The Miocene epoch (23.03–5.33 Ma) was a time interval of global warmth, relative to today. Continental configurations and mountain topography transitioned towards modern conditions, and many flora and fauna evolved into the same taxa that exist today. Miocene climate was dynamic: long periods of early and late glaciation bracketed a ∼2 Myr greenhouse interval – the Miocene Climatic Optimum (MCO). Floras, faunas, ice sheets, precipitation, pCO₂, and ocean and atmospheric circulation mostly (but not ubiquitously) covaried with these large changes in climate. With higher temperatures and moderately higher pCO₂ (∼400–600 ppm), the MCO has been suggested as a particularly appropriate analogue for future climate scenarios, and for assessing the predictive accuracy of numerical climate models – the same models that are used to simulate future climate. Yet, Miocene conditions have proved difficult to reconcile with models. This implies either missing positive feedbacks in the models, a lack of knowledge of past climate forcings, or the need for re‐interpretation of proxies, which might mitigate the model‐data discrepancy. Our understanding of Miocene climatic, biogeochemical, and oceanic changes on broad spatial and temporal scales is still developing. New records documenting the physical, chemical, and biotic aspects of the Earth system are emerging, and together provide a more comprehensive understanding of this important time interval. Here we review the state‐of‐the‐art in Miocene climate, ocean circulation, biogeochemical cycling, ice sheet dynamics, and biotic adaptation research as inferred through proxy observations and modelling studies.

中文翻译：

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中新世：过去的未来

相对于今天，中新世时代（23.03–5.33 Ma）是全球温暖的时间间隔。大陆构造和山脉地貌向现代条件过渡，许多动植物演变成如今存在的同一分类单元。中新世气候是动态的：长期的早，晚冰川期约有2 Myr温室间隔–中新世气候最佳（MCO）。植物区系，动物区系，冰原，降水，p CO ₂以及海洋和大气环流大多（但并非无处不在）与气候的这些大变化相关。温度较高且p CO ₂适度较高（〜400–600 ppm），MCO被建议作为未来气候情景和评估数值气候模型（与模拟未来气候相同的模型）的预测准确性的特别合适的模拟物。然而，中新世条件已被证明很难与模型协调。这意味着要么缺少模型中的正反馈，要么缺乏对过去气候强迫的了解，要么需要重新解释代理，这可能会减轻模型数据的差异。我们对中新世气候，生物地球化学和海洋变化在广泛的时空尺度上的理解仍在发展。记录地球系统物理，化学和生物方面的新记录正在涌现，它们共同提供了对该重要时间间隔的更全面的了解。