3.1.2. SST
Distribution of SST in the SEAS and the GoM has some characteristic behaviour (Supplementary Figure 2). The warmest SST in the study domain exists during the Pre-Monsoon, which is the first solar heating period in the region17,18. Following it, relatively cold water appears along the southwest coast of India and the GoM by June, and this cold SST situation prevails till October. It is also evident that much cooler SST (25-26°C) prevails along the Southwest coast of India compared to the GoM (~27°C) during the Southwest Monsoon (May to September). Also, the cooler water patch persists for longer duration in the southern tip of the southwest coast of India as it lasts from May to October, probably a cause of extended periods of upwelling there by local winds16. The upwelling signatures appear first at the southern tip of Indian subcontinent1 and later advances northward along with the coastally trapped Kelvin wave19,20. Though the cold water along the southwest coast of India disappears by October, relatively cold water reappears in the GoM by November. It lasts up to February (Northeast Monsoon), as a continuity of the cold water mass in the Bay of Bengal, intruded through the Palk Bay21.