLD cases are examined to be significant over most of the Asian-Pacific region. The evolutions of MJO convection and lower circulation, on the one hand, exhibit larger differences between the WARMand COLD cases, but on the other hand, display a unique feature in that a well-developed MJO cyclone(anticyclone) is anchored over the Asian-Western Pacific domain at the peak enhanced (suppressed) MJO convection phase over the western Pacific warm pool, either in the WARM or in the COLD case. Thisunique feature of MJO shows a Gill-type response of lower circulation to the convection and is inferred tobe an inherent appearance of MJO. The context in the paper suggests there may exist interactions between MJO and the interannual variability of the thermal state in the western Pacific warm pool.
Effects on Asian Monsoon of Gigantic Qinghai-Xizang Plateau and Western Pacific Warm Pool
Effects on Asian Monsoon of Gigantic Qinghai-Xizang Plateau and Western Pacific Warm Pool

Zhu Qiangen,Hu Jianglin,
Zhu Qiangen
,Hu Jianglin

大气科学进展 , 1995,
Abstract: A GCM study is performed of the effects on Asian summer monsoon initiation of the Qinghai-Xizang Plateau and western Pacific warm pool, results show that the Plateau, being a prominent sensible heat source, acts as a basic factor for the formation of the monsoon circulation; the northward transported low-latitude and low-level warm, moist flow in relation to the sensible heating experiences dynamic lifting on the south and east sides of the highland, releasing vast quantifies of latent heat through condensation, whereby the monsoon circulation pattern is further modulated; the temperature contrast between the Pacific warm pool and the Australian / marine continents serves as another basic factor for the northern SW summer monsoon genesis over the South-China Sea- the western Pacific, which, however, falls into a category of winter monsoon on a physical basis.
Impacts of the Thermal State and the Convective Activities in the Tropical Western Warm Pool on the Summer Climate Anomalies in East Asia
热带西太平洋暖池的热状态及其上空的对流活动对东亚夏季气候异常的影响

Huang Ronghui,Sun Fengying,
黄荣辉
,孙凤英

大气科学 , 1994,
Abstract: In this paper, impacts of the thermal state in the western tropical Pacific warm pool and the convective activities over the warm pool on the summer climate anonialies in East Asia ate analysed by using the observed data of the sea temperatare in surface and subsurface of the westem tropical Pacific warm pool, the high cloud amount and precipitation for 1978-1989. The analysed results show that the thermal state in the tropical western Pacific warm pool and the convective activities over the warm pool play an important role in the summer climate anomalies in East Asia. When the western tropical Pacific warm pool is warming, the convective activities are intensified from the area around the Philippines to the Indo-China Peninsula through the South China Sea, the western Pacific subtropical high may shift nortbward, the summer rainfall may be below normal in the Yangtze River valley and the Huaihe River valley. On the Contrary, the convective activities are weak around the Philippines, the western Pacific subtropical high may shift southward, the summer rainfall may be above normal and it may be below normal in the Yellow River valley, drought summer is frequently caused there.The observational facts also show that after the enhancement of the convective activities over the western tropical Pacific warm pool, there is a teleconnection pattern in the circu1ation anomalies over the regions from Southeast Asia to the western Coast of North America through East Asia, i.e., the so-called East Asia / Pacific Pattern.
The barrier layer in the southern region of the South China Sea
Wei Wu,M. Tomczak,Xinhua Fang,Dexing Wu
Chinese Science Bulletin , 2001, DOI: 10.1007/BF03183396
Abstract: By analysing the CTD data in the southern region of the South China Sea gathered during six cruises between 1989 and 1999, a barrier layer with seasonal variation just like what exists in the equatorial oceans is found in this region. It is the first discovery in such a marginal sea yet. It is strong in autumn and a little weak in summer and winter. The thicker the barrier layer, the higher the average temperature of the upper mixed layer. The region with the thicker barrier layer overlaps the region with the higher average temperature of the upper mixed layer, and accords with the thicker region of the warm pool in the South China Sea got from the Levitus data. The barrier layer in the southern region of the South China Sea has significant influence on the heat storage of the upper ocean there.
Coupled Modes of Rainfall over China and the Pacific Sea Surface Temperature in Boreal Summertime

