摘要
根据全球高分辨率的海洋环流模式 (POCM)的数值模拟结果 ,发现北赤道流区上层海洋流的季节内变化是以准 60天振荡为主 ,该准 60天振荡的振幅有年际变化。利用 2 .5层海洋模式 ,确定了NEC区纬向Rossby波解的频散关系。该关系表明 :北赤道流区行星波和波长小于 5 70km的Rossby波都为稳定波 ;波长小于 2 0 0 0km ,大于 5 70km的Rossby为不稳定波 ;最不稳定波的相速度和波长分别为 - 0 .1 45m·s- 1 和 785km。斜压不稳定是北赤道流区上层海洋准
Based on the numerical simulation output data of the global ocean model with high resolution (POCM), a quasi 60 day oscillation of the flow is mainly intraseasonal oscillation in the North Equator Current (NEC) region, and the amplitude of the quasi 60 day oscillation varies on an interannual time scale. Using the baroclinic 2.5 layer ocean model with dissipation, the dispersion relation for the Rossby wave is determined, which shows that in the NEC region the zonal planetary Rossby waves or the Rossby waves with shorter wavelength than 570km are stable; the Rossby waves with wavelengths longer than 570km and shorter than 2000km are instable waves. The phase speed and wavelengh of the most instable waves are -0.145m·s -1 and 785km, respectively. The baroclinic instability is the main formation mechanism of the quasi 60 day oscillation. The reason for the weaker quasi 60 day oscillation of the NEC in the west Pacific during 1997—1998 is discussed too.
出处
《海洋与湖沼》
CAS
CSCD
北大核心
2003年第1期94-100,共7页
Oceanologia Et Limnologia Sinica
基金
国家重点基础研究发展规划项目 (中国近海环流形成变异机理
数值预测方法及对环境影响的研究 )G1 9990 43 80 7号
国家自然科学基金资助项目 :499760 0 4号
海外杰出青年基金资助项目 :40 0 2 860 5号
