西太平洋赤道雨与E1 Nio

EQUATORIAL RAIN IN WEST PACIFIC AND EL NIO EVENT

本文通过统计分析,发现西太平洋赤道雨连续3个月出现降水量为正距平,且距平大于200mm时,则未来1—2个月内发生厄尔尼诺(E1 Nino,下同)事件的可能性十分大。由这一相关事实出发,并从动力学进行探讨。初步认为,西太平洋赤道雨是通过降水量连续偏多改变赤道太平洋上空的Walker环流形势,产生Kelvin波,使赤道太平洋表层有热量自西向东传,叠加在赤道东太平洋和秘鲁外海表面的辐射加热场上,从而引发厄尔尼诺事件的出现。

Through statistical analysis it has been found that, if monthly precipitation positive anomaly for continuative three months in Equatorial West Pacific occurs, and the sum of monthly precipitation positive anomaly of three months is big enough,then the possibility for genesis of the El Nino event is great.From this statistical fact, further exploration has been made from the dynamical point, It is preliminary considered that the continuous positive anomaly in equatorial precipitation in West Pacific alters Walker circulation topography at the upper air of Equatorial Pacific and generates the Kelvin waves in the upper ocean. It transports heat of the Equatorial Pacific surface layer from west to east, which add to the radiation heating field of East Equatorial Pacific and offshore Peru, thus leading to genesis of the El Nino event.