Abstract. A critical stage in the development of our ability to model and project climate change occurred in the late 1950s–early 1960s when the first primitive-equation atmospheric general circulation models (AGCMs) were created. A rather idiosyncratic project to develop an AGCM was conducted virtually alone by Cecil E. Leith starting near the end of the 1950s. The Leith atmospheric model (LAM) appears to have been the first primitive-equation AGCM with a hydrological cycle and the first with a vertical resolution extending above the tropopause. It was certainly the first AGCM with a diurnal cycle, the first with prognostic clouds, and the first to be used as the basis for computer animations of the results. The LAM project was abandoned in approximately 1965, and it left almost no trace in the journal literature. Remarkably, the recent internet posting of a half-century-old computer animation of LAM-simulated fields represents the first significant “publication” of results from this model. This paper summarizes what is known about the history of the LAM based on the limited published articles and reports as well as transcripts of interviews with Leith and others conducted in the 1990s and later.

中文翻译：

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全球气候建模的曙光：Leith大气模型的奇怪案例

摘要。1950年代末至1960年代初，当我们建立了第一个原始方程式大气总循环模型（AGCM）时，我们对气候变化进行建模和预测的能力发展的关键阶段。Cecil E. Leith大约在1950年代末开始，实际上是一个单独的开发AGCM的项目。Leith大气模型（LAM）似乎是第一个具有水文循环的原始方程式AGCM，也是第一个具有在对流层顶上方延伸的垂直分辨率的原始方程式。当然，这是第一个具有昼夜周期的AGCM，第一个具有预后云的AGCM，并且第一个被用作结果计算机动画的基础。LAM项目在1965年左右被放弃，在期刊文献中几乎没有留下任何痕迹。值得注意的是 最近在互联网上发布的关于LAM模拟字段的半个世纪历史的计算机动画代表了该模型结果的第一个重要“公布”。本文基于有限的文章和报告以及1990年代及以后进行的对Leith等人的采访记录，总结了有关LAM历史的知识。