As the phytoplanktons consume carbon dioxide, they significantly influence the global carbon cycle and thus, the global temperature by modifying sea surface temperature. Studies on the changes in chlorophyll–a (Chl-a) amount are therefore, key for understanding the changes in ocean productivity, global carbon budget and climate. Here, we report the cyclone-induced Chl-a blooms in the North Indian Ocean (NIO) using the ocean colour measurements from satellites for the past two decades (1997–2019). The average Chl-a concentration associated with cyclone-induced phytoplankton blooms is around 1.65 mg/m³, which is about 20–3000% higher than the average open ocean or pre-cyclone Chl-a levels, depending on the cyclones. In general, the phytoplankton bloom is inversely related to the translational speed (TS) of cyclones, as slower storms make intense Chl-a blooms. In addition to wind-induced upwelling and TS of cyclones, cold-core eddies also play a major role in enhancement of Chl-a when the cyclones encounter eddies on their track. It is observed that the cyclone-induced phytoplankton blooms are larger in the La Niña years than that in the El Niño and normal years. The amplitude of bloom is higher for the positive IOD years in Bay of Bengal, but for negative IOD years in Arabian Sea. Henceforth, this study provides new insights into the life cycle, seasonal changes, and magnitude of the cyclone-induced primary production, remote forcing and greenhouse mediated climate change in NIO.

随着浮游植物消耗二氧化碳，它们会通过改变海面温度而显着影响全球碳循环，进而影响全球温度。因此，研究叶绿素a（Chl-a）量的变化对于理解海洋生产力，全球碳预算和气候的变化至关重要。在这里，我们使用过去二十年（1997-2019年）的卫星海洋颜色测量报告了北印度洋（NIO）气旋引起的Chla绽放。与气旋引起的浮游植物水华相关的平均Chl-a浓度约为1.65 mg / m ³，这取决于气旋的平均水平，比开阔海洋或气旋前Chl-a的平均水平高20-3000％。通常，浮游植物的开花与旋风的平移速度（TS）成反比，因为较慢的风暴会产生强烈的Chl-a绽放。除了由风引起的上升流和旋风的TS以外，当旋风在其轨道上遇到旋风时，冷核涡旋在增强Chl-a方面也起着重要作用。可以看出，在拉尼娜年中，气旋引起的浮游植物水华比在厄尔尼诺和正常年份大。在孟加拉湾，IOD正值年的开花幅度较高，而阿拉伯海IOD负数年的开花幅度较高。此后，这项研究提供了有关气旋引起的初级生产的生命周期，季节性变化和强度的新见解，