Measurements of light scattering can be used to quantify the concentration and composition of oceanic particles, and resolve biogeochemical processes spanning different time and space scales. In this paper, we analyze the first dataset, collected over wide spatial scales in the Red Sea, of particulate scattering (), particulate backscattering (), particulate absorption and chlorophyll‐a concentration [Chl_a]. We fit a three‐component conceptual model relating to [Chl_a], assuming a fixed background component (), and two additional components driven by small (<2m) and large phytoplankton (>2m) ( and , respectively). We extend the approach, for the first time, to the modeling of total particulate scattering (), allowing us to retrieve the backscattering ratio for each component in the model. We observe a high backscattering ratio for the background component which, when analyzed alongside measurements of particulate absorption, suggests it is likely dominated by non‐algal (rather than algal) particles. The high contribution of non‐algal particles to at low [Chl_a] may be related to the unique conditions in the Red Sea, or more broadly, characteristic of other oceanic conditions. The work illustrates how we can combine optical measurements with conceptual models, to understand better the composition of oceanic particles and ultimately, improve monitoring of marine biogeochemical processes. Our work will also be useful for developing regional ocean‐color models for the Red Sea.

中文翻译：

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与红海中粒子的性质有关的粒子散射和反向散射

光散射的测量可用于量化海洋颗粒的浓度和组成，并解决跨越不同时空尺度的生物地球化学过程。在本文中，我们分析了在红海中广泛收集的第一个数据集，其中包括颗粒物散射（），颗粒物反向散射（），颗粒物吸收和叶绿素a浓度[Chl_a]。我们采用与[Chl_a]相关的三成分概念模型，假设背景成分（）固定，并且由小浮游植物（<2 m）和大浮游植物（> 2 m）（分别为和）驱动两个附加成分。我们首次将方法扩展到总颗粒散射的建模（），这样我们就可以检索模型中每个组件的反向散射率。我们观察到背景成分的背向散射比很高，在与颗粒吸收测量一起进行分析时，表明它很可能是由非藻类（而不是藻类）颗粒所主导。非藻类颗粒对低[Chl_a]的高贡献可能与红海的独特条件有关，或更广泛地说，与其他海洋条件的特征有关。这项工作说明了我们如何将光学测量与概念模型结合起来，以更好地了解海洋颗粒的组成，并最终改善对海洋生物地球化学过程的监测。我们的工作对于为红海开发区域海洋颜色模型也将是有用的。