AMM

Abstract

Maintaining correlation between tracers and the dynamical wind and temperature fields with which they interact is a desirable trait of climate and weather models. A systematic, explicit test is developed to measure the consistency between a dynamical core's integration of the momentum equation, and its tracer transport algorithm. Potential vorticity is used as a diagnostic tool allowing direct comparison between the treatment of the dynamics and the integration of passive tracers. Several quantitative and qualitative metrics are suggested to measure this consistency including grid-independent probability density functions. Comparisons between the four primary dynamical cores of the National Center for Atmospheric Research's (NCAR) Community Earth System Model 1.0 (CESM) are presented. It is found that the finite volume (CAM-FV) and spectral-element (CAM-SE) dynamical cores perform better than the spectral-transform based Eulerian (CAM-EUL) and semi-Lagrangian (CA M-SLD) dynamical cores in the presence of a breaking wave.