Seasonal Evolution of Subtropical Anticyclones in the Climate System Model FGOALS-s2

• Published in: Advances in atmospheric sciences Vol. 30; no. 3; pp. 593 - 606
• Main Author: 刘屹岷 胡俊 何编 包庆 段安民 吴国雄
• Format: Journal Article
• Language: English
• Published: Heidelberg SP Science Press 01.05.2013; Springer Nature B.V; State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029; State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029%Nanjing University of Information Science and Technology, Nanjing 210044
• Subjects: Anticyclones; Atmospheric circulation; Atmospheric models; Atmospheric physics; Atmospheric Sciences; Carbon monoxide; Climate; Climate system; Earth and Environmental Science; Earth Sciences; Evolution; Fluid dynamics; Geophysics/Geodesy; Heating; Hydrodynamics; Marine; Mathematical models; Meteorology; Oceans; Seasons; Simulation; Spring; Spring (season); Summer; Troposphere; Winter; 亚热带; 反气旋环流; 国家重点实验室; 大气物理研究所; 季节演变; 数值模拟; 气候系统模式; 西太平洋地区; subtropical anticyclone simulation; components of diabatic heating; climate system model FGOALS-s2; seasonal evolution
• ISSN: 0256-1530; 1861-9533
• DOI: 10.1007/s00376-012-2154-0

The simulation characteristics of the seasonal evolution of subtropical anticyclones in the Northern Hemisphere are documented for the Flexible Global Ocean-Atmosphere-Land System model, Spectral Version 2 （FGOALS-s2）, developed at the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, the Institute of Atmospheric Physics. An understanding of the seasonal evolution of the subtropical anticyclones is also addressed. Compared with the global analysis established by the European Centre for Medium-Range Forecasts, the ERA-40 global reanalysis data, the general features of subtropical anticyclones and their evolution are simulated well in both winter and summer, while in spring a pronounced bias in the generation of the South Asia Anticyclone（SAA） exists. Its main deviation in geopotential height from the reanalysis is consistent with the bias of temperature in the troposphere. It is found that condensation heating （CO） plays a dominant role in the seasonal development of the SAA and the subtropical anticyclone over the western Pacific （SAWP） in the middle troposphere. The CO biases in the model account for the biases in the establishment of the SAA in spring and the weaker strength of the SAA and the SAWP from spring to summer. CO is persistently overestimated in the central-east tropical Pacific from winter to summer, while it is underestimated over the area from the South China Sea to the western Pacific from spring to summer. Such biases generate an illusive anticyclonic gyre in the upper troposphere above the middle Pacific and delay the generation of the SAA over South Asia in April. In mid- summer, the simulated SAA is located farther north than in the ERA-40 data owing to excessively strong surface sensible heating （SE） to the north of the Tibetan Plateau. Whereas, the two surface subtropical anticyclones in the eastern oceans during spring to summer are controlled mainly by the surface SE over the two continents in the Northern Hemisphere, which are simulated reasonably well, albeit with their centers shifted westwards owing to the weaker longwave radiation cooling in the simulation associated with much weaker local stratiform cloud. Further improvements in the related parameterization of physical processes are therefore identified.