气候与环境研究
氣候與環境研究
기후여배경연구
CLIMATIC AND ENVIRONMENTAL RESEARCH
2009年
5期
465-474
,共10页
ENSO模式%外强迫%优化扰动%模式参数
ENSO模式%外彊迫%優化擾動%模式參數
ENSO모식%외강박%우화우동%모식삼수
ENSO model%external forcing%optimal perturbation%model parameter
ENSO强度的影响因子是一个具有争议性的问题.作者探讨了一种理想的赤道高频纬向风强迫对ENSO强度的影响.将该问题转化为一类关于模式参数扰动的非线性最优化问题;基于所用的理论ENSO模式,研究了赤道高频纬向风强迫在调制ENSO强度中的角色.结果表明,对于E1 Ni(n)o和La Ni(n)a事件,存在两类外强迫,一类促进E1 Ni(n)o事件的发展却抑制La Ni(n)a事件的发展,另一类则抑制E1 Ni(n)o而促进La Ni(n)a事件的发展.这两类外强迫的主要区别在于初始相位的不同.相位决定了外强迫对ENSO事件是促进的还是抑制的,而外强迫的振幅和周期则决定了外强迫影响ENSO强度的大小.这些外强迫主要是通过海洋波动对斜温层深度的调节来影响ENSO事件的强度的.
ENSO彊度的影響因子是一箇具有爭議性的問題.作者探討瞭一種理想的赤道高頻緯嚮風彊迫對ENSO彊度的影響.將該問題轉化為一類關于模式參數擾動的非線性最優化問題;基于所用的理論ENSO模式,研究瞭赤道高頻緯嚮風彊迫在調製ENSO彊度中的角色.結果錶明,對于E1 Ni(n)o和La Ni(n)a事件,存在兩類外彊迫,一類促進E1 Ni(n)o事件的髮展卻抑製La Ni(n)a事件的髮展,另一類則抑製E1 Ni(n)o而促進La Ni(n)a事件的髮展.這兩類外彊迫的主要區彆在于初始相位的不同.相位決定瞭外彊迫對ENSO事件是促進的還是抑製的,而外彊迫的振幅和週期則決定瞭外彊迫影響ENSO彊度的大小.這些外彊迫主要是通過海洋波動對斜溫層深度的調節來影響ENSO事件的彊度的.
ENSO강도적영향인자시일개구유쟁의성적문제.작자탐토료일충이상적적도고빈위향풍강박대ENSO강도적영향.장해문제전화위일류관우모식삼수우동적비선성최우화문제;기우소용적이론ENSO모식,연구료적도고빈위향풍강박재조제ENSO강도중적각색.결과표명,대우E1 Ni(n)o화La Ni(n)a사건,존재량류외강박,일류촉진E1 Ni(n)o사건적발전각억제La Ni(n)a사건적발전,령일류칙억제E1 Ni(n)o이촉진La Ni(n)a사건적발전.저량류외강박적주요구별재우초시상위적불동.상위결정료외강박대ENSO사건시촉진적환시억제적,이외강박적진폭화주기칙결정료외강박영향ENSO강도적대소.저사외강박주요시통과해양파동대사온층심도적조절래영향ENSO사건적강도적.
What controls ENSO amplitude remains controversial. The authors explore the effect of a kind of ideal-ized equatorial high-frequency zonal wind forcing on ENSO amplitude.This problem is first transformed into a non-linear optimization problem related to model parameters.Based on a theoretical ENSO model,the role of high-fre-quency zoml wind forcing in modulating ENSO amplitude is explored.The results shoW that there are two kinds of high-frequency zonal wind forcings for ENSO events,where the differences lie in the amplitude of the forcing,the period,and the phase.These differences make one kind of forcing enhance the E1(n)o event,but suppress the La Ni(n)a event,while the other kind suppresses the E1 Ni(n)o event and enhances the La Ni(n)a event.The further analysis shows that the phase of the high-frequency zonal wind forcing determines the forcing whether enhances ENSO events or suppresses them,while the amplitude and period of the forcing control the degree of its effect on ENSO intensity.Both of these two types of forcings affect ENSO amplitude mainly by the adjustment of oceanic wave on the thermo-eline.