ENSO对江西省春季降水的影响

利用江西省83个站1970—2010年春季(3—5月)降水资料和NOAA的Ni觡o 3.4区海表温度资料,分析了ENSO事件对江西省春季降水的影响。结果表明,ENSO在衰亡年对江西省春季降水有显著的影响,ElNi觡o衰亡年春季江西地区降水偏多,易发生暴雨天气过程,江西北部和南部降水偏多最为显著;La Ni觡a衰亡年春季江西地区降水偏少,不易发生暴雨天气过程,江西东南部降水偏少最为显著。结合对应天气形势分析发现,El Ni觡o(La Ni觡a)衰亡年春季低层(850 hPa)南海的水汽输送偏强(偏弱)、上升运动偏强(偏弱)以及高层(200 hPa)辐散抽吸偏强(偏弱),是造成江西地区降水偏多(偏少)的主要原因。

EFFECT OF ENSO EVENTS ON SPRING PRECIPITATION IN JIANGXI PROVINCE

Using the 1970—2010 spring precipitation data of 83 stations in Jiangxi province and SST data afforded by NOAA,the effect of ENSO events on spring precipitation of Jiangxi is analyzed.The results show that the decay of ENSO events has significant influence on spring precipitation of Jiangxi.There are more rainfall（especially in north and south of Jiangxi）and storms in spring during El Nio event decay,while less rainfall（especially in southeast of Jiangxi） and storms during La Nia event decay.Analysis of weather situation suggests that during the spring when an El Nio（La Nia）event decays,the water vapor transport of lower level （850 hPa）from the South China Sea is stronger（weaker）,upward motion is stronger（weaker）and the high-level（200 hPa） pumping is stronger（weaker）in Jiangxi area,which are the main causes of more（less）rainfall in Jiangxi.