Spatio-Temporal Changes of Chlorophyll Concentration with Environmental Parameters Over the Gulf of Mannar, India

The present study investigated the spatio-temporal analysis of chlorophyll concentration with the variation of environmental parameters such as Aerosol optical depth (AOD) and sea surface temperature (SST) over the Gulf of Mannar (GOM) located in the southeastern part of India. The data derived from several satellites already provide information about the aquatic environment throughout the global waters. This study utilized the standard algorithms for the retrieval of Chl-a from the Moderate-resolution Imaging Spectroradiometer (MODIS) satellite sensor for a period of about 2002 to 2020. The monthly spatio-temporal variability of the Chl-a concentration with the changes in SST and AOD were analyzed over the Gulf of Mannar for the year 2011. This shows that many areas in the Gulf of Mannar have high chlorophyll concentrations of about 2 to 5 mg.m-3 in the single-day images for several months during 2011. Also, the variation in the SST is observed for several months during 2011, ranging from 28 to 31.5℃. The AOD values fall in the range of 0.09 to 0.12. In addition, the time series analysis of Chl-a, SST, and AOD were also studied for two different stations over the GOM. The result of the time series analysis explains that high chlorophyll concentration was observed during the colder months with low values in SST and AOD.