The relationship between the East Asian polar front jet and mid-high latitude circulation during Meiyu season

The relationship between the East Asian polar front jet (EAPJ) and mid-high latitude circulation systems in East Asia is investigated based on the daily NCEP-NCAR reanalysis dataset. The results show that the meridional component of the EAPJ plays an important role in the change of East Asian jet stream, which accompanied with the mid-high latitude trough and ridge. Through the zonal wind dominates in the jet region when the EAPJ is strong. The meridional wind increases rapidly and becomes the dominant wind when the EAPJ decreases. Meanwhile, the trough-ridge systems are more intense, and the mid-high latitude circulation changes from zonal type to meridional type. Further analysis reveals that there are four centers of meridional wind anomalies in the EAPJ region: 80°E, 100°E, 120°E and 140°E, corresponding to four different mid-high latitude blocking locations and cold air paths.