South Eastern Arabian Sea (SEAS) is an upwelling dominated region, where the distribution of chlorophyll-a (Chl-a) is mainly controlled by basin-scale to mesoscale processes associated with seasonal reversal of winds and currents. The analysis of long-term satellite-derived Chl-a data revealed interannual variability in association with extreme climatic events. Chl-a data were obtained from Ocean Colour Climate Change Initiative (OC-CCI) which provides high resolution cloud free data for the Arabian Sea during summer monsoon season (June to September). Satellite measurements of Sea Level Anomaly (SLA), Sea Surface Temperature (SST) and sea surface wind data were also compiled from various sources. The monthly data for the above environmental variables during 1998 to 2016 were analysed as representatives of the possible causative physical processes influencing the variability in Chl-a. The time series and Hovmöller analyses shows that the maximum variability occurred during summer monsoon. This study shows that the interannual variability in Chl-a was prominently influenced by the underlying processes involved in coastal upwelling. The relative variability in Chl-a and associated environmental variables with these events was remarkable during strong El Niño-Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) events. Cross Correlation Function (CCF) analysis points out that Chl-a content is negatively correlated with IOD to an extent of one month lag or less whereas, ENSO does not indicate such direct relations. Further, the variability associated with IOD was more conspicuous than ENSO. The study elucidates the interannual variability of Chl-a and the overall influence of associated extreme events in the SEAS.

东南阿拉伯海（SEAS）是一个上升流为主的区域，叶绿素-a（Chl - a）的分布主要受与风和洋流季节性逆转相关的盆地尺度到中尺度过程的控制。对长期卫星衍生的 Chl- a数据的分析揭示了与极端气候事件相关的年际变化。氯-a数据来自海洋颜色气候变化倡议 (OC-CCI)，该倡议在夏季季风季节（6 月至 9 月）提供阿拉伯海的高分辨率无云数据。海平面异常 (SLA)、海面温度 (SST) 和海面风数据的卫星测量也从各种来源汇编。上述环境变量在 1998 年至 2016 年期间的月度数据被分析为影响 Chl- a变异性的可能原因物理过程的代表。时间序列和 Hovmöller 分析表明，最大的变化发生在夏季风期间。本研究表明 Chl- a的年际变化受沿海上升流所涉及的潜在过程的显着影响。在Chl-的相对变化一和与这些事件相关的环境变量在强厄尔尼诺-南方涛动（ENSO）以及印度洋偶极子（IOD）事件显着。互相关函数 (CCF) 分析指出 Chl- a含量与 IOD 呈负相关，滞后一个月或更短，而 ENSO 并未表明这种直接关系。此外，与 IOD 相关的可变性比 ENSO 更显着。该研究阐明了 Chl- a的年际变化以及 SEAS 中相关极端事件的总体影响。