Seasonal variability of cyclone heat potential in the Bay of Bengal

Abstract

Monthly maps of cyclone heat potential (CHP) in the Bay of Bengal have been prepared by using Levitus climatological data set. Seasonal variability of CHP in the Bay of Bengal has been studied using the CTD data sets collected during five cruises during the period, 1993-1996. High value (greater than 30 kcal/cm sup(2)) of CHP coincided with anticyclonic gyre (ACG) and the low value of CHP (16 kcal/cm sup(2)) coincided with the cyclonic gyre (CG). This emphasizes the importance of gyres in the distribution of CHP, which play an important role in the intensification of cyclones/depressions. CHP is greater than 14 kcal/cm sup(2) over Andaman Sea, southern and Central Bay of Bengal where the generation and movement of cyclones take place during post south west monsoon season (October-November). A depression formed on 07.11.95 at 11 degrees N; 91 degrees E and intensified into a cyclonic storm by 8th November evening and crossed Orissa Coast on 9th November 1995. A few days before its formation, the value of CHP at the origin of this cyclone was about 20 kcal/cm sup(2). To understand the exact role of CHP in the formation and intensification of cyclones/depressions over Bay of Bengal, more intense and systematic data sets are essential