The Walker circulation connects the regions with deep atmospheric convection in the western tropical Pacific to the shallow‐convection, tropospheric subsidence, and stratocumulus cloud decks of the eastern Pacific. The purpose of this study is to better understand the multi‐scale interactions between the Walker circulation, cloud systems, and interactive radiation. To do this we simulate a mock‐Walker Circulation with a full‐physics general circulation model using idealized boundary conditions. Our experiments use a doubly‐periodic domain with grid‐spacing of 1, 2, 25, and 100 km. We thus span the range from General Circulation Models (GCMs) to Cloud‐system Resolving Models (CRMs). Our model is derived from the Geophysical Fluid Dynamics Laboratory atmospheric GCM (AM4.0). We find substantial differences in the mock‐Walker circulation simulated by our GCM‐like and CRM‐like experiments. The CRM‐like experiments have more upper level clouds, stronger overturning circulations, and less precipitation. The GCM‐like experiments have a low‐level cloud fraction that is up to 20% larger. These differences leads to opposite atmospheric responses to changes in the longwave cloud radiative effect (LWCRE). Active LWCRE leads to increased precipitation for our GCMs, but decreased precipitation for our CRMs. The LWCRE leads to a narrower rising branch of the circulation and substantially increases the fraction of precipitation from the large‐scale cloud parameterization. This work demonstrates that a mock‐Walker circulation is a useful generalization of radiative convective equilibrium that includes a large‐scale circulation.

中文翻译：

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模拟沃克环流中的云和辐射

沃克环流将热带太平洋西部具有深层大气对流的区域连接到东太平洋的浅对流，对流层沉降和层积云层。这项研究的目的是更好地了解沃克环流，云系统和相互作用辐射之间的多尺度相互作用。为此，我们使用理想化的边界条件，通过全物理通用循环模型模拟沃克循环。我们的实验使用双周期域，网格间距为1、2、25和100 km。因此，我们涵盖了从一般流通模型（GCM）到云系统解决模型（CRM）的范围。我们的模型源自地球物理流体动力学实验室的大气GCM（AM4.0）。通过类GCM和类CRM实验，我们在模拟沃克循环中发现了实质性差异。类似于CRM的实验具有更多的高层云，更强的倾覆环流和更少的降水。类似于GCM的实验具有较低的云层分数，最高可达20％。这些差异导致对长波云辐射效应（LWCRE）的变化产生相反的大气响应。活跃的LWCRE导致GCM的降水增加，但CRM的降水减少。LWCRE导致环流上升分支变窄，并大大增加了大规模云参数化产生的降水比例。这项工作证明了沃克模拟环流是对流对流平衡的有用概括，其中包括大尺度环流。