Abstract：Rapid changes in Tropical Cyclone (TC) structure and intensity are the most difficult aspects of TC forecasting. The intensity and structural changes associated with rapid intensification (RI) and rapid weakening (RW) instances of TCs of North Indian Ocean (NIO) are analysed based on 5 cases each for RI and RW. The vertical profiles of heat (Q1) and moisture (Q2) based on heat and moisture budget equations are analysed to bring out the role of diabatic heating during the RI and RW processes. The associated structural changes are analysed based on the Fourier first order wave number-1 asymmetry in the precipitation patterns associated with RI and RW instances. During RI process, there are 2 predominant Q1 maxima associated with latent heat release near the TC centre, one in the upper troposphere and the other in the lower troposphere. During RW process, there is a single dominant Q1 and Q2 maxima in the mid-troposphere. Regarding the structural changes, there is a pronounced front-back asymmetry in both RI and RW cases. The asymmetry amplitude in the inner core is lower in the case
of RI events but, is quite high for RW events. Thus, RW events are characterised by large convective asymmetry.
Dr. S.BALACHANDRAN, India Meteorological Department, Regional Meteorological Centre, 6 College road, Chennai 600006, India. E-mail: email@example.com
Cite this article:
B.GEETHA and S.BALACHANDRAN, 2016: Diabatic Heating and Convective Asymmetries During Rapid Intensity Changes of Tropical Cyclones over North Indian Ocean. Tropical Cyclone Research and Review, 5(1-2), 32-46.