Structure and Life Cycle of Tropical Cyclones

Abstract

The hurricane has three stages in its life cycle. In the genesis stage, a relatively disorganized array of clouds and squalls is associated with a wave perturbation in the easterly flow. The mature stage consists of a strong rotational circulation with a large axisymmetric component and clouds which are well organized about a center of low pressure. In the decaying stage, the circulation weakens, expands in size and becomes asymmetric about the center. We discuss the properties of the mature stage first. Then we can concentrate on the physical processes that lead to development of the mature structure during the formation stage. Finally, we describe the decaying stage of the hurricane.