本文选取1520线作为刻画850 hPa夏季西太副高年际变化的指标线,定义了西脊点、面积、脊线和北界指数。结果表明,夏季西太副高850 hPa的年际变化与500 hPa有一定差异,但850 hPa是较500 hPa研究夏季西太平洋副热带高压年际变化更为合适的一层。赤道太平洋海表面温度异常(SSTa)对850 hPa夏季西太副高的位置和面积的年际变化都有较显著的影响。
In this paper 1520 line is selected as the index line of the interannual variability of the 850 hPa SWPSH,defines the western ridge point,area,and the north ridge index.The results show that there some differences between 850 hPa and 500 hPa in the interannual variability of the summer Western Pacific subtropical hight(SWPSH),however,850 hPa is a more appropriate level than 500 hPa to investigate the interannual variability of SWPSH.Equatorial Pacific sea surface temperature anomalies(SSTa) have more significant impacts on the location and size of the interannual variability of SWPSH.