北太平洋副极地海洋锋四季变异特征及其与中纬度大气的联系  

Seasonal variation characteristics of the subarctic front in North Pacific and its relationship with the mid-latitude atmosphere

作　　者：张然 陈圣劼 黄晶 ZHANG Ran;CHEN Shengjie;HUANG Jing(Key Laboratory of Transportation Meteorology of China Meteorological Administration,Nanjing Joint Institute for AtmosphericSciences,Nanjing 210041,China;Jiangsu Meteorological Observatory,Nanjing 210041,China;State Key Laboratory of Tropical Oceanography,South China Sea Institute of Oceanology,Chinese Academy of Sciences,Guangzhou 510301,China)

机构地区：[1]南京气象科技创新研究院,中国气象局交通气象重点开放实验室,南京210041 [2]江苏省气象台,南京210041 [3]中国科学院南海海洋研究所热带海洋环境国家重点实验室,广州510301

出　　处：《气象学报》2024年第4期427-442,共16页Acta Meteorologica Sinica

基　　金：江苏省自然科学青年基金(BK20231110);中国气象科学研究院基本科研业务费专项资金(2022Y026);江苏省青年科技人才托举工程(TJ-2022-053);中国科学院南海海洋研究所自主部署项目(SCSI02023QY01)。

摘　　要：基于高分辨率海洋与大气再分析资料,结合统计分析与动力学诊断,揭示了北太平洋副极地海洋锋区(Subarctic Oceanic Frontal Zone,SAFZ)强度四季变异的特征及成因,阐释了与SAFZ四季异常相伴随的中纬度大气环流异常特征及其对应的动力学过程。结果表明,SAFZ在秋、冬、春季较强,夏季相对较弱。海温经向平流过程是秋、冬、春季SAFZ强度维持的主导因素,而海-气界面净热通量交换过程对夏季SAFZ强度减弱起决定作用。在不同季节,伴随SAFZ强度变异,边界层湍流热通量发生变化,非绝热加热异常引起锋区上方低层气温经向梯度与大气斜压性的异常,进而导致大气瞬变涡旋活动异常。由瞬变涡旋涡度强迫异常主导,中纬度北太平洋及中国东部、东北部等地上空对应产生相当正压结构的大气位势高度场异常与风场异常,相应的大气环流异常场存在季节差异。Statistical analysis and dynamical diagnosis of high-resolution oceanic and atmospheric reanalysis data are conducted toreveal the characteristics and causes of seasonal intensity variation of the Subarctic Oceanic Frontal Zone(SAFZ)in the NorthPacific,and elucidate the characteristics of mid-latitude atmospheric circulation anomalies associated with the SAFZ seasonalvariation and corresponding dynamic processes.The results indicate that the SAFZ is strong in autumn,winter and spring,andrelatively weak in summer.The meridional advection process of Sea Surface Temperature(SST)is the dominant factor that maintainsSAFZ's intensity in autumn,winter and spring,while the net heat flux exchange process at the sea-air interface plays a decisive role inthe weakening of SAFZ's intensity in summer.Accompanied with the SAFZ's intensity variability in different seasons,the boundarylayer turbulent heat flux anomalies develop,and the diabatic heating anomalies lead to anomalies of low-level atmosphericmeridional temperature gradient and atmospheric baroclinicity above the SAFZ,and then lead to the anomalies of atmospherictransient eddy activities.Due to the dominant influence of anomalous atmospheric transient eddy vorticity forcing,equivalentbarotropic structure anomalies of atmospheric geopotential height field and wind field occur over the regions of mid-latitude NorthPacific and eastern and northeastern China,and the corresponding anomalous field of atmospheric circulation exhibiting seasonaldifferences.

关 键 词：副极地海洋锋区 海温异常 四季变异 大气瞬变涡旋强迫 中纬度大气环流 

分 类 号：P433.2[天文地球—大气科学及气象学]