冬季北极涛动异常对北太平洋风暴轴的可能影响  

Possible influence of Arctic Oscillation anomalies on the North Pacific storm track during winter

作　　者：杨雯婷 朱伟军[1] 李欣 YANG Wenting;ZHU Weijun;LI Xin(Key Laboratory of Meteorological Disaster,Ministry of Education（KLME）/Joint International Research Laboratory of Climate and Environment Change（ILCEC）/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters（CIC-FEMD）,Nanjing University of Information Science ＆ Technology,Nanjing 210044,China;Xinzhou Meteorological Bureau of Shanxi Province,Xinzhou 034000,China)

机构地区：[1]南京信息工程大学气象灾害教育部重点实验室/气候与环境变化国际合作联合实验室/气象灾害预报预警与评估协同创新中心,江苏南京210044 [2]忻州市气象局,山西忻州034000

出　　处：《海洋气象学报》2018年第3期20-29,共10页Journal of Marine Meteorology

基　　金：国家自然科学基金项目(41575070;41075070);公益性行业(气象)科研专项(GYHY201306028)

摘　　要：基于美国国家海洋和大气局气候预测中心公报的北极涛动(Arctic Oscillation,AO)指数逐月数据以及美国国家环境预报中心和大气研究中心的1986—2017年逐日再分析资料等,运用回归和合成分析等方法,分析了北极涛动与北太平洋地区风暴轴的时间演变特征、两者之间的联系及AO异常影响风暴轴的可能机制。结果表明:1)风暴轴经度指数与纬度指数有显著正相关性,两者具有同步变化的特征,而这两者与风暴轴强度指数都呈负相关,但不显著。AO指数与北太平洋风暴轴强度呈显著正相关,且AO指数与风暴轴经度、纬度指数也呈正相关,但并不显著。2)在北极涛动强正(负)位相年份,风暴轴区域天气尺度滤波方差强(弱)、500 h Pa高度场上东亚大槽减弱(加深)、急流偏北偏强(偏南偏弱)、扰动动能增强(减弱)、斜压性增强(减弱)。可能影响机制是,异常变化的AO影响东亚大槽,改变急流强度,使斜压性发生变化,进而对风暴轴产生影响。On the basis of monthly Arctic Oscillation（ AO） data from NOAA（ Climate Prediction Center,National Oceanic and Atmospheric Administration） and daily reanalysis data from NCEP/NCAR（ National Centers for Environmental Prediction/National Center for Atmospheric Research） from 1986 to2017,by using regression and synthetic analysis,the temporal evolution characteristics of AO and the North Pacific storm track,the relations between AO index and storm track index（ including intensity,longitude,latitude index）,and the possible physical mechanism of AO anomalies on the storm track are studied. The results are as follows. 1） The longitude index of the storm track has significant positive correlation with the latitude index of the storm track,and they both have the feature of synchronouschange,but they both have non-significant negative correlation with the intensity index of the storm track.The correlation between AO index and the intensity of the North Pacific storm track is significantly positive. The correlation between AO index and the longitude/latitude of the storm track is positive,but not significant. 2） Further analysis indicates that,in the years when AO is in strong positive/negative phase,the synoptic-scale filtering variance becomes stronger/weaker, the East Asia major trough becomes weaker/stronger at the level of 500 h Pa,the jet stream moves northward/southward and becomes stronger/weaker,the disturbance kinetic energy becomes stronger/weaker,and the baroclinicity becomes stronger/weaker in the areas of the North Pacific storm track. The possible influence mechanism is that the anomalous changes of AO affect the East Asia major trough,change the intensity of westerly jet stream and the baroclinicity,and then exert an effect on the storm track.

关 键 词：北极涛动异常 北太平洋风暴轴 相关关系 影响机制 

分 类 号：P732[天文地球—海洋科学]