Simulating Miocene warmth: insights from an opportunistic Multi-Model ensemble (MioMIP1)
Simulating Miocene warmth: insights from an opportunistic Multi-Model ensemble (MioMIP1)
复制标题
模拟中新世的温暖：来自机会主义多模型集合的见解 (MioMIP1)
DOI：
10.1002/essoar.10505870.1
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Burls N
中科院分区：
文献类型：
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作者：
Burls N
中新世，横跨23.03-5.33 Ma，是一个持续的、极地放大的温暖的动态气候。中新世大气二氧化碳浓度通常重建在300至600ppm之间，并在中新世气候最佳时期(16.75-14.5 Ma)可能更高。由于地表温度的重建指向了相当大的中纬度和极地温暖，目前还不清楚是什么过程维持了比现代弱得多的赤道到极地温差。在这里，我们综合了几个中新世气候模拟工作，以及可用的陆地和海洋表面温度重建。我们评估了模型数据一致性的范围，强调了在中新世建模工作和地区之间运行的稳健机制，在这些地区，不同的实验导致了变暖反应的大范围传播。规定的二氧化碳是控制全球变暖的主要因素。平均而言，除二氧化碳以外的其他因素，如中新世古地理和冰盖，使全球平均气温上升了∼2°C，在给定的二氧化碳浓度下(由于强制边界条件的扩散和气候反馈强度的综合作用)，全球变暖的扩散相当于∼的1.2倍。这项研究使用了一系列机会：模型、边界条件和参考数据集代表了中新世的最新技术，但不均匀，对于正式的模型间比较工作并不理想。认识到这一点，这项研究仍然是迄今为止尝试的第一次中新世多模型、多代理比较。这项研究旨在评估目前在模拟中新世温度方面的进展，同时隔离剩余的挑战，社区领导的努力在一个共同的分析框架内协调建模和数据活动可能会很好地解决这些挑战。
The Miocene epoch, spanning 23.03–5.33 Ma, was a dynamic climate of sustained, polar amplified warmth. Miocene atmospheric CO2concentrations are typically reconstructed between 300 and 600 ppm and were potentially higher during the Miocene Climatic Optimum (16.75–14.5 Ma). With surface temperature reconstructions pointing to substantial midlatitude and polar warmth, it is unclear what processes maintained the much weaker‐than‐modern equator‐to‐pole temperature difference. Here, we synthesize several Miocene climate modeling efforts together with available terrestrial and ocean surface temperature reconstructions. We evaluate the range of model‐data agreement, highlight robust mechanisms operating across Miocene modeling efforts and regions where differences across experiments result in a large spread in warming responses. Prescribed CO2is the primary factor controlling global warming across the ensemble. On average, elements other than CO2, such as Miocene paleogeography and ice sheets, raise global mean temperature by ∼2°C, with the spread in warming under a given CO2concentration (due to a combination of the spread in imposed boundary conditions and climate feedback strengths) equivalent to ∼1.2 times a CO2doubling. This study uses an ensemble of opportunity: models, boundary conditions, and reference data sets represent the state‐of‐art for the Miocene, but are inhomogeneous and not ideal for a formal intermodel comparison effort. Acknowledging this caveat, this study is nevertheless the first Miocene multi‐model, multi‐proxy comparison attempted so far. This study serves to take stock of the current progress toward simulating Miocene warmth while isolating remaining challenges that may be well served by community‐led efforts to coordinate modeling and data activities within a common analytical framework.