Speaker: Dr. David Vishny, NYU
Title: "Old Book, New Pages: Novel Idealized Modelling and Statistical Frameworks for Demystifying Midlatitude Jet Dynamics"
Abstract:
As the study of midlatitude jet variability has matured over the past thirty years, an increasingly complex picture has emerged. New findings have prompted us to consider more than one EOF and more than one eddy feedback mechanism, as well as interactions of the mean flow with eddy kinetic energy and diabatic heating. In this talk, I will first discuss novel idealized simulations aimed at understanding how Atmospheric Cloud Radiative Effects (ACRE) impact the persistence of Southern Hemisphere jet variability. Next I will discuss new—and less oversimplified—statistical frameworks for conceptualizing midlatitude jet dynamics. One new statistical framework allows us to rigorously relate the persistence of jet variability to the momentum budget. Another new framework quantifies lagged interactions among the principal components of zonal mean zonal wind, eddy momentum flux convergence and eddy kinetic energy. In doing so, the framework finally offers plausible explanations of the power spectra, autocorrelations and cross-correlations of these dynamically-significant quantities.
Bio:
David Vishny is a postdoc at NYU’s Courant Institute who is broadly interested in geophysical fluid dynamics and data assimilation. He worked on a mixture of these two subjects with Profs. Nicholas Lutsko and Matthias Morzfeld during his PhD at Scripps Institution of Oceanography. Currently, he works with Prof. Edwin Gerber on implementing and optimizing atmospheric gravity wave parameterizations in GCMs. Outside of work, he enjoys playing soccer, doing yoga, whistling and throat singing.
In person attendance at this seminar is only open to Columbia University affiliates.
