High accuracy absorption coefficients for the Orbiting Carbon Observatory-2 (OCO-2) mission: Validation of updated carbon dioxide cross-sections using atmospheric spectra

Oyafuso, Fabiano; Payne, Vivienne H.; Drouin, Brian J.; Devi, V. Malathy; Benner, D. Chris; Sung, Keeyoon; Yu, Shanshan; Gordon, Iouli E.; Kochanov, Roman V.; Tan, Yan; Crisp, David; Mlawer, E. J.; Guillaume, Alexandre

doi:10.1016/j.jqsrt.2017.06.012

Cited by 40 publications

(40 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There was about a 4% unexplained systematic offset between the measurements of Delahaye et al (2016a) and those of Sung et al (2009) in the same spectral region of 4.3 μm, although they were sharing the same rotational dependence. Sung et al (2009) data are used for spectroscopic input for the OCO-2 mission (Oyafuso et al, 2017), and therefore for consistency, the experimental results converted from (Delahaye et al, 2016a) were then divided by 0.96 before fitting. In order to make more accurate predictions for transitions involving high-rotational quanta, the calculated half-widths from were also incorporated into the fitting (only for 63 ≤ | m | ≤ 101 and m = 121) but were multiplied by a factor of 0.975 derived here to account for discrepancy between these calculations and measurements from Sung et al (2009).…”

Section: Comentioning

confidence: 99%

Introduction of Water‐Vapor Broadening Parameters and Their Temperature‐Dependent Exponents Into the HITRAN Database: Part I—CO₂, N₂O, CO, CH₄, O₂, NH₃, and H₂S

et al. 2019

View full text Add to dashboard Cite

The amount of water vapor in the terrestrial atmosphere is highly variable both spatially and temporally. In the tropics it sometimes constitutes 4–5% of the atmosphere. At the same time collisional broadening of spectral lines by water vapor is much larger than that by nitrogen and oxygen. Therefore, in order to accurately characterize and model spectra of the atmospheres with significant amounts of water vapor, the line‐shape parameters for spectral lines broadened by water vapor are required. In this work, the pressure‐broadening parameters (and their temperature‐dependent exponents) due to the pressure of water vapor for spectral lines of CO2, N2O, CO, CH4, O2, NH3, and H2S from both experimental and theoretical studies were collected and carefully reviewed. A set of semiempirical models based on these collected data was proposed and then used to estimate water broadening and its temperature dependence for all transitions of selected molecules in the HITRAN2016 database.

show abstract

Section: Comentioning

confidence: 99%

Introduction of Water‐Vapor Broadening Parameters and Their Temperature‐Dependent Exponents Into the HITRAN Database: Part I—CO₂, N₂O, CO, CH₄, O₂, NH₃, and H₂S

et al. 2019

View full text Add to dashboard Cite

show abstract

“…[578]. These applications have concentration retrieval targets with uncertainties at the 0.25 % level or below and therefore motivate low-uncertainty laboratory measurements that incorporate advanced line profiles (eg [9,100,689] and references therein ; see also Sec. 5.1.1a).…”

Section: Accepted Manuscriptmentioning

confidence: 99%

Recent advances in collisional effects on spectra of molecular gases and their practical consequences

Hartmann

Tran

Armante

et al. 2018

Journal of Quantitative Spectroscopy and Radiative Transfer

100

View full text Add to dashboard Cite

“…Successive versions of these tables have been refined by incorporating new laboratory results and theoret-5 ical models for increasingly accurate absorption coefficients. The ABSCO version used in the B8 algorithm is ABSCO v5.0 Oyafuso et al, 2017).…”

Section: Spectroscopy-related Changesmentioning

confidence: 99%

“…This additional absorption was parameterized in order to reduce errors in retrievals with TCCON up-looking spectra. Further details can be found in and Oyafuso et al (2017).…”

