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A decade of GOSAT Proxy satellite CH₄ observations

Parker, Robert J. and Webb, Alex and Boesch, Hartmut and Somkuti, Peter and Barrio Guillo, Rocio and Di Noia, Antonio and Kalaitzi, Nikoleta and Anand, Jasdeep S. and Bergamaschi, Peter and Chevallier, Frederic and Palmer, Paul I. and Feng, Liang and Deutscher, Nicholas M. and Feist, Dietrich G. and Griffith, David W. T. and Hase, Frank and Kivi, Rigel and Morino, Isamu and Notholt, Justus and Oh, Young-Suk and Ohyama, Hirofumi and Petri, Christof and Pollard, David F. and Roehl, Coleen and Sha, Mahesh K. and Shiomi, Kei and Strong, Kimberly and Sussmann, Ralf and Té, Yao and Velazco, Voltaire A. and Warneke, Thorsten and Wennberg, Paul O. and Wunch, Debra (2020) A decade of GOSAT Proxy satellite CH₄ observations. Earth System Science Data, 12 (4). pp. 3383-3412. ISSN 1866-3516.

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This work presents the latest release (v9.0) of the University of Leicester GOSAT Proxy XCH₄ dataset. Since the launch of the GOSAT satellite in 2009, these data have been produced by the UK National Centre for Earth Observation (NCEO) as part of the ESA Greenhouse Gas Climate Change Initiative (GHG-CCI) and Copernicus Climate Change Services (C3S) projects. With now over a decade of observations, we outline the many scientific studies achieved using past versions of these data in order to highlight how this latest version may be used in the future. We describe in detail how the data are generated, providing information and statistics for the entire processing chain from the L1B spectral data through to the final quality-filtered column-averaged dry-air mole fraction (XCH₄) data. We show that out of the 19.5 million observations made between April 2009 and December 2019, we determine that 7.3 million of these are sufficiently cloud-free (37.6 %) to process further and ultimately obtain 4.6 million (23.5 %) high-quality XCH₄ observations. We separate these totals by observation mode (land and ocean sun glint) and by month, to provide data users with the expected data coverage, including highlighting periods with reduced observations due to instrumental issues. We perform extensive validation of the data against the Total Carbon Column Observing Network (TCCON), comparing to ground-based observations at 22 locations worldwide. We find excellent agreement with TCCON, with an overall correlation coefficient of 0.92 for the 88 345 co-located measurements. The single-measurement precision is found to be 13.72 ppb, and an overall global bias of 9.06 ppb is determined and removed from the Proxy XCH₄ data. Additionally, we validate the separate components of the Proxy (namely the modelled XCO₂ and the XCH₄∕XCO₂ ratio) and find these to be in excellent agreement with TCCON. In order to show the utility of the data for future studies, we compare against simulated XCH₄ from the TM5 model. We find a high degree of consistency between the model and observations throughout both space and time. When focusing on specific regions, we find average differences ranging from just 3.9 to 15.4 ppb. We find the phase and magnitude of the seasonal cycle to be in excellent agreement, with an average correlation coefficient of 0.93 and a mean seasonal cycle amplitude difference across all regions of −0.84 ppb. These data are available at (Parker and Boesch, 2020).

