The El Niño-Southern Oscillation (ENSO) has great impacts on the Indian Ocean sea surface temperature (SST). In fact, two major modes of the Indian Ocean SST namely the Indian Ocean Basin (IOB) and the Indian Ocean Dipole (IOD) modes, exerting strong influences on the Indian Ocean rim countries, are both influenced by the ENSO. Based on a combined linear regression method, this study quantifies the ENSO impacts on the IOB and the IOD during ENSO concurrent, developing, and decaying stages. After removing the ENSO impacts, the spring peak of the IOB disappears along with significant decrease in number of events, while the number of events is only slightly reduced and the autumn peak remains for the IOD. By isolating the ENSO impacts during each stage, this study reveals that the leading impacts of ENSO contribute to the IOD development, while the delayed impacts facilitate the IOD phase switch and prompt the IOB development. Besides, the decadal variations of ENSO impacts are various during each stage and over different regions. These imply that merely removing the concurrent ENSO impacts would not be sufficient to investigate intrinsic climate variability of the Indian Ocean, and the present method may be useful to study climate variabilities independent of ENSO.

厄尔尼诺-南方涛动（ENSO）对印度洋海面温度（SST）有很大影响。事实上，印度洋海温的两大模态，即印度洋海盆（IOB）模态和印度洋偶极（IOD）模态，对印度洋沿岸国家影响较大，均受ENSO影响。本研究基于组合线性回归方法，量化了 ENSO 并发、发展和衰减阶段对 IOB 和 IOD 的影响。去除ENSO影响后，IOB春季峰值消失，事件数量明显减少，而IOD事件数量仅略有减少，秋季峰值仍然存在。通过隔离每个阶段的 ENSO 影响，本研究表明 ENSO 的主要影响有助于 IOD 的发展，而延迟的影响促进了IOD阶段的转换并促进了IOB的发展。此外，ENSO 影响的年代际变化在每个阶段和不同地区是不同的。这意味着仅仅消除同时发生的 ENSO 影响不足以研究印度洋的内在气候变异，本方法可能有助于研究独立于 ENSO 的气候变异。