Colloquium: Stephen Guimond

The range of spatial and temporal scales controlling the dynamics of geophysical fluid flows are vast and span several orders of magnitude from planetary-scale Rossby waves in the atmosphere to small-scale eddies responsible for viscous dissipation in the atmosphere and ocean.  This wide range of scales, and particularly the nonlinear interactions between them, pose significant difficulties for observational systems and numerical simulations that limit our understanding and predictive capability of extreme weather events. The frequency of extreme weather events (e.g. hurricanes, winter storms, wildfires) appears to be increasing in the current climate and it is important to assess the current state of knowledge and performance of predictive models for these disruptive events.

 

In this talk, I will describe my research efforts to understand the dynamics of hurricanes from a holistic view combining advanced remote sensing measurements and technology, theory and state-of-the-art numerical modeling. The focus is on understanding the nature and role of small-scale, turbulent perturbations and their nonlinear interactions with other scales during the intensification process.  Analysis of the vortex dynamics with community and research numerical models highlights the importance of the dynamic core and associated dissipation characteristics for simulating/predicting the propagation of energy among scales.

Extensions of the theoretical modeling work to a more realistic regime that involves interdisciplinary collaboration at UMBC will be described.