[GTP] IMAGe GTP Seminar at NCAR--David Schecter--TIME CORRECTION

[Silvia Gentile]

Hello,

The correct meeting time is 11:00am.

My apologies for the error.

Silvia Gentile

Silvia Gentile wrote:
> Hurricane Formation in Diabatic Ekman Turbulence
> David Schecter
> NorthWest Research Associates
> 
> 
> 
> 
> This study examines the emergence of hurricanes from chaotic swirling 
> motions in a 3-layer model of the tropical troposphere that includes 
> basic parameterizations of cumulus convection and air-sea interaction. 
> The chaotic flow is referred to as Diabatic Ekman Turbulence (DET), in 
> order to emphasize that cumulus convection and Ekman pumping are 
> critical to its behavior.  The time required for tropical cyclogenesis 
> in DET is examined over a broad range of sea-surface temperatures, 
> tropical latitudes, and surface exchange coefficients for moist entropy 
> and momentum. The mean results show sensible trends, but the specific 
> genesis time can vary significantly with subtle details of the initial 
> turbulence. Moreover, hurricanes do not always form. In the event that a 
> tropical depression develops into a hurricane, the process is highly 
> asymmetric. Intensification involves a shear-flow instability, the 
> production of mesovortices, and contraction of the basic circulation. 
> Despite the complex evolution, the intensification rate is largely 
> consistent with the expectations of a quasi-linear stability analysis. 
> Properties of mature hurricanes and the nature of their fluctuations are 
> briefly addressed in the context of the model.
> 
> 
> 
> Monday, February 2, 2009
> Foothills Laboratory 2, Room 1001
> Lecture 11:00am
> 
>