Subsurface chlorophyll maxima (SCM) significantly contributes to oceanic primary productivity, emphasizing the need to study its dynamics and governing mechanisms. We used datasets from various platforms to investigate relationships between the SCM characteristics (SCM depth (ZSCM), SCM magnitude (Chlmax), SCM thickness (TSCM)) and environmental variables modulated by various physical processes in the Northern Indian Ocean (NIO). In the Arabian Sea (western NIO), seasonal processes like convective mixing and upwelling, primarily regulated the SCM characteristics. In the Bay of Bengal (eastern NIO), SCM characteristics were jointly influenced by fresh water influx, barrier layer formation, presence of eddies, and the propagation of Kelvin and Rossby waves. Any changes in these oceanic processes, potentially driven by climate change, could therefore impact oceanic primary production. Additionally, a positive association obtained between Chlmax and downward CO2 flux, while a shallower ZSCM, associated with higher concentrations of DMS, indicated SCM's role in regulating atmospheric gases.

中文翻译：

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北印度洋地下叶绿素最大值动力学


地下叶绿素最大值 （SCM） 对海洋初级生产力做出了重大贡献，强调了研究其动力学和管理机制的必要性。我们使用来自各种平台的数据集来研究 SCM 特性 （SCM 深度 （ZSCM）、SCM 幅度 （Chlmax）、SCM 厚度 （TSCM））与北印度洋 （NIO） 各种物理过程调制的环境变量之间的关系。在阿拉伯海（NIO 西部），对流混合和上升流等季节性过程主要调节 SCM 特性。在孟加拉湾（NIO 东部），SCM 特征受到淡水流入、屏障层形成、漩涡的存在以及开尔文波和罗斯比波传播的共同影响。因此，这些海洋过程的任何变化（可能由气候变化驱动）都可能影响海洋初级生产。此外，Chlmax 与向下的 CO2 通量之间获得正相关，而较浅的 ZSCM 与较高浓度的 DMS 相关，表明 SCM 在调节大气气体中的作用。