This study attempts to study the effects of asymmetric convection on tropical cyclone (TC) motion. The dynamics of such effects is also investigated. The data employed include reconnaissance aircraft data, aircraft radar data, dropsonde data, satellite cloud imageries and other relevant meteorological data sets. The aircraft radar reflectivity composites and satellite cloud imageries are used to study the distribution of convection around TCs. The dropsonde data provide the vertical temperature and wind structure. The other data sets are for calculating certain physical quantities such as divergence, dew-point depression, and vorticity to understand the physical processes associated with the different types of displacements. The TCs are categorized according to their track characteristics. The convection patterns in each category are then examined.
Preliminary results from radar reflectivity composites based on a few case studies indicate that TCs usually have an asymmetric convection pattern before and during their turning motion. After that their convection patterns become more evenly distributed as found in straight moving TCs. Low-level horizontal mean radial divergence in each quadrant calculated from the radial wind suggest that TCs with a turning motion usually have stronger convergence concentrated on one side. More cases are being studied to verify these effects on TC motion. The physics responsible for such effects will be presented at the conference.