{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T03:52:51Z","timestamp":1785901971940,"version":"3.56.0"},"reference-count":41,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2017,11,11]],"date-time":"2017-11-11T00:00:00Z","timestamp":1510358400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The Greenhouse gases Observing SATellite (GOSAT) launched in January 2009 has provided radiance spectra with a Fourier Transform Spectrometer for more than eight years. The Orbiting Carbon Observatory 2 (OCO-2) launched in July 2014, collects radiance spectra using an imaging grating spectrometer. Both sensors observe sunlight reflected from Earth\u2019s surface and retrieve atmospheric carbon dioxide (CO2) concentrations, but use different spectrometer technologies, observing geometries, and ground track repeat cycles. To demonstrate the effectiveness of satellite remote sensing for CO2 monitoring, the GOSAT and OCO-2 teams have worked together pre- and post-launch to cross-calibrate the instruments and cross-validate their retrieval algorithms and products. In this work, we first compare observed radiance spectra within three narrow bands centered at 0.76, 1.60 and 2.06 \u00b5m, at temporally coincident and spatially collocated points from September 2014 to March 2017. We reconciled the differences in observation footprints size, viewing geometry and associated differences in surface bidirectional reflectance distribution function (BRDF). We conclude that the spectral radiances measured by the two instruments agree within 5% for all bands. Second, we estimated mean bias and standard deviation of column-averaged CO2 dry air mole fraction (XCO2) retrieved from GOSAT and OCO-2 from September 2014 to May 2016. GOSAT retrievals used Build 7.3 (V7.3) of the Atmospheric CO2 Observations from Space (ACOS) algorithm while OCO-2 retrievals used Version 7 of the OCO-2 retrieval algorithm. The mean biases and standard deviations are \u22120.57 \u00b1 3.33 ppm over land with high gain, \u22120.17 \u00b1 1.48 ppm over ocean with high gain and \u22120.19 \u00b1 2.79 ppm over land with medium gain. Finally, our study is complemented with an analysis of error sources: retrieved surface pressure (Psurf), aerosol optical depth (AOD), BRDF and surface albedo inhomogeneity. We found no change in XCO2 bias or standard deviation with time, demonstrating that both instruments are well calibrated.<\/jats:p>","DOI":"10.3390\/rs9111158","type":"journal-article","created":{"date-parts":[[2017,11,13]],"date-time":"2017-11-13T11:12:36Z","timestamp":1510571556000},"page":"1158","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["The Cross-Calibration of Spectral Radiances and Cross-Validation of CO2 Estimates from GOSAT and OCO-2"],"prefix":"10.3390","volume":"9","author":[{"given":"Fumie","family":"Kataoka","sequence":"first","affiliation":[{"name":"Remote Sensing Technology Center of Japan, 2-1-1 Sengen, Tsukuba 305-8505, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4573-9998","authenticated-orcid":false,"given":"David","family":"Crisp","sequence":"additional","affiliation":[{"name":"Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Taylor","sequence":"additional","affiliation":[{"name":"Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, CO 80523, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chris","family":"O\u2019Dell","sequence":"additional","affiliation":[{"name":"Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, CO 80523, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5415-3377","authenticated-orcid":false,"given":"Akihiko","family":"Kuze","sequence":"additional","affiliation":[{"name":"Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba 305-8505, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kei","family":"Shiomi","sequence":"additional","affiliation":[{"name":"Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba 305-8505, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroshi","family":"Suto","sequence":"additional","affiliation":[{"name":"Japan Aerospace Exploration Agency, 2-1-1 Sengen, Tsukuba 