Using ARM data to investigate aerosol-cloud interactions for convective clouds in a global model
Authors
Lin Su — No Affiliation
Andrew Gettelman — National Center for Atmospheric Research (NCAR)
Shaocheng Xie — Lawrence Livermore National Laboratory
Xiaoliang Song — Scripps Institution of Oceanography
Guang Zhang — University of California, San Diego
Description
We incorporate a physically based two-moment microphysics scheme for convective clouds in the latest National Center for Atmospheric Research (NCAR) and Department of Energy (DOE) Community Atmosphere Model version5 (CAM5). We evaluate the cumulus, aerosol, and climate interactions using a more robust single-column version of NCAR CAM5 framework that incorporates ARM field data sets and observation periods. We developed scripts for running CAM5 using available ARM field campaigns (ARM95, ARM97, GATE111, Tropical Ocean Global Atmosphere Coupled Ocean Atmosphere Response Experiment [TOGA-COARE], Mixed-Phase Arctic Cloud Experiment [M-PACE], Tropical Warm Pool-International Cloud Experiment [TWP-ICE], Small Particles in Cirrus [SPARTICUS]). The representations of convective clouds, aerosol-cloud interaction, and cloud radiative effect (CRE) in convective clouds have been improved based on two deep convection field campaign cases (TWP-ICE for tropical case and ARM97 for subtropical case). The aerosol-cloud interaction and its effect on cloud development such as the delay of precipitation, cloud freezing levels, the optimum aerosol load, convection invigoration, and extending cloud lifetime have been evaluated through several aerosol sensitivity experiments.
