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Title: Improved retrievals of carbon dioxide from Orbiting Carbon Observatory-2 with the version 8 ACOS algorithm

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( X CO 2 ) for the roughly 100000 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 X CO 2 , 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.

Authors:
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  1. Colorado State Univ., Fort Collins, CO (United States)
  2. California Inst. of Technology (CalTech), Pasadena, CA (United States)
  3. Finnish Meteorological Inst., Helsinki (Finland)
  4. Univ. of Wisconsin, Madison, WI (United States)
  5. Univ. of Toronto, ON (Canada)
  6. NOAA Earth System Research Laboratory, Boulder, CO (United States); Univ. of Colorado, Boulder, CO (United States)
  7. CEA-CNRS-UVSQ, Gif-sur-Yvette (France)
  8. Univ. of Oklahoma, Norman, OK (United States)
  9. Univ. of Edinburgh, Scotland (United Kingdom)
  10. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  11. Meteorological State Agency of Spain (AEMet), Santa Cruz de Tenerife (Spain)
  12. Univ. of Wollongong, NSW (Australia)
  13. Karlsruhe Inst. of Technology (Germany)
  14. NASA Ames Research Center, Moffett Field, CA (United States)
  15. Finnish Meteorological Institute, Sodankylä (Finland)
  16. National Inst. for Environmental Studies (NIES), Tsukuba (Japan)
  17. Univ. of Bremen (Germany)
  18. Royal Belgian Institute for Space Aeronomy, Brussels (Belgium)
  19. Sorbonne Université, Observatoire de Paris, Université PSL, CNRS, Paris (France)
Publication Date:
Research Org.:
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC). Biological and Environmental Research (BER) (SC-23)
OSTI Identifier:
1557767
Report Number(s):
LA-UR-19-22771
Journal ID: ISSN 1867-8548
Grant/Contract Number:  
89233218CNA000001
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Atmospheric Measurement Techniques (Online)
Additional Journal Information:
Journal Volume: 11; Journal Issue: 12; Journal ID: ISSN 1867-8548
Publisher:
European Geosciences Union
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; 58 GEOSCIENCES; Earth Sciences; Energy Sciences; Satellite; OCO-2; TCCON; CO2 validation; Carbon Cycle; Climate; Remote Sensing; Amazon

