CAJ | 학술논문

利用15年(1993～2007年)月平均的海表面高度(SSH)异常资料,分析了北太平洋海表面高度的年际变化的时窄结构,并研究J,热通量和风应力两个因子对其的强迫作用.结果表明,北太平洋年际时间尺度SSH变化的大值区在黑潮延伸区和西太平洋暖池区.EOF分解第一模态的卒间结构沿纬向呈带状分布,第二模态为沿经向呈带状分布.热通量强迫作用在中纬度的东北太平洋可以解释SSH年际变化40%以上.风应力对SSH的作用包括正压和斜压两个方面.正压Sverdrup平衡模型模拟的SSH年际变化较弱,仪能解释高纬度副极地环流西部的20%～40%.由大尺度风应力强迫的第一阶斜压Rossby波模型可以解释热带地区的20%～60%,中纬度中部的20%～40%,以及阿拉斯加环流东部和副极地环流西部的20%～60%.风应力强迫的一阶斜压Rossby波模型对SSH的强迫机理又可分为局地风应力强迫和西传Rossby波作用.其中,风应力的局地强迫作用(Ekman抽吸)在东北太平洋、白令海以及热带中部有显著的预报技巧,可以解释SSH年际变异的40%以上.Rossby波的传播作用在中纬度海域的副热带环流中西部和夏威夷岛以东起着重要作用,可解释20%～60%.
이용15년(1993～2007년)월평균적해표면고도(SSH)이상자료,분석료북태평양해표면고도적년제변화적시착결구,병연구J,열통량화풍응력량개인자대기적강박작용.결과표명,북태평양년제시간척도SSH변화적대치구재흑조연신구화서태평양난지구.EOF분해제일모태적졸간결구연위향정대상분포,제이모태위연경향정대상분포.열통량강박작용재중위도적동북태평양가이해석SSH년제변화40%이상.풍응력대SSH적작용포괄정압화사압량개방면.정압Sverdrup평형모형모의적SSH년제변화교약,의능해석고위도부겁지배류서부적20%～40%.유대척도풍응력강박적제일계사압Rossby파모형가이해석열대지구적20%～60%,중위도중부적20%～40%,이급아랍사가배류동부화부겁지배류서부적20%～60%.풍응력강박적일계사압Rossby파모형대SSH적강박궤리우가분위국지풍응력강박화서전Rossby파작용.기중,풍응력적국지강박작용(Ekman추흡)재동북태평양、백령해이급열대중부유현저적예보기교,가이해석SSH년제변이적40%이상.Rossby파적전파작용재중위도해역적부열대배류중서부화하위이도이동기착중요작용,가해석20%～60%.
15 years (1993～2007) monthly-averaged sea surface height anomalies (SSHA) are used to analyze their interannual spatial and temporal variability, also their thermodynamic and dynamic mechanisms are studied. The prominent interannual variability is located in the Kuroshio Extension and the western Pacific warm pool. By using the EOF method, the first mode of interannual SSHA is more likely zonal, while the second is much more meridional. The steric SSHA induced by the heat flux explains more than 40% of interannual SSHA in the midlatitudinal northeastern Pacific Ocean. The time-varying barotropic Sverdrup balance could explain 20%～40% in the western Subarctic gyre, whereas their interannual variations are indistinctive. Among the baroclinic mechanisms, the first baroclinic Rossby waves model forced by large-scale wind stress could explain the interannual SSHA 20%～60% in the tropical Pacific, 20%～40% in the central midlatitudes, and 20%～60% in the eastern Alaska gyre and western Subarctic gyre, respectively. The interannual SSHA induced by the local Ekman pumping has a local structure, which could explain more than 40% of the observed changes in the northeast Pacific Ocean, likewise in the Bering sea and central tropical Pacific Ocean. The westward propagating Rossby waves, derived from the difference between the Rossby waves model and Ekman pumping model simulating SSHA, could explain 20%～60% of the interannual SSH observations in the central and western subtropical gyre and east of the Hawaiian Islands.