Atmospheric component of the MPI‐M Earth System Model: ECHAM6
Atmospheric component of the MPI‐M Earth System Model: ECHAM6
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DOI：
10.1002/jame.20015
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发表时间：
2013-06
影响因子：
6.8
通讯作者：
B. Stevens;M. Giorgetta;M. Esch;T. Mauritsen;T. Crueger;S. Rast;M. Salzmann;H. Schmidt;J. Bader
中科院分区：
文献类型：
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作者：
B. Stevens;M. Giorgetta;M. Esch;T. Mauritsen;T. Crueger;S. Rast;M. Salzmann;H. Schmidt;J. Bader
介绍了第六代大气环流模式ECHAM 6。相对于其前身的重大变化影响了短波辐射传输的表示、模型顶部的高度。对模式调整和对流触发进行了微小的更改。几种模式配置，不同的水平和垂直分辨率，进行了比较。随着水平分辨率提高到T63以上，模拟的气候有所改善，但变化是递增的;主要偏差似乎受到小尺度物理过程（如云和对流）参数化的限制。在中层大气中较高的垂直分辨率导致对流层上层温度偏差的系统性减少，并更好地代表中层大气及其变率模式。ECHAM 6代表了目前的气候，以及，或优于其前身。最显著的改善是热带外药物的流通。ECHAM 6仍然很好地反映了热带变化。然而，仍然存在一些偏见。这些包括低层云的代表性差，主要降水特征的系统性变化，陆地和海洋之间降水分配的偏差（特别是在热带地区），以及中纬度急流似乎不够向极。ECHAM 6对温室气体浓度增加的反应与ECHAM 5相似。混合分辨率（T63 L95）配置的平衡气候敏感性在2.9和3.4 K之间，对于47层模式来说稍大。云的反馈和调整对温室气体增加造成的变暖起到了积极作用。
ECHAM6, the sixth generation of the atmospheric general circulation model ECHAM, is described. Major changes with respect to its predecessor affect the representation of shortwave radiative transfer, the height of the model top. Minor changes have been made to model tuning and convective triggering. Several model configurations, differing in horizontal and vertical resolution, are compared. As horizontal resolution is increased beyond T63, the simulated climate improves but changes are incremental; major biases appear to be limited by the parameterization of small‐scale physical processes, such as clouds and convection. Higher vertical resolution in the middle atmosphere leads to a systematic reduction in temperature biases in the upper troposphere, and a better representation of the middle atmosphere and its modes of variability. ECHAM6 represents the present climate as well as, or better than, its predecessor. The most marked improvements are evident in the circulation of the extratropics. ECHAM6 continues to have a good representation of tropical variability. A number of biases, however, remain. These include a poor representation of low‐level clouds, systematic shifts in major precipitation features, biases in the partitioning of precipitation between land and sea (particularly in the tropics), and midlatitude jets that appear to be insufficiently poleward. The response of ECHAM6 to increasing concentrations of greenhouse gases is similar to that of ECHAM5. The equilibrium climate sensitivity of the mixed‐resolution (T63L95) configuration is between 2.9 and 3.4 K and is somewhat larger for the 47 level model. Cloud feedbacks and adjustments contribute positively to warming from increasing greenhouse gases.