印度洋海温异常对中高纬大气低频振荡影响的数值试验
NUMERICAL EXPERIMENTS OF EFFECT OF SSTA OVER INDIAN OCEAN ON ATMOSPHERIC LOW-FREQUENCY OSCILLATION IN THE EXTRATROPICAL LATITUDE
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摘要: 用数值试验的方法,应用强迫耗散准地转正压涡度方程的全球谱模式,在方程中考虑了偶(单)极子的热力强迫作用,并在三个行星波准共振的条件下,模式共积分90 d,得到:在偶、单极强迫热源和基本气流强度的共同作用下,三个行星波之间存在很强的波-波相互作用,且波动振荡呈现准双周和季节内振荡。同时偶、单极强迫源及基本气流的强度变化对中高纬大气的低频振荡调制作用不同。在准共振三波流函数场随时间变化的试验结果中,进一步证实了中高纬大气存在较好的低频振荡。Abstract: The numerical experiments on forcing dissipation and heating response of dipole (unipole) are carried out using global spectral model of quasi-geostrophic barotropic vorticity equation. For every experiment model integration is run for 90 days on the condition of three waves quasi-resonance. The results are given as follows: Under the effects of dipole (unipole) forcing source and basic flow intensity, there exist strong interaction among the three planetary waves, and there also exist quasi-two-week and intra-seasonal oscillation of the three planetary waves. In the meantime, the changes in the intensity of dipole or unipole forcing source and basic flow have different frequency modulation effects on LFO in the mid-high latitudes. The results of the stream function field of three quasi-resonant waves evolving with time proves further that the low-frequency oscillation exists in extratropical latitude.
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[1] FJORTOFT R.On the changes in the spectral distribution of kinetic energy for two-dimension non-divergent flows[J].Tellus,1953,5:225-230. [2] LONGUET-HIGGINS M A S,GILL A E.Resonant interactions between planetary waves[J].Proc Roy Soc Ser A,1967,299(1456):120-140. [3] 伍荣生.正压大气中波动共振与能量变化[J].中国科学(B),1979(2):195-203. [4] 陆维松.正压大气波动准共振和中高纬低频振荡[J].中国科学(B),1991(1):102-112. [5] LU Weisong.Four-wave resonance in a forced-dissipative barotropic atmosphere[J].Theor Appl Climatol,1996,55:221-228. [6] YAMAGATA T,HAVAHSI Y.A simple diagnostic model for the 30-50 day Oscillation[J].K Met Soc Japan,1984,62:709-717. [7] HOREL J D,WALLACE J M.Planetary-scale atmospheric phenomena associated with the Southern Oscillation[J].Mon Wea Rev,1981,109:813-829. [8] 曾庆存,梁信忠,张学洪,等.中国科学院大气物理研究所大气环流模式[C].北京:科学出版社,1990. [9] 陆维松,马淑杰,陶丽.非绝热加热对中高纬低频振荡的调频作用[J].南京气象学院学报,1998,21(3):336-345. [10] 邱明宇,陆维松,陶丽.ENSO事件对中高纬大气低频振荡的调频作用[J].南京气象学院学报,2004,27(3):365-373. [11] 邱明宇,陆维松,王尚荣.ENSO事件与北半球中高纬低频振荡[J].热带气象学报,2006,22(5):454-460. [12] COLUCCI S J,LOESCH A Z,BOSART L F.Spectral evolution of a blocking episode and comparison with wave interaction theory[J].JAS,1981,38:2092-2111. -
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