A satellite-derived classification scheme for rapid maritime cyclogenesis

Abstract

The first category, referred to as the "emerging cloud head' is characterized by the formation of a cloud head poleward of an S-shaped cirriform band associated with a troposphere-spanning baroclinic zone. The second category, called the "comma cloud', involves development independent of a polar-front cloud bank and is distinguished by the transformation of an elongated cloud feature referred to as a "baroclinic leaf' into an increasingly well-defined comma shape. The third category, referred to as the "left exit', applies to cyclones that develop beneath the left-exit region of a jet streak embedded within diffluent flow downstream of the axis of an upper-level trough and that deepen in conjunction with the merger of a baroclinic leaf and a polar-front cloud band. The fourth category, referred to as the "instant occlusion' involves the merger of a cold-air cloud cluster and a polar-front cloud band within a confluent upper-level flow environment. -from Authors