Cooperative Institute for Research in the Atmosphere

Bernhard Haurwitz Memorial Lecture (2017): Potential Vorticity Aspects of Tropical Dynamics

Bernhard Haurwitz (1905-1986) was a member of our faculty for 13 years, teaching atmospheric dynamics and doing research on atmospheric tides. He was a pioneer in the study of tropical cyclone dynamics, writing papers on this subject before satellites, weather radars, and aircraft observations. He is also known for his analysis of “Rossby-Haurwitz waves.”

After a review of some of Bernhard’s contributions, the talk will focus on the potential vorticity aspects of tropical systems, especially tropical cyclones. We will try to understand how a tropical cyclone can become a hollow PV tower with values of PV exceeding 200 PV units. We will also discuss the role of the frictional boundary layer in establishing the eyewall and often a concentric eyewall, and also the role of barotropic instability in the breakdown of eyewall structures.