气象学报2017，Vol.75Issue(4)：564-580,17.DOI:10.11676/qxxb2017.038
两类ENSO对中国北方冬季平均气温和极端低温的不同影响
摘要
Abstract
The responses of surface air temperature (SAT) in northern China to the eastern Pacific (EP) and central Pacific (CP) ENSO events during boreal winter are analyzed using reanalysis and observational data as well as specific atmospheric general circulation model (AGCM) experiments.Possible influences of ENSO events on regional cold extremes are also discussed.The North Atlantic Oscillation (NAO) is identified to be a bridge connecting ENSO signal and northern Eurasian temperature anomalies.Results show that ENSO influences northern China winter surface air temperature mainly through modulating the atmospheric circulation over the North Atlantic region, and thus changing the zonal temperature advection over northern Eurasia and the intensity of Siberian High.Moreover, the ENSO effects display prominent nonlinear characteristics due to different distributions of the tropical Pacific sea surface temperature (SST) anomalies during the two types of ENSO events.Corresponding to the two types of El Nio and EP La Nia winters, negative NAO-like atmospheric anomalies are evident over the North Atlantic region, which tend to inhibit the transport of warm and moist air from the Atlantic Ocean to Eurasian continent and thus favor a colder than normal winter in northern China.In particular, significant negative temperature anomalies during CP El Nio and EP La Nia winters are located in northeast China and the Ordos Loop and its vicinity area, respectively.The significant cold signal is confined in the north of Heilongjiang Province and the Greater Khingan Range during EP La Nia winters.In contrast, a positive NAO-like atmospheric anomaly pattern occurs over the North Atlantic region during the CP La Nia winter, but its positive anomaly center shifts westward.As a result, significant temperature anomalies are mainly confined in Europe and few significant signals can be observed in northern China.These observed results can be realistically reproduced by AGCM experiments.In addition, daily temperature in northeastern China tends to be colder than normal during EP El Nio and CP El Nio winters,indicating more frequent cold extremes.However, the linkage between La Nia events and cold extremes seems to be negligible.关键词
东部型ENSO/中部型ENSO/冬季平均气温/极端低温/中国北方Key words
Eastern Pacific ENSO/Central Pacific ENSO/Winter mean air temperature/Cold extremes/Northern China分类
天文与地球科学引用本文复制引用
汪子琪,张文君,耿新..两类ENSO对中国北方冬季平均气温和极端低温的不同影响[J].气象学报,2017,75(4):564-580,17.基金项目
全球变化与海气相互作用专项(GASI-IPOVAI-03)、国家自然科学基金项目(41475086、41675073)、江苏省六大人才高峰、333高层次人才工程和优势学科建设工程(PAPD)项目. （GASI-IPOVAI-03）
