Comparing the Spatio-Temporal Variability of Remotely Sensed Oceanographic Parameters between the Arabian Sea and Bay of Bengal throughout a Decade

The spatio-temporal variability of sea-surface temperature (SST), photosynthetically active radiation (PAR), chlorophyll-a (Chl-a), particulate organic carbon (POC) and particulate inorganic carbon (PIC) was evaluated in the Arabian Sea (ABS) and Bay of Bengal (BoB), from July 2002 to November 2014 by means of remotely sensed monthly composite Aqua MODIS level-3 data having a spatial resolution of 4.63 km. Throughout the time period under consideration, the surface waters of ABS (27.76±1.12°C) were slightly cooler than BoB (28.93±0.76°C); this was observed during all the seasons. On the contrary, the availability of PAR was higher in ABS (45.76±3.41 mol m^-2 d^-1) compared to BoB (41.75±3.75 mol m^-2 d^-1), and its spatial dynamics in the two basins was mainly regulated by cloud cover and turbidity of the water column. The magnitude and variability of Chl-a concentration were substantially higher in ABS (0.487±0.984 mg m^-3), compared to BoB (0.187±0.243 mg m^-3), and spatially higher values were observed near the coastal waters. Both POC and PIC exhibited higher magnitudes in ABS compared to BoB; however, the difference was substantially high in case of POC. None of the parameters showed any significant temporal trend during the 12-year span, except PIC, which exhibited a significant decreasing trend in ABS.