Evaluating the Roles of Dynamics, Physics, and Dynamics-Physics Interactions in CAM6 and EAMv1 Simulated Clouds and Aerosols over the Western North Atlantic Ocean

A climatology of short simulations with output at the 30-min timestep with and without nudging will be used to assess the roles of dynamics, physics, and dynamics-physics interactions in the simulation of low-level clouds, aerosols, and aerosol-cloud interactions in the Community Atmosphere Model (CAM6) and the Energy Exascale Earth System Model Atmosphere Model (EAMv1) over the Western North Atlantic Ocean. The difference between the unnudged simulation and observations conflates problems with the physics parameterizations and dynamics-physics interactions. Therefore, we break this down into two differences: the difference between the nudged simulation and satellite measurements and the difference between the unnudged and nudged simulations. The former is due primarily to problems with the physical parameterizations because of the prescription of dynamics done by the nudging, while the latter highlights the dynamics-physics interactions. Further model evaluations using in situ measurements of aerosols, clouds, and boundary layer turbulence from the ongoing Aerosol Cloud Meteorology Interactions over the Western Atlantic Experiment (ACTIVATE) campaign will aid in the identification of problems with the model physics and provide a path towards possible solutions.