中纬度海温对北方冬季寒潮强度异常的协同影响  

Synergistic Effects of Mid-Latitude Sea Surface Temperature on Intensity Anomalies of Cold Waves in Winter of Northern China

作　　者：梁阔 李丽平[1] 任景华 施春华[1] LIANG Kuo;LI Liping;REN Jinghua;SHI Chunhua(Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster(NUIST),Ministry of Education,Nanjing University of Information Science&Technology,Nanjing 210044,Jiangsu,China;Xinhe County Meteorological Bureau,Aksu 842100,Xinjiang Uygur Autonomous Region,China)

机构地区：[1]南京信息工程大学气象灾害预报预警与评估协同创新中心/气象灾害教育部重点实验室,江苏南京210044 [2]新和县气象局,新疆维吾尔自治区阿克苏842100

出　　处：《高原气象》2023年第3期711-724,共14页Plateau Meteorology

基　　金：国家重点研发计划项目(2018YFC1505602)。

摘　　要：利用中国气象局国家信息中心提供的1980-2019年日最低温度资料、NCEP/NCAR逐月再分析资料和Hadley中心提供的逐月海表温度(SST)资料,分析了北方冬季寒潮强度异常时空特征及北半球中纬度海温异常(SSTA)对其影响机制。结果表明:(1)北方单站寒潮强度存在年际和年代际变化;1998年之前寒潮强度年代际变化更明显,1999年之后寒潮强度的年际变率更大。华北地区寒潮最强,内蒙古、甘肃和新疆交界处次之。(2)寒潮强度主要有全区一致型、东西反位相型及三极型异常分布,且全区一致型异常基本能反映强度总体时空变化特征。(3)北太平洋前春到冬季的类似太平洋年代际振荡负位相型(类“-PDO”型)SSTA、北大西洋前秋与冬季负SSTA有利于北方寒潮增强。秋季两大洋SSTA对寒潮强度的作用相当,冬季北大西洋SSTA影响更显著。(4)前春到前秋北太平洋类“-PDO”型SSTA及秋冬季北大西洋SSTA,激发出冬季负北极涛动(“-AO”)、正欧亚太平洋(“+EUP”)型、类太平洋-北美(“PNA”)型、负北大西洋涛动(“-NAO”)等遥相关型或波列异常;两大洋SSTA存在类似跨季节“接力”的关系,秋冬季两大洋协同作用,上游Rossby波能量向下游频散,持续加强“+EUP”等遥相关波列,使乌拉尔山高压脊和东亚大槽偏强,并有300 hPa北弱南强的急流配合,有利于高纬冷空气南下到我国北方地区辐合堆积,高低层环流异常配合,导致北方寒潮强度增强。Based on the daily minimum temperature data from 1980 to 2019 from the National Meteorological Information Center(China),the monthly NCEP/NCAR reanalysis data and sea surface temperature(SST)data from Hadley Center(UK),the spatial-temporal characteristics of the cold wave intensity in winter in northern China are analyzed,and the impact mechanisms of the mid-latitude SST anomalies(SSTA)in the northern hemisphere on it are also investigated.The results show that:(1)There are interannual and interdecadal variations in the cold wave intensity in northern China.Its interdecadal variability is more pronounced before 1998,and interannual variability is greater after 1999.The cold wave is strongest in North China,followed by the junction of Inner Mongolia,Gansu and Xinjiang.(2)The cold wave intensity mainly includes three kinds of anomalous distribution,namely,the regional consistent pattern,the east-west antiphase pattern and the tripolar pattern.The regional consistent pattern can basically reflect the overall spatial-temporal anomaly characteristics of the cold wave intensity.(3)The SSTA like a negative phase Pacific Decadal Oscillation("-PDO"-like)pattern in the North Pacific from pre-spring to winter and the negative SSTA in the North Atlantic from pre-autumn to winter are conducive to the enhancement of cold wave in northern China.The effects of SSTA on the cold wave intensity in the two oceans in pre-autumn are equivalent,while the impacts of the North Atlantic SSTA are more significant in winter.(4)The"-PDO"-like SSTA in the North Pacific from pre-spring to pre-autumn and negative SSTA in the North Atlantic from pre-autumn to winter can trigger the winter teleconnection pattern or wave train anomalies,such as the negative phase Arctic Oscillation("-AO"),positive phase Eurasian Pacific("+EUP")teleconnection wave train,Pacific-North America("PNA")-like pattern,negative phase North Atlantic Oscillation("-NAO").There is a similar cross-seasonal"relay"relationship between the two oceanic SSTA.In pre-autumn and winter

关 键 词：寒潮强度 时空特征 北太平洋海温 北大西洋海温 EUP遥相关波列 

分 类 号：P466[天文地球—大气科学及气象学]