In this two‐part paper, a description is provided of a version of the AM4.0/LM4.0 atmosphere/land model that will serve as a base for a new set of climate and Earth system models (CM4 and ESM4) under development at NOAA's Geophysical Fluid Dynamics Laboratory (GFDL). This version, with roughly 100 km horizontal resolution and 33 levels in the vertical, contains an aerosol model that generates aerosol fields from emissions and a “light” chemistry mechanism designed to support the aerosol model but with prescribed ozone. In Part 1, the quality of the simulation in AMIP (Atmospheric Model Intercomparison Project) mode—with prescribed sea surface temperatures (SSTs) and sea‐ice distribution—is described and compared with previous GFDL models and with the CMIP5 archive of AMIP simulations. The model's Cess sensitivity (response in the top‐of‐atmosphere radiative flux to uniform warming of SSTs) and effective radiative forcing are also presented. In Part 2, the model formulation is described more fully and key sensitivities to aspects of the model formulation are discussed, along with the approach to model tuning.

中文翻译：

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GFDL全球大气和陆地模型AM4.0 / LM4.0：1.具有规定的SST的模拟特性

在此分为两部分的论文中，提供了对AM4.0 / LM4.0大气/土地模型的版本的描述，该模型将作为正在开发的一组新的气候和地球系统模型（CM4和ESM4）的基础在NOAA的地球物理流体动力学实验室（GFDL）中。该版本具有约100 km的水平分辨率和垂直的33个水平，包含一个通过排放产生气溶胶场的气溶胶模型，以及旨在支持气溶胶模型但带有规定臭氧的“轻型”化学机制。在第1部分中，描述了AMIP（大气模型比较项目）模式下的模拟质量（具有规定的海面温度（SST）和海冰分布），并将其与以前的GFDL模型以及AMIP模拟的CMIP5存档进行了比较。该模型' 还介绍了Cess敏感性（大气顶辐射通量对SST均匀变暖的响应）和有效的辐射强迫。在第2部分中，将更全面地描述模型公式，并讨论对模型公式各方面的关键敏感性以及模型调整的方法。