LI Chun,MA Hao,

大气科学进展 , 2011,
Abstract: In this study, monthly NCEP/NCAR reanalysis data and NOAA ERSST as well as observed precipitation data from 160 stations in China were used to investigate coupled modes affecting the rainfall over China and sea surface temperature (SST) in the Pacific during boreal summertime based on singular value decomposition (SVD) method. The SVD analysis revealed three remarkable coupled modes: rainfall over North China associated with an ENSO-like SST pattern (ENSO--NC), rainfall over the Yangtze River valley associated with SST anomalies in the western tropical Pacific (WTP--YRV), and rainfall over the Yellow River loop valley associated with tropical Pacific meridional mode-like SST pattern (TPMM--YRLV). These coupled SVD modes appear robust and closely correlated with the single field. Furthermore, the covariabilities among of the three coupled modes have different characteristics at the decadal time scale. In addition, the possible atmospheric teleconnections of the coupled rainfall and SST modes were discussed. For the ENSO--NC mode, anomalous low-pressure and high-pressure over the Asian continent induces moisture divergence over North China and reduces summer rainfall there. For the WTP--YRV mode, East Asia--Pacific teleconnection induces moisture convergence over the Yangtze River valley and enhances the summer rainfall there. The TPMM SST and the summer rainfall anomalies over the YRVL are linked by a circumglobal, wave-train-like, atmospheric teleconnection.
Atmospheric Circulations and Sea Surface Temperatures Related to the Convection over the Western Pacific Warm Pool on the Interannual Scale
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

Lu Riyu,
Lu
,Riyu

大气科学进展 , 2001,
Abstract: The difference is examined in atmospheric circulation and Sea Surface Temperatures (SSTs) in the tropics and subtropics between weak and strong convection over the tropical western Pacific warm pool (signified as WPWP). The WPWP is chosen as the region (110-160°E, 10-20°N), where the Outgoing Longwave Radiation (OLR) shows a great year-to-year variance. A composite study was carried out to examine the differences in atmospheric circulation and SSTs between weak and strong convection over WPWP. First,NCEP/NCAR re-analysis data and satellite-observed OLR data are used to examine the differences.ERA data, in which the OLR data are calculated, are then used for re-examination. The composite results show that the differences are remarkably similar in these two sets of data. The difference in circulations between weak and strong convection over WPWP is significantly associated with westward extension of the North Pacific subtropical anticyclone and stronger westerlies at the northwestern edge of the subtropical anticyclone. It also corresponds with the significant easterly anomaly and the descent anomaly in situ, i.e., over the WPWP. The most prominent characteristics of the difference of SSTs between weak and strong convection over the WPWP are the significant positive SST anomalies in the Indian Ocean,the Bay of Bengal and the South China Sea. In WPWP, however, there are only weak negative SST anomalies. Thus, the anomaly of OLR over WPWP is weakly associated with the SST anomalies in situ, while closely associated with the SST anomalies west of WPWP.
Trends of sea level rise in the South China Sea during the 1990s: An altimetry result

LI Li,XU Jindian,CAI Rongshuo,

科学通报(英文版) , 2002,
Abstract: Using 7 years of TOPEX/POSEIDON satellite altimetry data, we have identified a general trend of sea level rising in the South China Sea between January 1993 and December 1999. The estimated bulk rising rate of the entire basin is ~1 cm/a. The rise of sea level appears to be spatially non-homogeneous, which shows a highest rate of 2.7 cm/a in the deep basin west of Luzon and generally Iow (even negafive) rates over the shallow continental shelves. It is believed that the observed rapid rising of sea level is a regional phenomenon and is mainly caused by warming of the upper layer of the South China Sea, which showed a bulk warming rate of 0.15℃/a in the same period. It is also suggested that the observed rising trend is mainly a decadal signal, which is possibly associated with decadal variation of the Pacific warm pool region.
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