Absorption cross sections for air- and H2O-broadened CO2 in the 1.6 µm and 2 µm regions (including continuum) and air- and self-broadened H2O in the 1.6 µm region

Remote sensing of CO2 requires high accuracy spectroscopic reference data. This requirement can only be fulfilled with many line parameters per line in combination with highly sophisticated line models. When using these line parameters the user is faced with the problem of implementation and validation, which can be rather time consuming and error prone. The way out is that the originator of the line parameters makes the data available in form of absorption cross sections, as it is done for the OCO missions defining and utilizing the ABSCO database [1]. The present absorption cross sections were obtained from line parameters and continua published under the five ZENODO links below, measurements and analysis were carried out in the frame of the ESA-funded ISOGG project. The CO2 absorption cross sections are given in the ranges 4750-5175 cm-1 and 5970-6575 cm-1 for 12CO2 (and other isotopologues except for 13CO2), 13CO2, and the CO2/air continuum with a wavenumber spacing of 0.0025 cm-1. The pressure, temperature, and humidity grids were adopted from the ABSCO database. The intensity depletion (for pure CO2 see [2]) was also taken into account. In case of H2O only the range 5970-6575 cm-1 is covered. The format of the database is HDF5 (Hierarchical Data Format), which is a binary to be accessed with corresponding software libraries. ZENODO entries of line parameter databases (also including measurement databases) Measurement database and line parameter database for air- and H2O-broadened CO2 in the 5970-6575 cm-1 region including continuum Measurement and line parameter database CO2 5975-6575 cm-1 including intensity depletion and continua Measurement database and line parameter database for air- and H2O-broadened CO2 in the 4750-5175 cm-1 region including continuum Self broadening measurement and line parameter database CO2 4750-5175 cm-1 Measurement database and line parameter database for air- and self-broadened H2O in the 5970-6575 cm-1 region [1] Vivienne H. Payne et al., Absorption coefficient (ABSCO) tables for the Orbiting Carbon Observatories: Version 5.1, Journal of Quantitative Spectroscopy and Radiative Transfer, Volume 255, 2020, 107217, https://doi.org/10.1016/j.jqsrt.2020.107217. [2] M. Birk, C. Röske, G. Wagner, The pressure dependence of the experimentally-determined line intensity and continuum absorption of pure CO2 in the 1.6µm region, Journal of Quantitative Spectroscopy and Radiative Transfer, Volume 324, 2024, 109055, https://doi.org/10.1016/j.jqsrt.2024.109055.