Dynamics and Maintenance of the Intertropical Convergence Zones

热带辐合带的动力学和维持

• 批准号: 8822980
• 负责人: David Battisti
• 金额: $ 4.85万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-05-01 至 1990-09-01
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8822980&HistoricalAwards=false
• 关键词: Dynamics; Maintenance; Intertropical; Convergence; Zones

The Intertropical Convergence Zones (ITCZs) are climatological features in the earth's atmosphere that are intimately tied to both the tropical large-scale meridional (Hadley) circulation and the low-latitude surface circulation. The ITCZs drive the meridional circulation cells which transport momentum and excess heat from the tropics to midlatitudes, thereby affecting the baroclinity of the midlatitudes and hence climate. In addition, the eastern Pacific ITCZ appears to play a role in the large El Nino/Southern Oscillation climate fluctuations. Yet the dynamics and energetics of the processes maintaining the Intertropical Convergence Zones are poorly understood. This study examines the maintenance of the ITCZ phenomenon and the associated large-scale circulation, using a General Circulation Model and a simplified 3-layer model of the tropical atmosphere. The PI will explore how the surface boundary heating (sea surface temperature) and orography effect the location, strength, energetics and dynamics of the ITCZ through a carefully designed set of GCM experiments with increasingly complicated forcing. A 3-layer model of the tropical atmosphere will be constructed and employed to facilitate in the interpretation of the GCM experiments (this model will explicitly resolve the boundary layer and the free baroclinic tropical tropospheric circulations). The results will help to better define the relationship between the ITCZ and large-scale meridional and surface circulations, and hence contribute to our knowledge of the global climate.

热带辐合带（itcz）是地球大气中的气候特征，与热带大尺度经向环流（Hadley环流）和低纬度地面环流密切相关。itcz驱动经向环流细胞，将动量和多余的热量从热带输送到中纬度地区，从而影响中纬度地区的斜压性，从而影响气候。此外，东太平洋过渡带似乎在厄尔尼诺/南方涛动的大气候波动中起作用。然而，维持热带辐合带的过程的动力学和能量学却知之甚少。本研究利用一般环流模式和简化的热带大气三层模式，探讨了ITCZ现象及其相关大尺度环流的维持。该项目将通过精心设计的一套GCM实验，探索地表边界加热（海表温度）和地形如何影响ITCZ的位置、强度、能量学和动力学。为了便于对GCM实验的解释，将建立一个三层热带大气模式（该模式将明确解析边界层和自由斜压热带对流层环流）。这些结果将有助于更好地确定ITCZ与大尺度经向和地面环流之间的关系，从而有助于我们对全球气候的认识。