305-8505, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carol","family":"Bruegge","sequence":"additional","affiliation":[{"name":"Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Florian","family":"Schwandner","sequence":"additional","affiliation":[{"name":"Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109, USA"},{"name":"Joint Institute for Regional Earth System Science and Engineering (JIFRESSE), University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Rosenberg","sequence":"additional","affiliation":[{"name":"Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lars","family":"Chapsky","sequence":"additional","affiliation":[{"name":"Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard","family":"Lee","sequence":"additional","affiliation":[{"name":"Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,11,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2447","DOI":"10.5194\/amt-5-2447-2012","article-title":"Level 1 algorithms for TANSO on GOSAT: Processing and on-orbit calibration","volume":"5","author":"Kuze","year":"2012","journal-title":"Atmos. Meas. Tech."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Zhang, L.L., Yue, T.X., Wilson, J.P., Wang, D.Y., Zhao, N., Liu, Y., Liu, D.D., Du, Z.P., Wang, Y.F., and Lin, C. (2016). Modelling of XCO2 Surfaces Based on Flight Tests of TanSat. Sensors, 16.","DOI":"10.3390\/s16111818"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1016\/j.rse.2011.09.027","article-title":"TROPOMI on the ESA Sentinel-5 precursor: A GMES mission for global observations of the atmospheric composition for climate, air quality and ozone layer applications, the Sentinel missions \u2013 new opportunities for science","volume":"120","author":"Veefkind","year":"2012","journal-title":"Remote Sens. Environ."},{"key":"ref_4","unstructured":"Suto, H., Kuze, A., Shiomi, K., and Nakajima, M. (2013, January 9\u201313). Space-based carbon monitoring by GOSAT and GOSAT-2: Lessons learned from GOSAT in-orbit operation and towards better accuracy of XCO2 observation. Proceedings of the AGU fall meeting, San Francisco, CA, USA."},{"key":"ref_5","unstructured":"(2017, August 22). Orbiting Carbon Observatory-3 (OCO-3) Project Web Site, Available online: https:\/\/oco3.jpl.nasa.gov\/."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"344","DOI":"10.1016\/j.rse.2013.04.024","article-title":"The Greenhouse Gas Climate Change Initiative (GHG-CCI): Comparison and quality assessment of near-surface-sensitive satellite-derived CO2 and CH4 global data sets","volume":"162","author":"Buchwitz","year":"2015","journal-title":"Remote Sens. Environ."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2961","DOI":"10.5194\/amt-8-2961-2015","article-title":"Consistent satellite XCO2 retrievals for SCIAMACHY and GOSAT using the BESD algorithm","volume":"8","author":"Heymann","year":"2015","journal-title":"Atmos. Meas. Tech."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"6716","DOI":"10.1364\/AO.48.006716","article-title":"Thermal and near infrared sensor for carbon observation Fourier-transform spectrometer on the Greenhouse Gases Observing Satellite for greenhouse gases monitoring","volume":"48","author":"Kuze","year":"2009","journal-title":"Appl. Opt."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"939","DOI":"10.5194\/amt-10-939-2017","article-title":"Characterization of the OCO-2 instrument line shape functions using on-orbit solar measurements","volume":"10","author":"Sun","year":"2017","journal-title":"Atmos. Meas. Tech."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"59","DOI":"10.5194\/amt-10-59-2017","article-title":"The on-orbit performance of the Orbiting Carbon Observatory-2 (OCO-2) instrument and its radiometrically calibrated products","volume":"10","author":"Crisp","year":"2017","journal-title":"Atmos. Meas. Tech."