Tropical Wave Driving of the Annual Cycle in Tropical Tropopause Temperatures. Part II: Model Results
Tropical Wave Driving of the Annual Cycle in Tropical Tropopause Temperatures. Part II: Model Results
复制标题
热带对流层顶温度年周期的热带波驱动。
DOI：
10.1175/jas3698.1
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发表时间：
2006
影响因子：
3.1
通讯作者：
W. Norton
中科院分区：
文献类型：
--
作者：
W. Norton
本文用定常波的激发和定常波对热带对流层顶附近平均气流的影响来研究大气对热带加热的局部分布的响应。这是通过检查非线性模拟的吉尔模型与原始方程模型，从表面延伸到平流层。当赤道加热时，模式在热带对流层顶附近产生较强的纬向平均温度冷却，而当15°N加热时，模式产生较弱的冷却。该模型表明，赤道Rossby波，穿透平流层下部和EP通量散度的变化，对应于12月和8月之间的观测变化。有人建议，在热带对流层上部的上升是由涡度平流或等效的位涡通量，由于这些赤道Rossby波，特别是当加热是接近赤道。模型结果支持了年周期在时间上变化的假设。
Abstract The atmospheric response to a localized distribution of tropical heating is examined in terms of the stationary waves excited and how these impact the mean flow near the tropical tropopause. This is done by examining nonlinear simulations of the Gill model with a primitive equation model that extends from the surface up into the stratosphere. The model produces strong cooling of zonal mean temperatures near the tropical tropopause when the heating is on the equator but weaker cooling with the heating at 15°N. The model shows that equatorial Rossby waves that penetrate the lower stratosphere and changes in EP flux divergence that correspond to the observed changes between December and August. It is suggested that ascent in the upper tropical troposphere is driven by vorticity advection or equivalently potential vorticity fluxes due to these equatorial Rossby waves, particularly when the heating is close to the equator. The model results provide support to the hypothesis that the annual cycle in tr...