Abstract Tropical cyclones (TCs) in the Arabian Sea have intensified in recent decades, raising concerns about their oceanic and climatic impacts. This study examines sea surface temperature (SST), salinity (SSS), and chlorophyll‐a (Chl‐a) responses to 18 TCs (2006–2021), spanning Categories 0–5 across pre‐ and post‐monsoon seasons. The results reveal marked seasonal contrasts, with pre‐monsoon cyclones producing stronger but short‐lived SST cooling of 5–7°C, while post‐monsoon cyclones cause slightly weaker (4–6°C) but broader and more persistent anomalies that last over 10 days and cover up to 500,000 km 2 , more than twice that of pre‐monsoon cyclones. Post‐monsoon freshening reaches up to 5 PSU and remains 3–4 PSU after a week, compared to 2.5–4 PSU during pre‐monsoon cyclones. Weaker cyclones can induce stronger surface freshening through shallow mixing, whereas intense storms may upwell saltier subsurface waters, offsetting rainfall effects. Cyclone‐driven biological responses also differ, with post‐monsoon cyclones triggering sharp and sustained Chl‐a surges (up to 37 mg m −3 ), while pre‐monsoon stratification limits nutrient upwelling and phytoplankton growth. The broader influence of the strong post‐monsoon TCs extends beyond their immediate tracks, causing SST drops of 1°C–2°C in the Arabian Gulf, freshening of about 1 PSU in the semi‐enclosed Sea of Oman, and Chl‐a increases up to 4 mg m −3 across the northern Arabian Sea. Overall, seasonal upper‐ocean structure and cyclone intensity jointly determine the magnitude, extent, and persistence of physical and biological responses to TCs in the Arabian Sea.
Abdulmawjood et al. (Wed,) studied this question.