The influence of phase and amplitude of Indian Ocean Dipole (IOD) and El Niño Southern Oscillation (ENSO) on the interannual variability of the Indian summer monsoon rainfall (ISMR) over North East India (NEI) has been studied first time from 1960 to 2015. The independent contribution of different phases and amplitude of IOD and ENSO in the interannual variabilities of ISMR over NEI is explained by correlation and found that precipitation decreases due to anomalous wind vector from the Bay of Bengal (BOB) to the Sumatra region. The northeasterly wind also reduces the advecting moisture towards NEI during pure positive IOD event years (PPIOD) at 850 hPa. Conversely, a positive anomaly was found in the BOB during the Pure El Niño event years (PEN) due to the SST anomaly in the east-central Pacific Ocean before the beginning month of the summer monsoon. Similarly, pure negative IOD event years (PNIOD) also show positive anomaly, which results in the moderate southwest monsoon. Because of the random composite circulation field, the changes in mean monsoonal rainfall are not much significant during the pure La Niña event years (PLN). These studies show the direct influence of the ENSO and IOD phenomenon on ISMR over NEI.

首次研究了印度洋偶极子 (IOD) 和厄尔尼诺南方涛动 (ENSO) 的相位和振幅对 1960 年至 2015 年印度东北部 (NEI) 的印度夏季风降雨 (ISMR) 年际变化的影响. IOD 和ENSO 的不同相位和幅度对NEI 上ISMR 年际变化的独立贡献用相关性解释，发现由于从孟加拉湾（BOB）到苏门答腊地区的异常风矢量，降水减少。在 850 hPa 的纯正 IOD 事件年 (PPIOD) 期间，东北风还减少了向 NEI 的平流水分。反过来，由于夏季季风开始月份之前太平洋中东部的海温异常，在纯厄尔尼诺事件年（PEN）期间在 BOB 中发现了一个正异常。同样，纯负 IOD 事件年 (PNIOD) 也显示正异常，这导致了温和的西南季风。由于随机复合环流场，在纯拉尼娜事件年（PLN）期间平均季风降雨量的变化并不显着。这些研究显示了 ENSO 和 IOD 现象对 NEI 上的 ISMR 的直接影响。