Inversion code used for the paper: Optimization of the Gaussian Dispersion Model Inversion for Estimating Facility Scale Methane Emissions in Canada by Shoma Yamanouchi et al., 2026

Inversion code used for the paper: Optimization of the Gaussian Dispersion Model Inversion for Estimating Facility Scale Methane Emissions in Canadaby Shoma Yamanouchi et al., 2026 Requirements:-Polyphemus (v1.8.1 or higher) must be installed at: ./inversion_code/Polyphemus-1.11.1/. In particular, the Gaussian plume module and atmospy module must be installed.-Polyphemus is a suite of air quality modeling system developed by CEREA (see https://cerea.enpc.fr/polyphemus/download.html for more details).-Note that on top of the Python 2 requirements of Polyphemus (see the installation guide on CEREA website), Python 3 must also be installed, and available to be called via the command "Python3"-The Python 3 environment requires Herbie, geopy, grib2io and nceplibs-g2c to be installed (we recommend installing these via conda). To run:Edit the sources.py file to configure source name, location, diameter and a priori (initial emission rate estimate). The file named main_inversion.py is the main file. Configure the main file to select the correct source. Input data file location must also be specified. Examples of input files can be found here: https://doi.org/10.18164/2264d3b1-761e-4521-9ebb-0b8124d1dab4 (if your input file naming structure is different, the file prefix/suffix variables in the main script may need to be altered).After configuring the variables, simply run the main function (i.e., "python main_inversion.py"). Note:As the code uses HRRR data published by NOAA for meteorology, the inversion will only work for North America. Source location can be edited in the sources.py file.