Citation Formats

O'Dell, Christopher W., Eldering, Annmarie, Wennberg, Paul O., Crisp, David, Gunson, Michael R., Fisher, Brendan, Frankenberg, Christian, Kiel, Matthäus, Lindqvist, Hannakaisa, Mandrake, Lukas, Merrelli, Aronne, Natraj, Vijay, Nelson, Robert R., Osterman, Gregory B., Payne, Vivienne H., Taylor, Thomas E., Wunch, Debra, Drouin, Brian J., Oyafuso, Fabiano, Chang, Albert, McDuffie, James, Smyth, Michael, Baker, David F., Basu, Sourish, Chevallier, Frédéric, Crowell, Sean M. R., Feng, Liang, Palmer, Paul I., Dubey, Mavendra Krishna, García, Omaira E., Griffith, David W. T., Hase, Frank, Iraci, Laura T., Kivi, Rigel, Morino, Isamu, Notholt, Justus, Ohyama, Hirofumi, Petri, Christof, Roehl, Coleen M., Sha, Mahesh K., Strong, Kimberly, Sussmann, Ralf, Te, Yao, Uchino, Osamu, and Velazco, Voltaire A. Improved retrievals of carbon dioxide from Orbiting Carbon Observatory-2 with the version 8 ACOS algorithm. United States: N. p., 2018. Web. doi:10.5194/amt-11-6539-2018.
O'Dell, Christopher W., Eldering, Annmarie, Wennberg, Paul O., Crisp, David, Gunson, Michael R., Fisher, Brendan, Frankenberg, Christian, Kiel, Matthäus, Lindqvist, Hannakaisa, Mandrake, Lukas, Merrelli, Aronne, Natraj, Vijay, Nelson, Robert R., Osterman, Gregory B., Payne, Vivienne H., Taylor, Thomas E., Wunch, Debra, Drouin, Brian J., Oyafuso, Fabiano, Chang, Albert, McDuffie, James, Smyth, Michael, Baker, David F., Basu, Sourish, Chevallier, Frédéric, Crowell, Sean M. R., Feng, Liang, Palmer, Paul I., Dubey, Mavendra Krishna, García, Omaira E., Griffith, David W. T., Hase, Frank, Iraci, Laura T., Kivi, Rigel, Morino, Isamu, Notholt, Justus, Ohyama, Hirofumi, Petri, Christof, Roehl, Coleen M., Sha, Mahesh K., Strong, Kimberly, Sussmann, Ralf, Te, Yao, Uchino, Osamu, & Velazco, Voltaire A. Improved retrievals of carbon dioxide from Orbiting Carbon Observatory-2 with the version 8 ACOS algorithm. United States. https://doi.org/10.5194/amt-11-6539-2018
O'Dell, Christopher W., Eldering, Annmarie, Wennberg, Paul O., Crisp, David, Gunson, Michael R., Fisher, Brendan, Frankenberg, Christian, Kiel, Matthäus, Lindqvist, Hannakaisa, Mandrake, Lukas, Merrelli, Aronne, Natraj, Vijay, Nelson, Robert R., Osterman, Gregory B., Payne, Vivienne H., Taylor, Thomas E., Wunch, Debra, Drouin, Brian J., Oyafuso, Fabiano, Chang, Albert, McDuffie, James, Smyth, Michael, Baker, David F., Basu, Sourish, Chevallier, Frédéric, Crowell, Sean M. R., Feng, Liang, Palmer, Paul I., Dubey, Mavendra Krishna, García, Omaira E., Griffith, David W. T., Hase, Frank, Iraci, Laura T., Kivi, Rigel, Morino, Isamu, Notholt, Justus, Ohyama, Hirofumi, Petri, Christof, Roehl, Coleen M., Sha, Mahesh K., Strong, Kimberly, Sussmann, Ralf, Te, Yao, Uchino, Osamu, and Velazco, Voltaire A. 2018. "Improved retrievals of carbon dioxide from Orbiting Carbon Observatory-2 with the version 8 ACOS algorithm". United States. https://doi.org/10.5194/amt-11-6539-2018. https://www.osti.gov/servlets/purl/1557767.
@article{osti_1557767,
title = {Improved retrievals of carbon dioxide from Orbiting Carbon Observatory-2 with the version 8 ACOS algorithm},
author = {O'Dell, Christopher W. and Eldering, Annmarie and Wennberg, Paul O. and Crisp, David and Gunson, Michael R. and Fisher, Brendan and Frankenberg, Christian and Kiel, Matthäus and Lindqvist, Hannakaisa and Mandrake, Lukas and Merrelli, Aronne and Natraj, Vijay and Nelson, Robert R. and Osterman, Gregory B. and Payne, Vivienne H. and Taylor, Thomas E. and Wunch, Debra and Drouin, Brian J. and Oyafuso, Fabiano and Chang, Albert and McDuffie, James and Smyth, Michael and Baker, David F. and Basu, Sourish and Chevallier, Frédéric and Crowell, Sean M. R. and Feng, Liang and Palmer, Paul I. and Dubey, Mavendra Krishna and García, Omaira E. and Griffith, David W. T. and Hase, Frank and Iraci, Laura T. and Kivi, Rigel and Morino, Isamu and Notholt, Justus and Ohyama, Hirofumi and Petri, Christof and Roehl, Coleen M. and Sha, Mahesh K. and Strong, Kimberly and Sussmann, Ralf and Te, Yao and Uchino, Osamu and Velazco, Voltaire A.},
abstractNote = {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(XCO2) for the roughly 100000 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.},
doi = {10.5194/amt-11-6539-2018},
url = {https://www.osti.gov/biblio/1557767}, journal = {Atmospheric Measurement Techniques (Online)},
issn = {1867-8548},
number = 12,
volume = 11,
place = {United States},
year = {Tue Dec 11 00:00:00 EST 2018},
month = {Tue Dec 11 00:00:00 EST 2018}
}

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Works referenced in this record:

Global CO 2 fluxes estimated from GOSAT retrievals of total column CO 2
journal, January 2013


Quantifying CO 2 Emissions From Individual Power Plants From Space
journal, October 2017


Contrasting carbon cycle responses of the tropical continents to the 2015–2016 El Niño
journal, October 2017


A method for colocating satellite X CO 2 data to ground-based data and its application to ACOS-GOSAT and TCCON
journal, January 2014


Uncertainties in atmospheric surface pressure fields from global analyses
journal, January 2008


MERRA: NASA’s Modern-Era Retrospective Analysis for Research and Applications
journal, July 2011


The ACOS CO 2 retrieval algorithm – Part II: Global X CO 2 data characterization
journal, January 2012


Carbon dioxide retrieval from OCO-2 satellite observations using the RemoTeC algorithm and validation with TCCON measurements
journal, January 2018


Line parameters including temperature dependences of air- and self-broadened line shapes of 12C16O2: 2.06-μm region
journal, August 2016


Does GOSAT capture the true seasonal cycle of carbon dioxide?
journal, January 2015


Fourier transform spectrometer measurements of column CO 2 at Sodankylä, Finland
journal, January 2016


Ice cloud single-scattering property models with the full phase matrix at wavelengths from 0.2 to 100µm
journal, October 2014


