Abstract The evolution of the Northern Hemisphere oceanic gateways has facilitated ocean circulation changes and may have influenced climatic variations in the Cenozoic time (66 Ma–0 Ma). However, the timing of these oceanic gateway events is poorly constrained and is often neglected in global paleobathymetric reconstructions. We have therefore re-evaluated the evolution of the Northern hemisphere oceanic gateways (i.e. the Fram Strait, Greenland–Scotland Ridge, the Central American Seaway, and the Tethys Seaway) and embedded their tectonic histories in a new global paleobathymetry and topography model for the Cenozoic time. Our new paleobathymetry model incorporates Northeast Atlantic paleobathymetric variations due to Iceland mantle plume activity, updated regional plate kinematics, and models for the oceanic lithospheric age, sediment thickness, and reconstructed oceanic plateaus and microcontinents. We also provide a global paleotopography model based on new and previously published regional models. In particular, the new model documents important bathymetric changes in the Northeast Atlantic and in the Tethys Seaway at Eocene–Oligocene transition (~34 Ma), the time of the first glaciations of Antarctica, believed to be triggered by the opening of the Southern Ocean gateways (i.e. the Drake Passage and the Tasman Gateway) and subsequent Antarctic Circumpolar Current initiation. Our new model can be used to test whether the Northern Hemisphere gateways could have also played an important role modulating ocean circulation and climate at that time. In addition, we provide a set of realistic global bathymetric and topographic reconstructions for the Cenozoic time at one million-year interval for further use in paleo-ocean circulation and climate models.

中文翻译：

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全球新生代古水深测量，重点是北半球海洋门户

摘要 北半球海洋门户的演化促进了海洋环流的变化，并可能影响了新生代（66 Ma-0 Ma）的气候变化。然而，这些海洋门户事件的时间限制很差，在全球古水深测量重建中经常被忽略。因此，我们重新评估了北半球海洋门户（即弗拉姆海峡、格陵兰-苏格兰海岭、中美洲航道和特提斯海道）的演化，并将它们的构造历史嵌入到新的全球古深海测量和地形模型中新生代时期。我们新的古水深测量模型结合了由于冰岛地幔柱活动、更新的区域板块运动学以及海洋岩石圈年龄、沉积物厚度、以及重建的海洋高原和微大陆。我们还提供了一个基于新的和以前发布的区域模型的全球古地形模型。特别是，新模型记录了始新世-渐新世过渡时期（~34 Ma）东北大西洋和特提斯海道的重要水深变化，南极洲第一次冰川作用的时间，据信是由南大洋的开放引发的门户（即德雷克海峡和塔斯曼门户）和随后的南极环极流启动。我们的新模型可用于测试当时北半球门户是否也可以在调节海洋环流和气候方面发挥重要作用。此外，