大气振荡与副高活动及四川盆地旱涝的关系

本文分析了1982年5～9月热带西太平洋地区,尤其是我国南海、菲律宾和印度尼西亚上空30～50天大气振荡与太平洋副高活动及四川盆地夏季旱涝的关系。结果表明:热带西太平洋上空大气低频振荡对太平洋副高有明显影响;四川盆地东、西部夏季降水30～50天振荡呈反位相变化;东(西)部降水低频振荡与热带西太平洋上空大气低频振荡呈反(同)位相关系。热带西太平洋上空大气低频振荡,通过引起太平洋副高中心、西伸脊点东西变动影响盆地夏季旱涝异常。

THE RELATIONS BETWEEN THE ATMOSPHERIC OSCILLATION AND THE SUBTROPICAL HIGH ACTIVITIES AND THE SICHUAN BASIN'S FLOOD-DROUGHT

In this paper, the relations between the 30-50 day atmospheric oscillation over the western tropical Pacific and subtropical high(SH) activities over the Pacific and the Sichuan Basin's flood-drought in summer are analysed. The result shows that the atmospheric low- frequency oscillation (ALFO) over the western tropical Pacific has a definite influence on SH over the Pacific. Within Sichuan Basin, the 30-50 day oscillation of rainfall in the east has a phase contrary to that in the west, and the phase of low-frequency oscillation of rainfall in the east (west) is contrary to (same as) that the ALFO over of the western tropical Pacific. Finally,it is pointed out that inducing the displacement of the center and west ridge-point of SH over the Pacific in the west-east direction, the ALFO over the western tropical Pacific results in the Sichuan Basin' s flood- drought anomaly in summer.