北太平洋850和500hPa夏季副热带高压的年际和年代变化

The Interannual Variabilities and Decadal Variations of 850 and 500 hPa Summer North Pacific Subtropical High

利用NCEP\NCAR再分析位势高度场资料和Hadley中心SST资料,将北太平洋500和850hPa夏季副热带高压异常变化结合在一起进行了分析,发现夏季500和850hPa副高的位置和强度的年际和年代变化都有明显差异,并且850hPa副高远比500hPa副高稳定。上下两层除了同时增强和同时减弱外,还存在着500hPa增强850hPa减弱,以及500减弱850hPa增强等不同类型。相关分析表明,夏季500和850hPa副热带高压年际和年代异常变化与同期不同海区海表温度(SST)异常之间存在明显的关系。

Variabilities of 500 and 850 hPa summer North Pacific subtropical high （NPSH） are analyzed. Results show that significant interannual variabilities and decadal variations exist in 500 and 850 hPa sum- mer NPSH, and 850 hPa is much stable than 500 hPa. In addition to synchronous variation of strengthe- ning and weakening between the two layers, there are other modes that it strengthens at 500 hPa and weakens at 850 hPa, and vice versa. Besides, the relationship between the interannual variabilities and decadal variations of 500 and 850 hPa summer NPSH and sea surface temperature anomaly in different sea areas is also studied in this work.