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1994","DOI":"10.1109\/TGRS.2016.2634023","article-title":"Preflight Radiometric Calibration of Orbiting Carbon Observatory 2","volume":"5","author":"Rosenberg","year":"2017","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2499","DOI":"10.1109\/TGRS.2016.2645614","article-title":"Preflight Spectral Calibration of Orbiting Carbon Observatory 2","volume":"5","author":"Lee","year":"2017","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"585","DOI":"10.1109\/TGRS.2009.2026050","article-title":"OCO-GOSAT preflight cross calibration experiment","volume":"48","author":"Sakuma","year":"2010","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"3991","DOI":"10.1109\/TGRS.2013.2278696","article-title":"Long-term vicarious calibration of GOSAT short-wave sensors: Techniques for error reduction and new estimates of radiometric degradation factors","volume":"52","author":"Kuze","year":"2014","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_15","unstructured":"(2017, August 04). Institute for Environmental Studies (NIES) GOSAT Data Archive Service (GDAS). Available online: https:\/\/data2.gosat.nies.go.jp\/."},{"key":"ref_16","unstructured":"(2017, August 14). NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) Web Site, Available online: https:\/\/oco2.gesdisc.eosdis.nasa.gov\/data\/."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2445","DOI":"10.5194\/amt-9-2445-2016","article-title":"Update on GOSAT TANSO-FTS performance, operations, and data products after more than six years in space","volume":"9","author":"Kuze","year":"2016","journal-title":"Atmos. Meas. Tech."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1781","DOI":"10.1109\/TGRS.2010.2089527","article-title":"Vicarious Calibration of the GOSAT Sensors Using the Railroad Valley Desert Playa","volume":"49","author":"Kuze","year":"2011","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"4969","DOI":"10.1364\/AO.52.004969","article-title":"Characterization and correction of spectral distortions induced by microvibrations onboard the GOSAT Fourier transform spectrometer","volume":"52","author":"Suto","year":"2013","journal-title":"Appl. Opt."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"549","DOI":"10.5194\/amt-10-549-2017","article-title":"The Orbiting Carbon Observatory-2: First 18 months of science data products","volume":"10","author":"Eldering","year":"2017","journal-title":"Atmos. Meas. Tech."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"99","DOI":"10.5194\/amt-5-99-2012","article-title":"The ACOS CO2 retrieval algorithm\u2014Part 1: Description and validation against synthetic observations","volume":"5","author":"Connor","year":"2012","journal-title":"Atmos. Meas. Tech."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"687","DOI":"10.5194\/amt-5-687-2012","article-title":"The ACOS XCO2 retrieval algorithm, Part 2: Global XCO2 data characterization","volume":"5","author":"Crisp","year":"2012","journal-title":"Atmos. Meas. Tech."},{"key":"ref_23","unstructured":"Osterman, G., Eldering, A., Cheng, C., O\u2019Dell, C., Crisp, D., Frankenberg, C., and Fisher, B. (2017, August 03). ACOS Level 2 Standard Product and Lite Data Product Data User\u2019s Guide, v7.3, Available online: https:\/\/docserver.gesdisc.eosdis.nasa.gov\/public\/project\/OCO\/ACOS%20v7.3_DataUsersGuide-RevE.pdf."},{"key":"ref_24","unstructured":"B\u00f6sch, H., Brown, L., Castano, R., Christi, M., Connor, B., Crisp, D., Eldering, A., Fisher, B., Frankenberg, C., and Gunson, M. (2017, October 06). Orbiting Carbon Observatory (OCO)-2 Level 2 Full Physics Retrieval Algorithm Theoretical Basis Document, Available online: https:\/\/docserver.gesdisc.eosdis.nasa.gov\/public\/project\/OCO\/OCO2_L2_ATBD.V6.pdf."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"26497","DOI":"10.1029\/1999JD900745","article-title":"Ground-based observations of Arctic O3 loss during spring and summer 1997","volume":"104","author":"Toon","year":"1999","journal-title":"J. Geophys. Res."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1023\/A:1024048429145","article-title":"The Solar Spectral Irradiance from 200 to 2400 nm as Measured by the SOLSPEC Spectrometer from the Atlas and Eureca Missions","volume":"214","author":"Thuillier","year":"2003","journal-title":"Solar Phys."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"12317","DOI":"10.5194\/acp-11-12317-2011","article-title":"A method for evaluating bias in global measurements of CO2 total columns from space","volume":"11","author":"Wunch","year":"2011","journal-title":"Atmos. Chem. Phys."