Updating the experimental absorption cross sections for HITRAN2024

Many trace gases throughout Earth’s atmosphere are known to have a large potential to impact the radiation budget. The HITRAN database provides spectroscopic parameters and supplementary data in the form of line-by-line lists, absorption cross sections, collision induced absorption, water vapor continuum, and aerosol properties that enable molecular absorption to be modeled, which allows the radiation budget and radiative forcing to be determined. For HITRAN2024, in addition to increasing the number of molecules with line-by-line lists to 61, the absorption cross sections are receiving a substantial update. The update of cross sections makes use of many newly available experimental data and results in the addition over 100 molecules to the large number of molecules already represented as absorption cross sections in HITRAN2020 (Gordon et al. 2022). The absorption cross section update will also expand the range of experimental conditions available (i.e., temperatures, pressures, broadening gases, and resolutions) for many molecules that are present in Earth’s atmosphere. The new cross-sections have been a subjected to a validation process prior to being added to the database. This talk will showcase the absorption cross sections in HITRAN, and will highlight major updates for the 2024 compilation.

Funding from NASA grant 80NSSC23K1596 is acknowledged.

Reference: Gordon, et al., JQSRT 277, 107949 (2022). https://doi.org/10.1016/j.jqsrt.2021.107949