This is a past event.

Dr Graham Feingold, Research Scientist
NOAA's Earth System Research Laboratory, Boulder, Colorado
“Do aerosol particles have a significant impact on clouds?”
EPSSI Seminar Series, Richard Honrath Lecture
Dow 6414:00 pm

Shallow atmospheric convection exhibits fascinating cellular structures at scales of a few to several hundred kilometers. Configurations of relatively cloud-free open cell states, or much cloudier closed cell states can be clearly distinguished.
The difference in cloud fraction between these states has important consequences for the amount of shortwave energy reflected back to space, and therefore the role of these clouds in modifying energy flows in the climate system.
In this talk we will use both computationally intensive large eddy simulation and simple dynamical system analogs to explore self-organization, synchronization, and transitions between these two cloud field states. Analogies to other natural systems will be presented.
We will attempt to explain (i) why sometimes, even in the presence of drizzle, closed cellular convection persists, and (ii) why ship-generated aerosol particles emitted into open cells are not always effective at closing open cells. Finally we will comment on implications for proposed geo-engineering of marine boundary layer clouds.