Faculty of Civil Engineering, Shahrood University, Shahrood, Iran


In this study, univariate linear regression model was developed for monitoring secchi depth in the Caspian Sea using level 1b and level 2 data. The in-situ measurements were carried outduring 25 one-day campaigns in the Caspian Sea. In this study, 25 level 1b MERIS images were utilized and then converted to level 2 data using C2R processor. The ability of univariate linear regression for the extraction of secchi depth from level 1b and level 2 wasinvestigated. The results demonstrated that the level 2 data lead to better performance than level 1b data. The level 2 data are able to retrieve the secchi depth in the Caspian Sea with correlation coefficient and percent of absolute error about 0.86 and 28.6%, respectively. Finally, secchi depth map of Caspian Sea was retrieved from MERIS level 2 images using developed univariate empirical model.


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