The interactions between tropical convection and atmospheric waves are investigated in an idealized, i.e., two-dimensional (2D) and non-rotating, framework. The dissertation is made up of three parts. The first investigates the linear response of an initially motionless tropical atmosphere to a spatially and temporally localized deep convective heat source. Consistent with output from high-resolution numerical simulations, results show that the heat source tends to strongly excite gravity wave packets with phase speeds in the range 35–45 m s−1 and 16–20 m s−1 , and that the passage of the faster- (slower-) moving packets should tend to inhibit (favor) the development of additional deep convection.; Part II discusses a linear tropical wave model in which vertical structure is truncated to include just two vertical normal modes: a fast-moving (first internal) mode and a slow-moving (second internal) mode. Based on the notion that deep convective development is strongly inhibited by the effects of dry air entrainment, anomalies in deep convective heating are assumed to be directly proportional to anomalies in column-integrated moisture. The model predicts that large-scale convectively coupled gravity waves, with realistic phase speeds and vertical temperature structures, should spontaneously develop from random initial conditions, even in the absence of a mean flow. Stratiform and deep convective heating processes both play an important role in the instability.; In Part III, a vertical normal mode transform algorithm is used to analyze the structure and energetics of large-scale [O(1000 km)] convectively coupled gravity waves that spontaneously develop in a 2D cloud resolving model simulation of radiative convective equilibrium. Results show that the simulated waves primarily owe their existence to an unstable interaction between convection and modes with phase speeds in the range 16–18 m s−1 (i.e., third internal modes). Stratiform heating processes are found to play an important role in maintaining the energy of these modes, in agreement with stratiform instability theory. In contrast to this theory, however, deep convective heating processes also play an important role.
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机译：在理想的二维（2D）非旋转框架下研究了热带对流与大气波之间的相互作用。论文由三部分组成。第一个研究了最初静止不动的热带大气对时空局部深对流热源的线性响应。与高分辨率数值模拟的输出一致，结果表明，热源倾向于以相速度在35–45 ms -1 和16–20 ms 范围内的重力波强烈激发。 −1 ，并且运动较快（较慢）的小包的通过应倾向于抑制（有利）其他深对流的发展。第二部分讨论线性热带波浪模型，其中垂直结构被截断为仅包括两个垂直法线模式：快速移动（第一内部）模式和慢速移动（第二内部）模式。基于干燥空气夹带的作用强烈抑制深对流发展的观点，假定深对流加热的异常与柱积分水分的异常成正比。该模型预测，具有现实相速度和垂直温度结构的大规模对流耦合重力波，即使在没有平均流量的情况下，也应从随机的初始条件自发发展。层状和深层对流加热过程均对不稳定性起重要作用。在第三部分中，使用垂直法向模变换算法分析在辐射对流平衡的二维云解析模型模拟中自发形成的大尺度[O（1000 km）]对流耦合重力波的结构和能量。结果表明，模拟波的存在主要是由于对流与模式速度在16–18 m s -1 范围内的模式（即第三内部模式）之间的不稳定相互作用所致。与层状不稳定性理论相一致，发现层状加热过程在维持这些模式的能量方面起着重要作用。但是，与该理论相反，深对流加热过程也起着重要作用。
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