热带西太平洋大气气候基本态与厄尔尼诺期间赤道附近西风异常
The role of atmosphere climate basic state in the formation of westerly over the equatorial Pacific
-
摘要: 利用合成分析的方法分析了自1961年以来观测到的8次厄尔尼诺事件中赤道西太平洋地区西风异常与大气气候基本态的关系,结果发现厄尔尼诺年赤道西太平洋地区西风异常具有和大气气候基本态相一致的季节变化特征.利用一个简单热带海-气耦合模式较好地模拟出了观测到的厄尔尼诺年赤道西太平洋地区西风异常的变化特征.对模式结果的分析表明,大气气候基本态对厄尔尼诺年赤道西太平洋地区西风异常的形成起重要作用,它是通过影响大气模式中的加热场来影响赤道西太平洋地区西风异常.大气模式中赤道太平洋地区的加热场的形成具有阶段性和地区性,在厄尔尼诺事件的初始阶段,大气气候基本态是大气模式中的加热场形成的主要因子,而在厄尔尼诺事件的发展和成熟阶段,赤道中东太平洋地区的海表温度异常(SSTA)是加热场形成的主要因子.模式模拟结果对大气气候基本态依赖的敏感性试验说明,在大气模式加热场中含有大气气候基本态的模拟中,沿中西太平洋赤道附近的纬向风异常表现出和观测类似的传播特征.Abstract: The relationship between atmosphere climate basic state and westerly wind anomalies over the equatorial western Pacific is studied by using composite method during 8 El Niño year since 1961.It is found that the western wind anomaly over equatorial western Pacific shows clear seasonal variability similar to that in the atmosphere climate basic state.These characteristics of seasonal variation are successfully simulated with a simple equatorial ocean-atmosphere coupled model.The model results show that the atmosphere basic climate state is very important for generation of western wind anomaly over the equatorial western Pacific.Atmosphere basic climate state effects on the western wind anomaly over the equatorial western Pacific through the heating in the atmosphere model.The effects of SSTA and atmosphere climate basic state on the heating in the atmosphere model vary with the phase of ENSO cycle and geographical location.In the beginning of EN50 cycle,the atmosphere climate basic state plays an important role in forming heating field in the atmosphere model over the equatorial Pacific.During the developing or mature phase of ENSO cycle,the SSTA plays a more important role in forming heating field in the atmosphere model over the mid-eastern equatorial Pacific.Sensitive test of the coupled model to atmosphere climate basic state was made.It shows that the propagating characteristics of westerly wind anomaly along the equatorial Pacific close to the observations.
-
Key words:
- El Niñ /
- o events /
- ocean-atmosphere coupled model
-
WYRTKI K.El Niño:The dynamics response of the equatorial Pacific to atmospheric forcing[J].J Phys Oceanogr,1975,5:572~584. BUSALACCHI A J,Q'BRIEN J J.Interannual variability of the equatorial Pacific in the 1960s[J].J Geophys Res,1981,86:10 901~10 907. BUSALACCHI A J,TAKEUCHI K,Q'BRIEN J J.Interannual variability of the equatorial Pacific-revisited[J].J Geophys Res,1983,88:7 551~7 562. HUANG Rong-hui,ZANG Xiao-yun,ZHANG Ren-he,et al.The westerly anomalies over the tropical Pacific and their dynamical effect on the ENSO cycles during 1980~1994[J].Advance in Atmospheric Sciences,1998,15:135~151. 张人禾,黄荣辉.E1 Niño事件发生和消亡中热带太平洋纬向风应力的动力作用I.资料诊断和理论分析[J] 大气科学,1998,22:587~599 黄荣辉,付云飞.关于ENSO循环动力学研究的若干进展与问题[A] 黄荣辉等灾害性气候预测及其农业年景和水资源调配的影响项目论文集Ⅱ灾害性气候的过程及诊断[C] 北京:气象出版社,1996 172~188 付云飞,黄荣辉热带太平洋西风异常对ENSO事件发生的作用[J] 大气科学,1996,20:641~653 付云飞,黄荣辉.东亚西风异常活动对热带西太平洋西风爆发及ENSO发生的作用[J].大气科学,1997,2l:485~492 严邦良,黄荣辉,张人禾.H Niño事件发生和消亡中热带太平纬向风应力的动力作用Ⅱ模式结果[J] 大气科学,2001.25:160~172. LAU K M.Intraseasonal and interannual variations of tropical convection:A possible link between the 40~50 day oscillation and ENSO ? [J].J Atmos Sci,1988,45:506~519. NITTA Ts,MOTOKI T.Abrupt enhancement of convective activity and low-level westerly burst during the onset phase of the 1986-87 El Niño[J].J Meteor SOc Japan,1987,65:497~506. BARNETT,T P.Interaction of the monsoon and the Pacific trade wind system in interannual time seals.Part I.The equatorial zone[J].Mon Wea Rev,1983,111:756~773. RASMUSSON F M,CARPENDER T H.Varations in tropical sea surface temperature and surface wind fields associated with the Southern Oscillation El Niño[J].Mon Wea Rev,1982,110:354~384. JUJ,SLINGOJ.The Asian summer monsoon andENSO[J].Quart J RoyMeter SOc,1995,121:1 133~1 168. WEBSTER P J,YANG S.Monsoon and ENSO:electively interaction system[J].Quart J Roy Meteorol Soc,1992,118:877~925. WEBSTER,P J.The annual cycle and the predictability of the tropical coupled ocean-atmosphere system[J].Meteor and Atmos Phys,1995,56:33~55. PHILANDER S G.El Niño-Southern Oscillation phenomena[J].Nature,1983,302:295~301. ZEBIAK S E,CANE M A.A model El Niño/Southern Oscillation[J].Mon Wea Rev,1987,115:2 262~2 278. KLEEMAN R.A simple model of the atmospheric response to ENSO SST anomalies[J].J Atmos SCi,1991,48:3~18. 严邦良,黄荣辉,张人禾.一个可以模拟ENSO循环基本特点的简单海气耦合模式[J] 大气科学,2002,26(2) GILL A E.Some simple solusions for heat induced tropical circulation[J].Quart J Roy Meteor Soc,1980,106:447~462. WANG C,WEISBERG R H,VIRMANI J I.Western Pacific interannual variability associated with the El Niño-southernOscillation[J].J Geophys Res,1999,104:5 131~5 149.
点击查看大图
计量
- 文章访问数: 824
- HTML全文浏览量: 41
- PDF下载量: 1016
- 被引次数: 0