Convectively Coupled Equatorial Waves. Part III: Synthesis Structures and Their Forcing and Evolution
Convectively Coupled Equatorial Waves. Part III: Synthesis Structures and Their Forcing and Evolution
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对流耦合赤道波。
DOI：
10.1175/jas4019.1
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发表时间：
2007
影响因子：
3.1
通讯作者：
Yang G
中科院分区：
文献类型：
--
作者：
Yang G
本研究的第一部分和第二部分的基础上，向东和向西移动的对流耦合赤道波的结构进行检查，通过合成标准的赤道波水平结构的投影。这些赤道波分量之间的相互作用和它们的演变进行了研究。结果表明，总的东移场及其与赤道对流的耦合与对流层低层的标准Kelvin波非常相似，东半球对流增强与异常西风同相，西半球对流增强与异常辐合同相。而在对流层上层，总场表现为Kelvin波和更高（n= 0和1）波结构的混合，并伴有强纬向风和辐散。赤道总场显示了EH中的修改后的第一内部Kelvin波垂直结构，在垂直方向上有倾斜，在对流层中部有第三个峰值。有证据表明，EH对流层中层Kelvin波密切相关的SH外向东移动的波活动，垂直速度与波活动延伸到赤道地区的对流层中上部。在赤道过渡季和盛夏过渡季，对流层中层纬向风场和位势高度场呈现出与强迫波有关的变化，而与离赤道对流有关的西向流场则表现出截然不同的特征。在EH盛夏，总场具有斜压结构，与赤道外对流与相对温暖的空气，表明对流强迫的动力场。总的结构表现出的混合物，然后= 0，1分量，前者占主导地位的对流东部和后者的对流西部。然后= 0分量被发现是密切相关的低层n = 1 Rossby（R1）波，出现较早，似乎提供组织的对流，这反过来又迫使然后= 0波。在WH转换季节，总场具有正压结构，并以R1波为主。有证据表明，这正压R1波，以及相关的热带对流，是被迫由北半球对流层上层的外对流Rossby波活动。在EH中，与赤道对流相关的向西移动的低层风结构类似于R1波，赤道西风带与增强的对流同相。然而，向西移动的n =-1和n = 0的结构也参与其中。
Building on Parts I and II of this study, the structures of eastward- and westward-moving convectively coupled equatorial waves are examined through synthesis of projections onto standard equatorial wave horizontal structures. The interaction between these equatorial wave components and their evolution are investigated. It is shown that the total eastward-moving fields and their coupling with equatorial convection closely resemble the standard Kelvin wave in the lower troposphere, with intensified convection in phase with anomalous westerlies in the Eastern Hemisphere (EH) and with anomalous convergence in the Western Hemisphere (WH). However, in the upper troposphere, the total fields show a mixture of the Kelvin wave and higher (n= 0 and 1) wave structures, with strong meridional wind and its divergence. The equatorial total fields show what may be described as a modified first internal Kelvin wave vertical structure in the EH, with a tilt in the vertical and a third peak in the midtroposphere. There is evidence that the EH midtropospheric Kelvin wave is closely associated with SH extratropical eastward-moving wave activity, the vertical velocity associated with the wave activity stretching into the equatorial region in the mid–upper troposphere. The midtropospheric zonal wind and geopotential height show a pattern that may be associated with a forced wave.The westward-moving fields associated with off-equatorial convection show very different behaviors between the EH midsummer and the WH transition seasons. In the EH midsummer, the total fields have a baroclinic structure, with the off-equatorial convection in phase with relatively warm air, suggesting convective forcing of the dynamical fields. The total structures exhibit a mixture of then= 0, 1 components, with the former dominating to the east of convection and the latter to the west of convection. Then= 0 component is found to be closely connected to the lower-leveln= 1 Rossby (R1) wave that appears earlier and seems to provide organization for the convection, which in turn forces then= 0 wave. In the WH transition season the total fields have a barotropic structure and are dominated by the R1 wave. There is evidence that this barotropic R1 wave, as well as the associated tropical convection, is forced by the NH upper-tropospheric extratropical Rossby wave activity. In the EH, westward-moving lower-level wind structures associated with equatorial convection resemble the R1 wave, with equatorial westerlies in phase with the intensified convection. However, westward-movingn= −1 andn= 0 structures are also involved.
影响因子：
3.1
作者：
Yang G
通讯作者：
Yang G
新哈德利中心全球环境模型 (HadGEM1) 中大气的物理特性。
DOI：
--
发表时间：
2006
期刊：
影响因子：
--
作者：
M. Ringer;G. Martin;C. Z. Greeves;T. Hinton;P. James;V. Pope;Adam A. Scaife;R. Stratton;P. Inness;J. Slingo;Gui‐Ying Yang
通讯作者：
Gui‐Ying Yang