Abstract

Although the physics of mature hurricanes are fairly well understood, their genesis remains enigmatic. They can be shown to be finite amplitude instabilities, arising from a subcritical bifurcation of the radiative-convective equilibrium state of the Tropics. In this talk, I will suggest that the establishment of a mesoscale (~100 km in diameter) column of nearly saturated air extending through the troposphere is a necessary and perhaps sufficient condition for tropical cyclogenesis, and that such a development strongly suggests that generating systems must pass through a phase in which a cold-core cyclone exists at mid and upper levels of the troposphere.