Seminar by Bettina Meyer

Atmospheric dynamics takes place on a wide range of scales: high- and low-pressure systems span thousands of kilometers, while energy dissipation takes place at micro-scale. To predict the weather or the long-term climate evolution in numerical models, all these processes have to be represented. This challenge is met by approximating the small-scale processes, such as dissipation, convection or the formation of clouds, in so-called parameterization schemes.
In this talk, I would like to give a brief overview about the work I did during my PhD, investigating parameterizations of turbulence, convection and clouds in the atmospheric boundary layer from a dynamical and statistical point of view.
In a second part, I will make the link to the current work of our group here at NBI, which is focused on the understanding of precipitation induced cold pools. Cold pools play an important role in the triggering and organization of convection. However, pinning down whether this is due to single cold pool fronts or collisions of multiple ones is not settled. Conceptual models show that this very distinction, single vs. multi-CP collisions, may be key to the character of the resulting spatial organization of thunderstorms, and related extreme precipitation events. I will show some preliminary results about cold pool collisions from our large-eddy simulations that may bring us closer to answering these questions.