Item Type:Article
Related URLs:
URLURL TypeDescription ItemData ItemTCCON Data Archive!/dataset/cams-global-greenhouse-gas-inversionRelated ItemCAMS model CO2 (v18r2) ItemMACC model CH4 (v10-S1NOAA) ItemNOAA CarbonTracker model CO2 (CT2017 and CT2019-NRT)
Parker, Robert J.0000-0002-0801-0831
Webb, Alex0000-0002-7164-7835
Boesch, Hartmut0000-0003-3944-9879
Somkuti, Peter0000-0002-5858-8471
Di Noia, Antonio0000-0002-5052-0763
Bergamaschi, Peter0000-0003-4555-1829
Chevallier, Frederic0000-0002-4327-3813
Palmer, Paul I.0000-0002-1487-0969
Deutscher, Nicholas M.0000-0002-2906-2577
Feist, Dietrich G.0000-0002-5890-6687
Griffith, David W. T.0000-0002-7986-1924
Kivi, Rigel0000-0001-8828-2759
Morino, Isamu0000-0003-2720-1569
Oh, Young-Suk0000-0001-8010-1597
Ohyama, Hirofumi0000-0003-2109-9874
Petri, Christof0000-0002-7010-5532
Pollard, David F.0000-0001-9923-2984
Roehl, Coleen0000-0001-5383-8462
Sha, Mahesh K.0000-0003-1440-1529
Strong, Kimberly0000-0001-9947-1053
Té, Yao0000-0001-6405-8074
Velazco, Voltaire A.0000-0002-1376-438X
Warneke, Thorsten0000-0001-5185-3415
Wennberg, Paul O.0000-0002-6126-3854
Wunch, Debra0000-0002-4924-0377
Alternate Title:A decade of GOSAT Proxy satellite CH4 observations
Additional Information:© Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Received: 07 May 2020 – Discussion started: 03 Jul 2020 – Revised: 21 Oct 2020 – Accepted: 26 Oct 2020 – Published: 14 Dec 2020. Robert J. Parker, Hartmut Boesch, Alex Webb, Paul I. Palmer and Liang Feng are funded via the UK National Centre for Earth Observation (NE/R016518/1 and NE/N018079/1). Rocio Barrio Guillo and Nikoleta Kalaitzi were funded by a Leicester Institute for Space and EO (LISEO) and ESA-Dragon Programme studentship respectively. JSA was funded by an ESA Living Planet Fellowship. We acknowledge funding from the ESA GHG-CCI and Copernicus C3S projects. We thank the Japanese Aerospace Exploration Agency, National Institute for Environmental Studies and the Ministry of Environment for the GOSAT data and their continuous support as part of the Joint Research Agreement. This research used the ALICE High Performance Computing Facility at the University of Leicester for the GOSAT retrievals and analysis. The TM5-4DVAR CH₄ inversions have been supported by ECMWF providing computing resources under the special project “Improve European and global CH₄ and N₂O flux inversions (2018–2020)”. TCCON gratefully acknowledges financial support by ESA within the S5P validation programme. Stations at Park Falls, Lamont and Darwin are supported by NASA. Stations at Tsukuba, Rikubetsu and Burgos are supported in part by the GOSAT series project. Burgos is supported in part by the Energy Development Corp. Philippines. Ascension Island and Garmisch stations have been supported by the European Space Agency (ESA) under grant 4000120088/17/I-EF and by the German Bundesministerium für Wirtschaft und Energie (BMWi) under grants 50EE1711C, 50EE1711E and 50EE1711D. We thank the ESA Ariane Tracking Station at North East Bay, Ascension Island, for hosting and local support. The ETL station is funded by CFI/ORF, NSERC, ECCC and the CSA. The Paris station has received funding from Sorbonne Université, the French research center CNRS, the French space agency CNES and Région Île-de-France. The Eureka measurements were made at the Polar Environment Atmospheric Research Laboratory (PEARL) by the Canadian Network for the Detection of Atmospheric Change (CANDAC), primarily supported by the Natural Sciences and Engineering Research Council of Canada, Environment and Climate Change Canada, and the Canadian Space Agency. The Anmyeondo station has received funding from the Korea Meteorological Administration Research and Development Program ”Development and Assessment of IPCC AR6 Climate Change Scenario” under grant 1365003000. The Réunion station is operated by the Royal Belgian Institute for Space Aeronomy with financial support in 2014, 2015, 2016, 2017, 2018 and 2019 under the EU project ICOS-Inwire and the ministerial decree for ICOS (FR/35/IC4) and local activities supported by LACy/UMR8105 – Université de La Réunion. TCCON measurements