Dynamical theories of tropical convection

Recent observations show that, in contrast to the middle-latitude atmosphere, the tropical atmosphere is very nearly neutral to reversible parcel ascent from the sub-cloud layer. This realisation, together with the failure of classical convection theory and Conditional Instability of the Second Kind (CISK) to explain many observed features of tropical convection, has led to a renewed interest in evaporatively driven downdrafts as the defining dynamical characteristic of mesoscale convective systems. After briefly reviewing the case against classical theories we summarise recent developments that focus on the role of downdrafts in organising and maintaining tropical convective systems.