江淮流域旱涝年份准定常行星波分布与平均纬向风速的差异

利用欧洲数值预报中心1980—1989年6—8月资料，讨论了80年代江淮流域夏季旱涝年份亚洲地区平均纬向风速和准定常行星波分布的差异。旱年类与涝年类相比，热带东风急流强度偏强，纬度位置偏南；副热带急流强度相近，位置偏北。旱年（涝年）类的夏季准定常行星波的分布反映了菲律宾周围水域上空和青藏高原地面的热源均为偏强（弱）的异常外源强迫的结果。二者的主要差异表明，在中高纬度振幅大值区，旱年类纬度位置较涝年类偏北几个纬度。厄尔尼诺与反厄尔尼诺年份之间，准定常行星波各纬向波数的振幅距平分布基本上具有完全相反的型式，亚

The Differences of Quasi-stationary Planetary Wave Distribution and Mean Zonal Wind Speed Between Drought and Flood Years in Summer in the Changjiang and Huaihe River Basins

The differences of quasi-stationary planetary wave distribution and mean zonal wind speed between drought and flood years in summer during 1980’s in the Changjiang and Huaihe River Basins are examined. It is indicated that the central intensity and location of tropical easterly jet are stronger and more southerly in drought years than in flood years. But the latitude location of subtropical westerly jet is more northerly. The summer quasi-stationary planetary wave distributions in drought (flood) years reflect the external source forcing effect by strong (weak) heat source anomaly over around the Philippines and the Tibet Plateau. The differences appear mainly in latitude location relative to large value region of wave amplitude for the mid-high latitudes. The amplitude anomaly distributions of zonal wave numbers of quasi-stationary planetary wave in the E1 Nino events are contrary to those in La Nina events.