Tropical cyclone classification, complexity of tropical cyclone motion from a wide variety of external and internal dynamical forcing and their interaction, large-scale environmental flow, the axially symmetric circulation of the tropical cyclone, planetary vorticity (or ambient potential vorticity) gradient, processes involved in the binary cyclone interaction, trochoidal motion, the lower boundary forcing, large-scale steering, tropical cyclone movement in association with complex interaction of large-scale steering, track deflection relative to the environmental flow |