Model EvaLuation using Observations, DIagnostics and Experiments Software (MELODIES)

MELODIES logoProject Team: Louisa Emmons (PI), Matt Dawson, Benjamin Gaubert, Gabriele Pfister, Simone Tilmes, Helen Worden, Avelino Arellano (U. Arizona), Gao Chen (NASA Langley)

MELODIES (Model EvaLuation using Observations, DIagnostics and Experiments Software) will be a modular framework to compare model results and observations of atmospheric chemistry. It is a component of the MUlti-scale Infrastructure for Chemistry and Aerosols (MUSICA) and is funded by NSF EarthCube. MELODIES will consist of components to manipulate both observations and model results, to allow for quantitative comparisons with long-term and field intensive observations.  MELODIES is being built upon an existing framework, MONET (Model and ObservatioN Evaluation Toolkit), in collaboration with NOAA scientists, Becky Schwantes (ESRL/CSD) and Barry Baker (ARL).  

This framework will facilitate:

  • Reading observational datasets with various spatial and temporal resolutions
  • Reading model output from regional or global models with structured or unstructured grids
  • Matching variable names and units between observations and model output
  • Matching observations and model results in space and time, applying observation operators and algorithms for quantitative comparison, as well as matching meteorological situations and other conditions
  • Plotting and analyzing comparisons: computing statistics with uncertainties, producing a performance matrix indicating limitations of comparisons 


MELODIES will be:

  • written to be user-friendly with easy customization
  • written in open-source programming languages, and made available through GitHub
  • well documented for easy use by the community


Earthcube Newsletter article Jan 2022

Poster presented at the Earthcube Annual Meeting: "MELODIES for MUSICA" (doi:10.6084/m9.figshare.14773524).

The framework design is illustrated below.  If you are interested in contributing to development, please contact Louisa Emmons.

MELODIES framework design




ACOM | Atmospheric Chemistry Observations & Modeling