关键词: “三核型”海温异常, 北极涛动, 北大西洋风暴轴

Abstract:

It has been well known that the triple － pattern interannual SST anomalies in the North Atlantic are principally forced by the dominant modes of Atmosphere variability，the North Atlantic Oscillation(NAO)or Arctic Oscillation(AO) ，but to what extent the North Atlantic SST anomalies can affect the Storm Track in the midlatitudes remains to be an issue． Here we estimate the response of North Atlantic Storm Track to SST anomalies by a GCM named CAM3． 0． The atmospheric CAM3． 0 was forced by the triple SST anomalies firstly，then the simulation results in winter (December to January)were compared with the NCEP/NCAR reanalysis data． We found the simulation results could reproduce the anomalies of Atlantic Storm Track and Jet accompanying the AO anomalies． Conclusions can be summarized as follows:when the SSTA was positive(negative) ，the storm track enhanced (weakened) ， and the jet exit region had a meridional displacement to polar (equator) ． The SSTA may influence the storm track through two ways，one is to change the lower atmospheric baroclinicity to affect the intensity of storm track directly，the other is to influence the meridional displacement of jet firstly，and then the jet influence the storm track． The positive feedback effection between eddies and mean flow becomes severe ( weakening)when SSTA is positive (negative) ．

Key words: the triple － pattern SST anomalies, Arctic Oscillation, North Atlantic Storm Track