All Climate Events
Rare events, bistability and equatorial superrotation
Monday, July 16, 2018. 2:00PM. Rare events, bistability and equatorial superrotation. Corentin Herbert, ENS de Lyon, France. Sponsored by NOAA Geophysical Fluid Dynamics Laboratory. More information here.
Even though they have a very low probability of occurrence, rare events play a crucial part in many systems because they can have a huge impact. In the climate system, examples range from heat waves and winter storms to the more dramatic possibility of a bifurcation of the general circulation. In all cases, a major obstacle to study the dynamics of such events is that they are difficult to sample, either from observations or from direct numerical simulations with GCMs. In the first part of the talk, Herbert will show that numerical algorithms designed specifically to provide an efficient sampling of rare events alleviate this difficulty, and open the possibility to study atypical fluctuations and abrupt transitions in complex turbulent flows such as geophysical flows. In the second part, Herbert will discuss a potential example of bistability in the atmosphere: equatorial superrotation. They will focus on the conditions for bistability and the nonlinear mechanisms leading to it: Rossby wave resonance and the Hadley cell.
Location NOAA GDFL, 317 Seminar Room, Princeton, NJ.
Monday, 16 July 2018, 2:00