Transient simulations for present and last interglacials using a comprehensive coupled climate model CCSM3 (Community Climate System Model 3.0), links to model result files in NetCDF format

Transient simulations are widely used in studying the past climate as they provide better comparison with any exisiting proxy data. However, multi-millennial transient simulations using coupled climate models are usually computationally very expensive. As a result several acceleration techniques are implemented when using numerical simulations to recreate past climate. In this study, we compare the results from transient simulations of the present and the last interglacial with and without acceleration of the orbital forcing, using the comprehensive coupled climate model CCSM3 (Community Climate System Model 3). Our study shows that in low-latitude regions, the simulation of long-term variations in interglacial surface climate is not significantly affected by the use of the acceleration technique (with an acceleration factor of 10) and hence, large-scale model-data comparison of surface variables is not hampered. However, in high-latitude regions where the surface climate has a direct connection to the deep ocean, e.g. in the Southern Ocean or the Nordic Seas, acceleration-induced biases in sea-surface temperature evolution may occur with potential influence on the dynamics of the overlying atmosphere. […]

瞬时模拟在研究历史气候方面被广泛应用，因其能更优地与现有的替代数据相比较。然而，采用耦合气候模型进行的数千年瞬时模拟在计算上通常代价高昂。因此，在数值模拟中重现过去气候时，通常会实施多种加速技术。在本研究中，我们采用综合耦合气候模型CCSM3（社区气候系统模型3），对比了有无加速轨道强迫的瞬时模拟结果，针对当前间冰期和上一个间冰期。研究结果表明，在低纬度地区，间冰期地表气候长期变化的模拟并未受到加速技术（加速因子为10）的显著影响，因此，大规模模型与地表变量的数据对比并未受到阻碍。然而，在高纬度地区，地表气候与深层海洋直接相连，例如在南大洋或北欧海域，加速技术可能导致的海洋表面温度演变的偏差可能对上层大气动力学产生潜在影响。