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"13023","DOI":"10.5194\/acp-15-13023-2015","article-title":"Does GOSAT capture the true seasonal cycle of carbon dioxide?","volume":"15","author":"Lindqvist","year":"2015","journal-title":"Atmos. Chem. Phys."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"683","DOI":"10.5194\/amt-9-683-2016","article-title":"Consistent evaluation of ACOS-GOSAT, BESD-SCIAMACHY, CarbonTracker, and MACC through comparisons to TCCON","volume":"9","author":"Kulawik","year":"2016","journal-title":"Atmos. Meas. Tech."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"2209","DOI":"10.5194\/amt-10-2209-2017","article-title":"Comparisons of the Orbiting Carbon Observatory-2 (OCO-2) XCO2 measurements with TCCON","volume":"10","author":"Wunch","year":"2017","journal-title":"Atmos. Meas. Tech."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Taylor1, E.T., O\u2019Dell1, W.C., Frankenberg, C., Partain, T.P., Cronk, Q.H., Savtchenko, A., Nelson, N.R., Rosenthal, J.E., Chang, Y.A., and Fisher, B. (2016). Orbiting Carbon Observatory-2 (OCO-2) cloud screening algorithms: Validation against collocated MODIS and CALIOP data. Atmos. Meas. Tech., 9, 973\u2013989.","DOI":"10.5194\/amt-9-973-2016"},{"key":"ref_32","unstructured":"(2017, August 14). MODIS BRDF-Albedo Model Parameters 16-Day L3 Global 1km (MCD43B1), Available online: https:\/\/lpdaac.usgs.gov\/dataset_discovery\/modis\/modis_products_table\/mcd43b1."},{"key":"ref_33","unstructured":"Strahler, A.H., and Muller, J.-P. (2017, November 10). Available online: http:\/\/citeseerx.ist.psu.edu\/viewdoc\/download?doi=10.1.1.133.7683&rep=rep1&type=pdf."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"5199","DOI":"10.1109\/TGRS.2012.2232673","article-title":"Testing the polarization model for TANSO-FTS on GOSAT against clear-sky observations of sun-glint over ocean","volume":"51","author":"Polonsky","year":"2013","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"13129","DOI":"10.1002\/2015JD024720","article-title":"An advanced retrieval algorithm for greenhouse gases using polarization information measured by GOSAT TANSO-FTS SWIR I: Simulation study","volume":"121","author":"Kikuchi","year":"2016","journal-title":"J. Geophys. Res."},{"key":"ref_36","unstructured":"(2017, November 10). OCO-2 Warn Level, Bias Correction, and Lite File Product Description, Available online: https:\/\/co2.jpl.nasa.gov\/static\/docs\/OCO2_XCO2_Lite_Files_and_Bias_Correction_0716.docx."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"L03801","DOI":"10.1029\/2010GL045896","article-title":"Disentangling chlorophyll fluorescence from atmospheric scattering effects in O2 A-band spectra of reflected sun-light","volume":"38","author":"Frankenberg","year":"2011","journal-title":"Geophys. Res. Lett."},{"key":"ref_38","unstructured":"(2017, August 14). NASA AERONET (AErosol RObotic NETwork) Program Web Site, Available online: https:\/\/aeronet.gsfc.nasa.gov\/."},{"key":"ref_39","first-page":"D01106","article-title":"Validation of Moderate Resolution Imaging Spectroradiometer (MODIS) albedo retrieval algorithm: Dependence of albedo on solar zenith angle","volume":"114","author":"Jicheng","year":"2009","journal-title":"J. Geophys. Res."},{"key":"ref_40","first-page":"D10314","article-title":"Precision requirements for space-based XCO2 data","volume":"112","author":"Miller","year":"2007","journal-title":"J. Geophys. Res."},{"key":"ref_41","unstructured":"Shiomi, K., Kuze, A., Hashimoto, M., Suto, H., Kataoka, F., Igarashi, T., and Kawakami, S. (2017, January 3\u20139). Calibration and validation activities for GOSAT collaborated with OCO-2. Proceedings of the 31st International Symposium on Space Technology and Science, Matsuyama, Japan."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/11\/1158\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:49:04Z","timestamp":1760208544000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/11\/1158"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,11,11]]},"references-count":41,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2017,11]]}},"alternative-id":["rs9111158"],"URL":"https:\/\/doi.org\/10.3390\/rs9111158","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,11,11]]}}}