10. March: Wouter Mol, University of Vien
Abstract: Clouds influence the atmosphere's radiation balance, but cloud formation and lifetime itself is also influenced by radiation. In ongoing work, I'm studying the impacts of mid level clouds, as these are common, yet difficult to resolve in models and, in my review, under-studied.
First, I will discuss the various types of mid level clouds and their presumed origins. Second, I will show observed climatology and some regional hot spots of mid level clouds based primarily on satellite observations. One such hot spot is the Sahel region in Africa, which shows a tri-modal cloud climatology with height, with mid level clouds peaking just above the freezing level (~ 5 km).
Thirdly, I will show the experimental design and preliminary results of two hypothesized types of impacts mid level clouds have on the atmosphere, and how these impacts might feed back to the their own formation. These two impacts relate to cloud overlap influencing cloud lifetime through altering cloud radiative heating and modifications to atmospheric stability and thus convective mass flux. These experiments are numerical idealizations of clouds using large-eddy simulation, which will also double as a demonstration of the difficulty of representing these clouds in the middle troposphere.
https://bokuvienna.zoom.us/j/95795467199
wouter.mol(at)univie.ac.at