Environmental Energetics aspects of anomalous Cyclogenesis over indian Ocean during 2013

摘要

An attempt has been made to understand the dynamics behind anomalous cyclogenesis over North Indian Ocean during 2013 cyclone seasons, from an atmospheric energetics point of view. For that various energy terms, their generation and conversion terms have been computed using NCEP/NCAR reanalysis data during different phases of the intense cyclonic vortices formed in 2013 over North Indian Seas. It is observed that maximum intensification of all the intense cyclonic vortices was associated with an enhancement in both conversions viz., from eddy available potential energy (AE) to eddy kinetic energy (KE) and zonal kinetic energy (KZ) to eddy kinetic energy (KE). Energetics analysis suggested that during intensification of the storms, dissipation of both eddy available potential energy ( AE )and zonal available potential energy (AZ) have taken place, suggesting the intensification of storms at the cost of AE and AZ. For all of these systems baroclinic eddy kinetic energy conversions i.e. from AE to KE dominates over barotropic eddy kinetic energy conversions i.e. from KZ to KE.Anomalous cyclogenesis in 2013, was partly attributed to a positive anomaly in moist static energy of the environment along with positive anomaly in baroclinic and barotropic eddy kinetic energy conversions during cyclone seasons over the region under study. Release of convective instability in the atmosphere can be partly attributed for anomalous cyclogenesis in 2013.