Tropical cyclones dynamically interact with mesoscale oceanic features, like warm-core and cold-core eddies, which play a key role in their track and intensification. Warm (cold) core eddies, which are elevated (lowered) sea surface height structures with enhanced (diminished) heat content, respectively, can intensify (weaken) tropical cyclones by serving as a source of warm (cold) ocean water in the path of a storm. Oceanic anti-cyclone (cyclonic) The process of downwelling (upwelling) allows oceanic eddies to increase (reduce) heat content. In this study, we have conducted an Ocean Mixed Layer Heat budget analysis for distinct TCs over Bay of Bengal. Further we have examined the coherence between distinct ocean mixed layer budget terms and TC Genesis Potential Parameter (GPP) especially over warm and cold core eddies. Through this analysis, we found that the entrainment term has highest correlation with GPP, with correlation coefficient value of magnitude 0.68 with GPP, next to the entrainment the net heat flux term shows significant impact on GPP with correlation coefficient 0.42. Notably, unlike warm-core eddies, the pre-cyclonic relationship (5 days before passage) between mixed layer dynamics and GPP is absent in cold-core eddies. Furthermore, cold-core eddies have a lower association with different terms of mixed layer heat budget analysis and GPP than warm-core eddies. A prominent feature for warm-core eddies is that the net latent heat flux dominates in influencing GPP among the terms that determines net surface heat flux, however, such dominance of net heat flux is not observed for cold core eddies, which infers that the cold core eddy regions are relatively less influential in determining/impacting cyclone life cycle, compared to the warm core eddy regions. The present study offers valuable insights into the asymmetric role of oceanic eddies, particularly highlighting the pre-cyclonic ocean-atmosphere coupling over warm-core eddies, which should be incorporated into coupled forecast systems to enhance Tropical Cyclone intensity predictions in the Bay of Bengal.
Podapati et al. (Wed,) studied this question.