in Australia are supported by NASA grants NAG5-12247 and NNH05-GD07G, Australian Research Council grants LE0668470, DP089468, DP110103118, DP140101552, DP160101598 and FT180100327, and the GOSAT series project. This research has been supported by the NERC National Centre for Earth Observation (grant nos. NE/N018079/1 and NE/R016518/1). Author contributions. RJP developed and produced the Proxy XCH4 data, performed the analysis, and wrote the manuscript. AW assisted in the production of the data. AW, PS, ADN, HB, JSA, RBG and NK all contributed to development and analysis at different stages of the processing chain. All authors contributed towards discussion and interpretation of the analysis. PB, FC, PIP and LF provided model data and contributed to the interpretation of the comparisons. All TCCON co-authors provided TCCON data and contributed towards interpretation of the GOSAT–TCCON comparisons. Data availability. The University of Leicester GOSAT Proxy v9.0 XCH4 data are available from the Centre for Environmental Data Analysis data repository at (Parker and Boesch, 2020). The TCCON data are available from the TCCON Data Archive at (TCCON Data Archive, 2020; individual data citations are provided in Table F1). CAMS model CO2 (v18r2) data is available from the Copernicus Atmospheric Data Store at!/dataset/cams-global-greenhouse-gas-inversion (ECMWF, 2020a). MACC model CH4 (v10-S1NOAA) is available from ECMWF at (ECMWF, 2020b). NOAA CarbonTracker model CO2 (CT2017 and CT2019-NRT) are available from NOAA ESRL, Boulder, Colorado, USA, at (NOAA, 2020). The authors declare that they have no conflict of interest. Review statement. This paper was edited by David Carlson and reviewed by three anonymous referees.
Funding AgencyGrant Number
Natural Environment Research Council (NERC)NE/R016518/1
Natural Environment Research Council (NERC)NE/N018079/1
Leicester Institute for Space and EOUNSPECIFIED
European Space Agency (ESA)4000120088/17/I-EF
Japan Aerospace Exploration Agency (JAXA)UNSPECIFIED
National Institute for Environmental Studies (Japan)UNSPECIFIED
Ministry of Environment (Japan)UNSPECIFIED
European Centre for Medium-Range Weather Forecasts (ECMWF)UNSPECIFIED
Energy Development Corp.UNSPECIFIED
Bundesministerium für Wirtschaft und Energie (BMWi)50EE1711C
Bundesministerium für Wirtschaft und Energie (BMWi)50EE1711E
Bundesministerium für Wirtschaft und Energie (BMWi)50EE1711D
Canada Foundation for InnovationUNSPECIFIED
Natural Sciences and Engineering Research Council of Canada (NSERC)UNSPECIFIED
Ontario Research FundUNSPECIFIED
Environment and Climate Change CanadaUNSPECIFIED
Canadian Space Agency (CSA)UNSPECIFIED
Sorbonne UniversitéUNSPECIFIED
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
Centre National d'Études Spatiales (CNES)UNSPECIFIED
Région Île-de-FranceUNSPECIFIED
Korea Meteorological Administration1365003000
Royal Belgian Institute for Space AeronomyUNSPECIFIED
European Research Council (ERC)UNSPECIFIED
ICOS BelgiumFR/35/IC4
Université de La RéunionLACy/UMR8105
Australian Research CouncilLE0668470
Australian Research CouncilDP089468
Australian Research CouncilDP110103118
Australian Research CouncilDP140101552
Australian Research CouncilDP160101598
Australian Research CouncilFT180100327
Issue or Number:4
Record Number:CaltechAUTHORS:20210122-092204711
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Official Citation:Parker, R. J., Webb, A., Boesch, H., Somkuti, P., Barrio Guillo, R., Di Noia, A., Kalaitzi, N., Anand, J. S., Bergamaschi, P., Chevallier, F., Palmer, P. I., Feng, L., Deutscher, N. M., Feist, D. G., Griffith, D. W. T., Hase, F., Kivi, R., Morino, I., Notholt, J., Oh, Y.-S., Ohyama, H., Petri, C., Pollard, D. F., Roehl, C., Sha, M. K., Shiomi, K., Strong, K., Sussmann, R., Té, Y., Velazco, V. A., Warneke, T., Wennberg, P. O., and Wunch, D.: A decade of GOSAT Proxy satellite CH4 observations, Earth Syst. Sci. Data, 12, 3383–3412,, 2020.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:107659
Deposited By: George Porter
Deposited On:22 Jan 2021 20:27
Last Modified:22 Jan 2021 20:27

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