Secchi Disk Depth is an important water quality measurement linked to many aspects of coastal and marine ecosystems. Understanding the role of this important indicator at regional scale requires synoptic observations through ocean color sensors, such as Moderate-Resolution Imaging Spectroradiometer (MODIS). In this study, the spatial and temporal distributions of Secchi depths were mapped over the North Arabian Gulf (NAG) from 2003 to 2020 using a regional Secchi depth model. Spatiotemporal patterns and trends of Secchi depths within the NAG were also investigated using time series analysis. Generally, the MODIS SDD retrievals revealed that NAG Secchi depths increased toward south and offshore waters of the study area. The northern areas exhibited very low Secchi depths with monthly means less than 1.7 m, whereas the middle and southern areas had the highest Secchi depths in all seasons with monthly means higher than 9 m. The Secchi depths were lower during the fall and winter seasons while higher during the spring and summer seasons with a general peak in June. The time series analysis approach used in this study can be a systematic guideline for the future remote sensing studies of Secchi depths and other water quality indicators over different geographical locations.

Secchi Disk Depth 是一项重要的水质测量，与沿海和海洋生态系统的许多方面相关。了解这一重要指标在区域尺度上的作用需要通过海洋颜色传感器进行天气观测，例如中分辨率成像光谱仪 (MODIS)。在这项研究中，使用区域 Secchi 深度模型绘制了 2003 年至 2020 年北阿拉伯湾 (NAG) 上的 Secchi 深度的空间和时间分布图。还使用时间序列分析研究了 NAG 内 Secchi 深度的时空模式和趋势。一般来说，MODIS SDD 反演显示 NAG Secchi 深度向研究区南部和近海水域增加。北部地区表现出非常低的 Secchi 深度，月均值小于 1.7 m，中南部各季节塞奇深度最高，月均值大于9 m。Secchi 深度在秋冬季节较低，而在春夏季节较高，一般在 6 月份达到高峰。本研究中使用的时间序列分析方法可以作为未来对不同地理位置的 Secchi 深度和其他水质指标进行遥感研究的系统指南。