Supervisor: Michael Herzog (Geography)
Importance of the area of research:
Clouds are an important component in the Earth’s energy budget. Changes in cloud amount, cover and frequency are the largest uncertainty in our understanding of global climate. Observations and model simulations show that the cloud development is strongly modulated by the impact of cloud-aerosol interactions on precipitation forming processes, leading to changes in latent heat release that drives the general circulation of the atmosphere. Mixed phase clouds are common in convective events and are characterized by a complex interaction of various processes.
The goal of the PhD project is to simulate the formation of clouds and precipitation in convectively driven clouds within the framework of an existing cloud resolving atmospheric model (Herzog et al., 2003). Based on previous work (Herzog et al., 2004, Griffiths et al., 2012) an aerosol-cloud microphysical module will be developed that strives to describe relevant dynamical and microphysical processes by first principle.
What the student will do:
The aerosol-cloud microphysical module will combine an existing aerosol microphysical module that simulates particle size distributions with a synthesis of several existing cloud-microphysical schemes that predict mass and number of various hydrometeor classes. The main focus of this development will be the accurate treatment of the interaction between competing processes over time. The new module will be tested and validated against observations for different cloud regimes e.g. maritime stratocumuls and convective clouds.
Please contact the lead supervisor directly for further information relating to what the successful applicant will be expected to do, training to be provided, and any specific educational background requirements.
Griffiths PT, JS Borlace, PJ Gallimore, M Kalberer, M Herzog, FD Pope (2012): Hygroscopic growth and cloud activation of pollen: a laboratory and modelling study, Atmos. Sci. Lett., 13, 289-295, doi:10.1002/asl.397.
Herzog M, D Weisenstein, JE Penner, 2004: A Dynamic Aerosol Module for Global Chemical Transport Models: Model Description, J. Geophys. Res., Vol. 109, D18202, doi:10.1029/2003JD004405.
Herzog M, JM Oberhuber, HF Graf, 2003: A Prognostic Turbulence Scheme for the Non-hydrostatic Plume Model ATHAM, J. Atmos. Sci., 60(22), 2783-2796.