Comparison of climate and carbon cycle dynamics during late Quaternary interglacials using a spectrum of climate system models, ice-core and terrestrial archives (COIN)

第四纪间冰期在气候、植被覆盖和大气二氧化碳方面表现出不同的幅度和不同的变化模式。该项目将使用一系列地球系统模型对间冰期环境进行数值模拟的结果与新产生的植被和气候数据以及陆地和海洋档案的数据合成结合在一起。古气候数据被用来确定模式模拟能够再现间冰期气候的哪些方面，以及所测试的强迫机制(温室气体、冰盖、植被反馈、日照进动和倾斜分量)中的哪些驱动了过去温暖时段的气候变化。通过分析粗分辨率EMIC CLIMBER2-LPJ的数千年模拟，并与高分辨率模式CCSM 3的时间切片模拟进行比较，讨论了土地覆盖与气候之间反馈的重要性。该项目最后阶段的主要重点是中布朗日事件早期间冰期的数据模型比较。为此，我们将进行气候模拟的后处理，并根据贝加尔湖的长花粉记录、Suigetsu湖的花粉和硅藻记录以及综合现有的间冰期早期和晚期(100-650ka)的陆地和海洋气候记录，建立新的重建。数据与模型的比较围绕七个关键假设进行，使我们能够对第四纪间冰期进行重点定量评估，主要目的是增进我们对气候系统的了解，以便更好地约束用于未来气候预测的地球系统模型。

Quaternary interglacials show varying amplitudes and different patterns of changes in climate, vege-tation cover, and atmospheric CO2. This project combines the results of numerical simulations of interglacial environments using a spectrum of Earth-system models with newly generated vegetation and climate data and data syntheses from terrestrial and marine archives. The paleoclimate data are used to determine which aspects of the interglacial climate the model simulations are able to repro-duce and which of the tested forcing mechanisms (greenhouse gases, ice-sheets, vegetation feed-backs, precession and obliquity components of insolation) have driven climate change of past warm intervals. The importance of feedbacks between land cover and climate is being addressed by ana-lysing multi-millennial simulations of a coarse-resolution EMIC, CLIMBER2-LPJ, and compared with time-slice simulations of the high-resolution model CCSM 3. The main focus of this final phase of the project is on data-model comparison for early interglacials across the Mid-Brunhes Event. To this end we will engage in post-processing of climate simulations and establishment of new reconstructions based on long pollen records from Lake Baikal, pollen and diatom records from Lake Suigetsu and a synthesis of existing terrestrial and marine climate records of early and late interglacials (100-650 ka). The data-model comparison is structured along seven key hypotheses allowing us to carry out a focused quantitative assessment of Quaternary interglacials with the overarching aim to improve our understanding of the climate system so as to better constrain the Earth-system models used for future climate projections.