An examination of climate sensitivity for idealised climate change experiments in an intermediate general circulation model
An examination of climate sensitivity for idealised climate change experiments in an intermediate general circulation model
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DOI：
10.1007/s003820000083
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发表时间：
2000-10-01
期刊：
影响因子：
4.6
通讯作者：
Shine, KP
中科院分区：
文献类型：
--
作者：
Forster, PM;Blackburn, M;Shine, KP
辐射强迫和气候敏感性已被广泛用作理解气候变化的概念。本工作进行气候变化试验与中间大气环流模式（IGCM），以检查的鲁棒性的辐射强迫概念的二氧化碳和太阳常数的变化。这IGCM已被专门开发为一个计算速度快的模型，但一个允许物理过程和大规模动态之间的相互作用，该模型允许许多长时间的积分相对较快地执行。它采用了第一个和准确的辐射传输方案，以及简单的对流和表面方案，和一个板状海洋，模拟气候变化机制对大气温度和动力学的影响，具有合理的复杂程度。IGCM运行在T-21分辨率与22个级别的气候学进行了比较，欧洲中期天气预报再分析中心的数据。当这些变化在全球范围内应用时，以及在地理上受到限制时（例如仅在陆地上），模型对二氧化碳和太阳能输出变化的响应进行了检查。CO2实验的气候敏感性比太阳实验高出约17%。高纬度强迫的气候敏感性比仅在低纬度强迫的气候敏感性高40%。结果发现，尽管模式反馈的差异，气候敏感性是大致恒定的分布范围内的CO（2）和太阳强迫。因此，至少在IGCM中，辐射强迫概念能够预测全球表面温度变化在30%以内，对于这里描述的扰动。因此，辐射强迫仍然是评估气候变化机制对地表温度的自然和人为影响的有用工具。
Radiative forcing and climate sensitivity have been widely used as concepts to understand climate change. This work performs climate change experiments with an intermediate general circulation model (IGCM) to examine the robustness of the radiative forcing concept for carbon dioxide and solar constant changes. This IGCM has been specifically developed as a computationally fast model, but one that allows an interaction between physical processes and large-scale dynamics; the model allows many long integrations to be performed relatively quickly. It employs a first and accurate radiative transfer scheme, as well as simple convection and surface schemes, and a slab ocean, to model the effects of climate change mechanisms on the atmospheric temperatures and dynamics with a reasonable degree of complexity. The climatology of the IGCM run at T-21 resolution with 22 levels is compared to European Centre for Medium Range Weather Forecasting Reanalysis data. The response of the model to changes in carbon dioxide and solar output are examined when these changes are applied globally and when constrained geographically (e.g. over land only). The CO(2) experiments have a roughly 17% higher climate sensitivity than the solar experiments. It is also found that a forcing at high latitudes causes a 40% higher climate sensitivity than a forcing only applied at low latitudes. It is found that, despite differences in the model feedbacks, climate sensitivity is roughly constant over a range of distributions of CO(2) and solar forcings. Hence, in the IGCM at least, the radiative forcing concept is capable of predicting global surface temperature changes to within 30%, for the perturbations described here. It is coneluded that radiative forcing remains a useful tool for assessing the natural and anthropogenic impact of climate change mechanisms on surface temperature.