Intraseasonal Meridional Surges and Equatorial Convections during the Southern Hemisphere Summer

[摘要] Relationships between midlatitude cold surges and tropical convections are investigated utilizing 30-60 day filtered 850mb meridional winds and outgoing longwave radiation (OLR) data during the three Northern Hemisphere winters of 1980-83. The 30-60 day southerly surges over the eastern Indian Ocean off the west Australian coast act as the trigger and intensifier of low-frequency convective systems which systematically propagate eastward across the equatorial Indian Ocean and the western Pacific. In comparison, the northerly surges from the subtropical western Pacific (east of Philippines) tend to enhance equatorial convection between about 150°E and the date line, which is about 20 to 50 degrees of longitude downstream of the northerly blowing longitudes (120°-130°E).

[学科分类] 大气科学