Imaging Fourier-transform spectrometer datasets and MATLAB scripts for estimating flare combustion efficiency

This data deposit supports the results reported in the journal article “Quantitative assessment of long- and mid-wavelength infrared imaging Fourier-transform spectrometers for estimating flare combustion efficiency.” The repository contains processed datasets and MATLAB scripts used to quantify species mass flow rates from controlled laboratory experiments and field measurements of an in-service flare using imaging Fourier-transform spectrometers (IFTSs). Specifically, the deposit includes median-filtered absolute spectral radiance data cubes analyzed in Section 4 (Estimating mass flow rates from a laboratory-scale heated vent) and Section 5 (Estimating CE and identifying unburnt butadiene from a steam-assisted flare) of the manuscript. These hyperspectral data cubes were derived from long-wavelength infrared (LWIR) and mid-wavelength infrared (MWIR) IFTS measurements and represent the primary inputs used for plume species quantification. Also included are precomputed HITRAN-based interpolation tables of absorption cross-sections for all gaseous species quantified in the study, enabling reproducible spectroscopic modeling without requiring repeated line-by-line calculations. In addition, the repository contains two-dimensional velocity fields obtained by applying the Lucas–Kanade optical flow algorithm to the raw interferogram data cubes, which are required for estimating species mass flow rates. The accompanying MATLAB scripts implement the full analysis workflow used in the paper. These scripts regress modeled intensity spectra against the measured spectra from the median-filtered radiance data cubes to infer species column densities. The inferred column densities are then combined with the velocity field data to estimate species-specific mass flow rates. For the steam-assisted flare analysis, the updated scripts additionally quantify 1,3-butadiene mass flow rate and use the inferred species fluxes to estimate flare combustion efficiency. Together, the datasets and scripts provide a complete and reproducible framework for estimating gas emission rates and flare combustion efficiency from IFTS measurements, as well as for comparing the performance of LWIR and MWIR instruments in laboratory and field environments. The repository is intended to support transparency, reproducibility, and reuse by researchers working in infrared hyperspectral imaging, atmospheric spectroscopy, and industrial emissions monitoring.