Anthropogenic forcing of the atmosphere by greenhouse gases (GHG) and ozone-depleting substances has provided an unintended test of the robustness of current understanding of the physics and chemistry of the middle atmosphere, that is, the stratosphere and mesosphere. We explore this topic by examining how well anthropogenic changes can be simulated by modern, comprehensive numerical models. Specifically, we discuss the simulations of trends in global mean temperature; the development of the ozone hole and its impact on the dynamics of the Southern Hemisphere, both in the stratosphere and troposphere; trends in the stratospheric Brewer–Dobson circulation; and the response of the quasi-biennial oscillation (QBO) to increasing burdens of CO₂. We find that, in most of these cases, numerical simulation is able to reproduce observed changes and provide physical insights into the relevant mechanisms. Simulation of the QBO is on a less firm footing. Although many numerical models can now generate realistic QBOs, future projections of its behavior under the increasing burdens of GHG are inconsistent and even contradictory.

中文翻译：

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中层大气对人为强迫的响应

温室气体 (GHG) 和消耗臭氧层物质对大气造成的人为强迫为当前对中层大气（即平流层和中间层）的物理和化学理解的稳健性提供了一个意想不到的测试。我们通过检查现代综合数值模型模拟人为变化的程度来探索这个主题。具体来说，我们讨论了全球平均温度趋势的模拟；臭氧空洞的发展及其对南半球平流层和对流层动力学的影响；平流层布鲁尔-多布森环流的趋势；以及准两年振荡 (QBO) 对增加的 CO ₂负担的响应. 我们发现，在大多数情况下，数值模拟能够重现观察到的变化并提供对相关机制的物理见解。QBO 的模拟基础不太稳固。尽管许多数值模型现在可以生成现实的 QBO，但在温室气体负担日益增加的情况下，其行为的未来预测是不一致的，甚至是相互矛盾的。