OP-E7.4 E3SM SCM

Abstract

This presentation will discuss the modernization of the E3SM single-column model, which had received little upkeep since it was developed as part of the Community Atmosphere Model more than a decade ago. We will discuss the changes to the SCM we found necessary for producing scientifically credible results. We will also introduce our audience to the online library of run scripts, input data, and validation data we made available for a variety of case studies. This data includes several new multi-year SCM case studies from ARM sites.  Finally, we will discuss the major modernization task of the SCM, which involves allowing the SCM to be run with the Spectral Element dynamical core instead of requiring SCM simulations to use the outdated Eulerian dycore.  This development will finally make it feasible to “replay” a column of an E3SM run.  This capability is extremely useful for debugging GCM crashes, but would also be useful for investigating stubborn biases in E3SM (for example, poor marine stratocumulus), and for investigating why SCM sensitivity to perturbations hasn’t always been a good proxy for GCM sensitivity.