Absorption Coefficient (ABSCO) Tables for the Orbiting Carbon Observatories: Version 5.1
Abstract
The accuracy of atmospheric trace gas retrievals depends directly on the accuracy of the molecular absorption model used within the retrieval algorithm. For remote sensing of well-mixed gases, such as carbon dioxide (CO₂), where the atmospheric variability is small compared to the background, the quality of the molecular absorption model is key. Recent updates to oxygen (O₂) absorption coefficients (ABSCO) for the 0.76 μm A-band and the water vapor (H₂O) continuum model within the 1.6 μm and 2.06 μm CO₂ bands used within the Orbiting Carbon Observatory (OCO-2 and OCO-3) algorithm are described here. Updates in the O₂ A-band involve the inclusion of new laboratory measurements within multispectrum fits to improve relative consistency between O₂ line shapes and collision-induced absorption (CIA). The H₂O continuum model has been updated to MTCKD v3.2, which has benefited from information from a range of laboratory studies relative to the model utilized in the previous ABSCO version. Impacts of these spectroscopy updates have been evaluated against ground-based atmospheric spectra from the Total Carbon Column Observing Network (TCCON) and within the framework of the OCO-2 algorithm, using OCO-2 soundings covering a range of atmospheric and surface conditions. The updated absorption coefficients (ABSCO version 5.1) are found to offer improved fitting residuals and reduced biases in retrieved surface pressure relative to the previous version (ABSCO v5.0) used within B8 and B9 of the OCO-2 retrieval algorithm and have been adopted for the OCO B10 Level 2 algorithm.
Additional Information
© 2020 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license. (http://creativecommons.org/licenses/by/4.0/). Received 14 April 2020, Revised 13 July 2020, Accepted 13 July 2020, Available online 6 August 2020. Portions of the research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. The authors gratefully acknowledge financial support from the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research, Environmental Sciences Division, as part of the ARM program under Grant DEFG02-90ER610. Support was also provided by the National Institute of Standards and Technology (NIST) Greenhouse Gas Measurements and Climate Research Program and the Orbiting Carbon Observatory (OCO) projects, National Aeronautics and Space Administration (NASA) Earth System Science Pathfinder (ESSP) missions. Manufacturers and product names are listed solely for completeness. These specific citations neither constitute an endorsement of the products nor imply that similar products from other companies would be less suitable. Copyright 2020 California Institute of Technology. Government sponsorship acknowledged.Errata
Vivienne H. Payne, Brian J. Drouin, Fabiano Oyafuso, Le Kuai, Brendan M. Fisher, Keeyoon Sung, Deacon Nemchick, Timothy J. Crawford, Mike Smyth, David Crisp, Erin Adkins, Joseph T. Hodges, David A. Long, Eli J. Mlawer, Aronne Merrelli, Elizabeth Lunny, Christopher W. O'Dell, Corrigendum to "Absorption Coefficient (ABSCO) Tables for the Orbiting Carbon Observatories: Version 5.1" [J. Quant. Spectrosc. Radiat. Transf. 255 (2020) 107217], Journal of Quantitative Spectroscopy and Radiative Transfer, 2020, 107333, ISSN 0022-4073, https://doi.org/10.1016/j.jqsrt.2020.107333. (http://www.sciencedirect.com/science/article/pii/S0022407320308001)Attached Files
Published - 1-s2.0-S0022407320302016-main.pdf
Supplemental Material - 1-s2.0-S0022407320302016-mmc1.xml
Supplemental Material - 1-s2.0-S0022407320302016-mmc2.pdf
Erratum - 1-s2.0-S0022407320308001-main.pdf
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Additional details
- Eprint ID
- 104813
- Resolver ID
- CaltechAUTHORS:20200807-090348283
- NASA/JPL/Caltech
- DE-FG02-90ER610
- Department of Energy (DOE)
- National Institute of Standards and Technology (NIST)
- Created
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2020-08-10Created from EPrint's datestamp field
- Updated
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2023-06-01Created from EPrint's last_modified field