Joint Seminar: Aerosol and Aerosol-Cloud Interactions in NCAR CAM5: Evaluation and Radiative Forcing
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 a detailed evaluation of aerosol prediction from a simplified MAM treatment (3-mode version) which is designed for high-resolution global models with observations. We find that this simplified version captures the essence of aerosol direct and indirect effects when compared with the benchmark 7-mode treatment. I will show an evaluation of cloud microphysics in CAM5 with DOE ARM Mixed-Phase Arctic Cloud Experiment (M-PACE) observations and how cloud structure and liquid/ice partitioning in mixed-phase clouds response to ice nuclei number. At the end, indirect forcing and anthropogenic black carbon absorption from CAM5 are highlighted.
Date
11.05.2010
Time
15:15 h
Place
- Bundesstr. 53, room 022/023
- Seminar Room 022/023, Ground Floor, Bundesstrasse 53, 20146 Hamburg, Hamburg
Speaker
Xiaohong Liu, Pacific Northwest National Laboratory