混合海气耦合模式中的ENSO循环及其形成机制
ENSO SIMULATED BY A HYBRID COUPLED OCEAN-ATMOSPHERE MODEL AND ITS MECHANISMS
-
摘要: 在无异常外强迫的情况下, 将混合海气耦合模式进行了45年的模拟积分.结果表明:模式能较好地再现类似ENSO循环的热带太平洋海洋、大气的年际振荡, 模式ENSO循环的主周期为4~5年; 探讨了ENSO循环的负反馈机制, 指出:暖态的消亡与El Niño发展过程中太平洋东部不断增强的东风异常所产生的冷水上翻的加强以及纬向向西的冷平流有关; 冷态的消亡主要由赤道波的时滞效应所致.Abstract: A hybrid coupled ocean-atmosphere model is developed, with which a 45-year simulation is performed. Analysis shows that the model can reproduce ENSO interannual variability over the tropical Pacific. The principal period is about 4 to 5 years. The negative feedback mechanism of ENSO is investigated. The results show that the damping of warm phase can be attributed to the strength ening of the cold water upwelling accompanied with the strong anomalous easterly over the eastern Pacific during the developing period of El Nino and the cold advection along the equator. The damping of cold phase is mainly related to the delaying effects of the equatorial wave reflection.
-
-
[1] Zebiak S, Cane M.A model El Niño-Southern Oscillation.Mon.Wea.Rev., 1987, 115: 2262~2279. doi: 10.1175/1520-0493(1987)115<2262:AMENO>2.0.CO;2 [2] Philander S, Pacanowski R, Lau N and Nath M.Simulation of ENSO with a global atmospheric GCM coupled to a high-resolution tropical Pacific ocean GCM.J.Climate, 1992, 5: 308~329. doi: 10.1175/1520-0442(1992)005<0308:SOEWAG>2.0.CO;2 [3] Lau N, Philander S, Nath M.Simulation of ENSO phenomena with a low-resolution coupled GCM of the global ocean and atmosphere.J.Climate, 1992, 5: 284~307. doi: 10.1175/1520-0442(1992)005<0284:SOELPW>2.0.CO;2 [4] Neelin J, et al.Tropical air-sea interaction in general circulation models.Climate Dyn., 1992, 7: 73~104. https://www.osti.gov/scitech/biblio/181887-tropical-air-sea-interaction-general-circulation-models [5] Neelin J, Battisti D, Hirst A, et al.ENSO theory.J Geophys.Res., 1998, 103 (c7): 14261~14290. doi: 10.1029/97JC03424 [6] Battisti D S, Hirst A C.Interannual variability in a tropical atmosphere-ocean model: Influence of the basic state, ocean geometry and nonlinearity.J.Atmos.Sci., 1989, 46: 1687~1712. doi: 10.1175/1520-0469(1989)046<1687:IVIATA>2.0.CO;2 [7] Suarez M J, Schopf P S.A delayed action oscillator for ENSO.J.Atmos.Sci., 1988, 45: 3283~3287. doi: 10.1175/1520-0469(1988)045<3283:ADAOFE>2.0.CO;2 [8] Wu Aiming, Ni Yunqi.A hybrid coupled ocean-atmosphere model and ENSO prediction study.Adv.Atmos.Sci., 1999, 16 (3): 1~12. http://www.irgrid.ac.cn/handle/1471x/166972?mode=full [9] Wu Guoxiong, Liu Hui, et al.A nine-layer atmosphere general circulation model and its performance.Adv.Atmos.Sci., 1996, 13: 1~18. doi: 10.1007/BF02657024 [10] Zebiak S E.Tropical Atmosphere-Ocean interaction and El Nino/Southern Oscillation Phenomenon.Ph.D thesis, MIT, 1984, 261. [11] Rasmusson E, Carpenter T.Variations in the tropical sea surface temperature and surface wind fields associated with the Southern Oscillation/El Niño.Mon.Wea.Rev., 1982, 110: 354~384. doi: 10.1175/1520-0493(1982)110<0354:VITSST>2.0.CO;2