The E3SM Diagnostics Package (E3SM Diags) is a Python-based Earth System Model (ESM) evaluation tool (with Python module name e3sm_diags), developed by the Department of Energy (DOE) Energy Exascale Earth System Model (E3SM) project. E3SM Diags provides tools for evaluating E3SM regridded and native output, as well as ESM data on regular latitude longitude grids, such as output from Coupled Model Intercomparison Project (CMIP) class models. E3SM Diags is modeled after the National Center for Atmospheric Research (NCAR) Atmospheric Model Working Group (AMWG) diagnostics package. During the version 1 and 2 release, E3SM Diags established a set of core diagnostics to evaluate the mean physical climate from model simulations and a set of process-oriented and phenomenon-based evaluation diagnostics orchestrated from the E3SM and broader scientific communities such as analysis of the Quasi-biennial Oscillation (QBO), El Niño - Southern Oscillation (ENSO), streamflow, diurnal cycle of precipitation, tropical cyclones, ozone and aerosols. An in-situ dataset from DOE’s Atmospheric Radiation Measurement (ARM) program has been integrated into the package for evaluating cloud and precipitation processes.

Recently, several new evaluations have been added to assess mixed-phase partition and analyze tropical waves using the Wheeler-Kiladis Diagram. Furthermore, to address aerosol bias in the model, a set of aerosol-centric diagnostics has been implemented with contributions from the E3SM Aerosol Working Group. Currently, there is a significant technical endeavor underway to migrate e3sm_diags to utilize a modern climate analysis library called xCDAT. This migration aims to enhance the capabilities and efficiency of the analysis process.

This work is performed under the auspices of the U. S. Department of Energy by Lawrence Livermore National Laboratory under contract No. DE-AC52-07NA27344.