edu.ucar.opensky::articles:26318 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-24T19:32:45.457858 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7pr80zh https://doi.org/10.6084/m9.figshare.c.6617700 https Related Dataset #1 Supplementary material from "Comparison between ozone column depths and methane lifetimes computed by one- and three-dimensional models at different atmospheric O₂ levels" https://doi.org/10.5281/zenodo.7821813 https Related JournalArticle #1 Comparison Between Ozone Column Depths and Methane Lifetimes Computed by 1-D and 3-D Models at Different Atmospheric O₂ Levels Comparison between ozone column depths and methane lifetimes computed by one- and three-dimensional models at different atmospheric O2 levels 2023-05-03T00:00:00Z publication https://n2t.org/ark:/85065/d7pr80zh https://doi.org/10.1098/rsos.230056 Ji, A. author Kasting, J. author Cooke, G. author Marsh, Daniel author Tsigaridis, K. author UCAR/NCAR - Library publisher Recently, Cooke et al. (Cooke et al. 2022 R. Soc. Open Sci. 9, 211165. ()) used a three-dimensional coupled chemistry-climate model (WACCM6) to calculate ozone column depths at varied atmospheric O-2 levels. They argued that previous one-dimensional (1-D) photochemical model studies, e.g. Segura et al. (Segura et al. 2003 Astrobiology 3, 689-708. ()), may have overestimated the ozone column depth at low pO(2), and hence also overestimated the lifetime of methane. We have compared new simulations from an updated version of the Segura et al. model with those from WACCM6, together with some results from a second three-dimensional model. The discrepancy in ozone column depths is probably due to multiple interacting parameters, including H2O in the upper troposphere, lower boundary conditions, vertical and meridional transport rates, and different chemical mechanisms, especially the treatment of O-2 photolysis in the Schumann-Runge (SR) bands (175-205 nm). The discrepancy in tropospheric OH concentrations and methane lifetime between WACCM6 and the 1-D model at low pO(2) is reduced when absorption from CO2 and H2O in this wavelength region is included in WACCM6. Including scattering in the SR bands may further reduce this difference. Resolving these issues can be accomplished by developing an accurate parametrization for O-2 photolysis in the SR bands and then repeating these calculations in the various models. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. None eng geoscientificInformation