Climate & Radiation Branch Seminar Series: Xiaohong Liu

Pacific Northwest National Laboratory

In this talk I will introduce an aerosol module and aerosol-cloud
interaction parameterizations in NCAR Community Atmospheric Model version 5
(CAM5). The modal aerosol module (MAM) predicts both aerosol mass and
number, and internal/external mixing between aerosol components. The aerosol
interface with a two-moment stratiform cloud microphysics considers cloud
droplet activation and ice nucleation in mixed-phase and cold ice clouds,
and ice supersaturation in cold ice clouds is also allowed.

I will present an evaluation of aerosol and cloud microphysics predictions
from CAM5 with observations. We find that a simplified MAM treatment (3-mode
version) which is designed for high-resolution global simulations captures
the essence of aerosol direct and indirect effects when compared with the
benchmark 7-mode treatment. Cloud microphysics in CAM5 captures the cloud
structure and liquid/ice partitioning in mixed-phase clouds evaluated with
the DOE ARM Mixed-Phase Arctic Cloud Experiment (M-PACE) observations. At
the end, aerosol-cloud-precipitation interactions from CAM5 are highlighted

Contact: Lazaros Oraiopoulos