Physical and biological response of the Arabian Sea to tropical cyclone Phyan and its implications

► Impact of tropical cyclone was immediate 2 °C SST-cooling due to strong wind-mixing. ► Biological response was 2-fold increase in productivity with 3-4 days lag time. ► Upward Ekman pumping and associated nutrient transport enhanced chlorophyll-biomass. ► Increased CO2 out-gassing of 0.123 Tg accounts for 85% November climatology.