Climate model simulations of the PETM (Paleocene-Eocene Thermal Maximum) warming have mainly focused on replicating the global thermal response through greenhouse forcing, i.e. CO₂, at levels compatible with observations. Comparatively less effort has gone into assessing the skill of models to replicate the response of the hydrologic cycle to the warming, particularly on regional scales. Here we have assembled proxy records of regional precipitation, focusing on the Mid-Atlantic Coasts of North America (New Jersey) and Europe (Spain) to test the response of the hydrologic system to greenhouse gas forcing of the magnitude estimated for the PETM (i.e., 2×). Given evidence that the PETM initiated during a maximum in eccentricity, this includes the response under neutral and extreme orbital configurations. Modeled results show excellent agreement with observations in Northern Spain, with a significant increase in both mean annual and extreme precipitation resulting from increased CO₂ levels under a neutral orbit. The Mid Atlantic Coast simulations agree with observations showing increases in both overall and extreme precipitation as a result of CO₂ increases. In particular, the development of sustained atmospheric rivers might be significantly contributing to the extremes of the eastern Atlantic, whereas extratropical cyclones are likely contributing to the extremes in the western Atlantic. With an eccentric orbit that maximizes insolation during boreal summer, there is a suppression of extreme precipitation events in the eastern Atlantic and an amplification in the western Atlantic, which may account for observations in the relative timing of the sedimentary response to the carbon isotope excursion associated with the PETM.

PETM（古新世-始新世热最大值）变暖的气候模型模拟主要集中在通过温室强迫（即CO _2）复制全球热响应上。，其水平与观察值兼容。评估模型技巧以复制水文循环对变暖的响应的工作相对较少，特别是在区域范围内。在这里，我们收集了区域降水的代理记录，重点放在北美洲（新泽西州）和欧洲（西班牙）的中大西洋海岸，以测试水文系统对温室气体强迫的反应，其幅度为PETM估计的幅度（即，2×）。如果有证据表明PETM是在最大的离心率下启动的，则包括中性和极端轨道配置下的响应。模拟结果表明，与西班牙北部的观测结果非常吻合，由于CO ₂增加，平均年降水量和极端降水量均显着增加在中性轨道下的水平。中大西洋海岸的模拟结果与观测结果一致，这些观测结果表明，由于CO _2的增加，总体降水和极端降水均增加。特别是，持续的大气河的发展可能对东大西洋的极端事件有重大贡献，而温带气旋可能对西大西洋的极端事件有贡献。偏心轨道在北方夏季使日照最大化，因此抑制了东大西洋的极端降水事件，并抑制了西大西洋的降水，这可能解释了沉积对碳同位素偏移相关反应的相对时间的观测结果。与PETM。