Section: Spectroscopy-related Changesmentioning

confidence: 99%

“…For the 1.61 µm band, the ABSCO v5.0 tables include a uniform scaling to bring the intensities from the Devi et al (2016) multispectrum fit into line with reference intensity measurements (estimated accuracy 10 ∼0.2 %) from Polyansky et al (2015). Oyafuso et al (2017) show that this pre-scaling of the ABSCO using reference lab- oratory measurements results in good consistency between single-band up-looking X CO2 retrievals from ground-based FTS spectra and the X CO2 values reported by TCCON (which are themselves calibrated to agree with reference airborne profiles).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Improved Retrievals of Carbon Dioxide from the Orbiting Carbon Observatory-2 with the version 8 ACOS algorithm

O’Dell¹,

Eldering²,

Wennberg³

et al. 2018

Preprint

Self Cite

View full text Add to dashboard Cite

Abstract. Since September 2014, NASA's Orbiting Carbon Observatory-2 (OCO-2) satellite has been taking measurements of reflected solar spectra and using them to infer atmospheric carbon dioxide levels. This work provides details of the OCO-2 retrieval algorithm, versions 7 and 8, used to derive the column-averaged dry air mole fraction of atmospheric CO2,/sub> (XCO2) for the roughly 100,000 cloud-free measurements recorded by OCO-2 each day. The algorithm is based on the Atmospheric Carbon Observations from Space (ACOS) algorithm which has been applied to observations from the Greenhouse Gases Observing SATellite (GOSAT) since 2009, with modifications necessary for OCO-2. Because high accuracy, better than 0.25 %, is required in order to accurately infer carbon sources and sinks from XCO2, significant errors and regional-scale biases in the measurements must be minimized. We discuss efforts to filter out poor quality measurements, and correct the remaining good-quality measurements to minimize regional-scale biases. Updates to the radiance calibration and retrieval forward model in version 8 have improved many aspects of the retrieved data products. The version 8 data appear to have reduced regional-scale biases overall, and demonstrate a clear improvement over the version 7 data. In particular, error variance with respect to TCCON was reduced by 20 % over land and 40 % over ocean between versions 7 and 8, and nadir and glint observations over land are now more consistent. While this paper documents the significant improvements in the ACOS algorithm, it will continue to evolve and improve as the CO2 data record continues to expand.

show abstract

High accuracy absorption coefficients for the Orbiting Carbon Observatory-2 (OCO-2) mission: Validation of updated carbon dioxide cross-sections using atmospheric spectra

Cited by 40 publications

References 54 publications

Introduction of Water‐Vapor Broadening Parameters and Their Temperature‐Dependent Exponents Into the HITRAN Database: Part I—CO₂, N₂O, CO, CH₄, O₂, NH₃, and H₂S

Introduction of Water‐Vapor Broadening Parameters and Their Temperature‐Dependent Exponents Into the HITRAN Database: Part I—CO₂, N₂O, CO, CH₄, O₂, NH₃, and H₂S

Recent advances in collisional effects on spectra of molecular gases and their practical consequences

Improved Retrievals of Carbon Dioxide from the Orbiting Carbon Observatory-2 with the version 8 ACOS algorithm

Contact Info

Product

Resources

About

High accuracy absorption coefficients for the Orbiting Carbon Observatory-2 (OCO-2) mission: Validation of updated carbon dioxide cross-sections using atmospheric spectra

Cited by 40 publications

References 54 publications

Introduction of Water‐Vapor Broadening Parameters and Their Temperature‐Dependent Exponents Into the HITRAN Database: Part I—CO2, N2O, CO, CH4, O2, NH3, and H2S

Introduction of Water‐Vapor Broadening Parameters and Their Temperature‐Dependent Exponents Into the HITRAN Database: Part I—CO2, N2O, CO, CH4, O2, NH3, and H2S

Recent advances in collisional effects on spectra of molecular gases and their practical consequences

Improved Retrievals of Carbon Dioxide from the Orbiting Carbon Observatory-2 with the version 8 ACOS algorithm

Contact Info

Product

Resources

About

Introduction of Water‐Vapor Broadening Parameters and Their Temperature‐Dependent Exponents Into the HITRAN Database: Part I—CO₂, N₂O, CO, CH₄, O₂, NH₃, and H₂S

Introduction of Water‐Vapor Broadening Parameters and Their Temperature‐Dependent Exponents Into the HITRAN Database: Part I—CO₂, N₂O, CO, CH₄, O₂, NH₃, and H₂S