Orbiting Carbon Observatory-2 (OCO-2) cloud screening algorithms: validation against collocated MODIS and CALIOP data
journal, January 2016


The Orbiting Carbon Observatory-2 early science investigations of regional carbon dioxide fluxes
journal, October 2017


Pressure broadening of oxygen by water
journal, January 2014


Intercomparability of X CO 2 and X CH 4 from the United States TCCON sites
journal, January 2017


TCCON data from Orléans (FR), Release GGG2014.R0
dataset, September 2017


The current status of GOSAT and the concept of GOSAT-2
conference, November 2012


A multispectrum nonlinear least squares fitting technique
journal, June 1995


High-Accuracy CO 2 Line Intensities Determined from Theory and Experiment
journal, June 2015


Line parameters including temperature dependences of self- and air-broadened line shapes of 12C16O2: 1.6-μm region
journal, July 2016


CO 2 surface fluxes at grid point scale estimated from a global 21 year reanalysis of atmospheric measurements
journal, January 2010


The 2015–2016 carbon cycle as seen from OCO-2 and the global in situ network
journal, January 2019


Does GOSAT capture the true seasonal cycle of carbon dioxide
text, January 2015


Measurement of the Roughness of the Sea Surface from Photographs of the Sun’s Glitter
journal, January 1954


The on-orbit performance of the Orbiting Carbon Observatory-2 (OCO-2) instrument and its radiometrically calibrated products
journal, January 2017


The impact of transport model differences on CO 2 surface flux estimates from OCO-2 retrievals of column average CO 2
journal, January 2018


Calibration of the Total Carbon Column Observing Network using aircraft profile data
journal, January 2010


The Orbiting Carbon Observatory-2: first 18 months of science data products
journal, January 2017


Atmospheric validation of high accuracy CO2 absorption coefficients for the OCO-2 mission
journal, November 2012


Using airborne HIAPER Pole-to-Pole Observations (HIPPO) to evaluate model and remote sensing estimates of atmospheric carbon dioxide
journal, January 2016


Development and recent evaluation of the MT_CKD model of continuum absorption
journal, June 2012

  • Mlawer, Eli J.; Payne, Vivienne H.; Moncet, Jean-Luc
  • Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 370, Issue 1968
  • https://doi.org/10.1098/rsta.2011.0295

Carbon monoxide, methane and carbon dioxide columns retrieved from SCIAMACHY by WFM-DOAS: year 2003 initial data set
journal, January 2005


Multispectrum analysis of the oxygen A-band
journal, January 2017


Bulk Scattering Properties for the Remote Sensing of Ice Clouds. Part II: Narrowband Models
journal, December 2005


Semi-autonomous sounding selection for OCO-2
journal, January 2013


An improved microcarb dispersive instrumental concept for the measurement of greenhouse gases concentration in the atmosphere
conference, November 2017

  • Pascal, V.; Buil, C.; Loesel, J.
  • International Conference on Space Optics 2014, International Conference on Space Optics — ICSO 2014
  • https://doi.org/10.1117/12.2304219

Validation of XCO 2 derived from SWIR spectra of GOSAT TANSO-FTS with aircraft measurement data
journal, January 2013


Preflight Spectral Calibration of the Orbiting Carbon Observatory 2
journal, May 2017


Comparisons of the Orbiting Carbon Observatory-2 (OCO-2) X CO 2 measurements with TCCON
journal, January 2017


Carbon source/sink information provided by column CO 2 measurements from the Orbiting Carbon Observatory
journal, January 2010


Quantifying the Impact of Atmospheric Transport Uncertainty on CO 2 Surface Flux Estimates
journal, April 2019


Orbiting Carbon Observatory: Inverse method and prospective error analysis: OCO INVERSE METHOD
journal, March 2008


Coupled surface-atmosphere reflectance (CSAR) model: 2. Semiempirical surface model usable with NOAA advanced very high resolution radiometer data
journal, January 1993


TCCON Philippines: First Measurement Results, Satellite Data and Model Comparisons in Southeast Asia
journal, November 2017


The Total Carbon Column Observing Network
journal, May 2011

  • Wunch, Debra; Toon, Geoffrey C.; Blavier, Jean-François L.
  • Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 369, Issue 1943
  • https://doi.org/10.1098/rsta.2010.0240

Direct space-based observations of anthropogenic CO 2 emission areas from OCO-2 : DIRECT OBSERVATIONS OF ANTHROPOGENIC CO
journal, November 2016


Reflectance quantities in optical remote sensing—definitions and case studies
journal, July 2006


TCCON data from Saga (JP), Release GGG2014.R0
dataset, September 2017


TCCON data from Réunion Island (RE), Release GGG2020.R0
dataset, January 2022


Estimating bias in the OCO-2 retrieval algorithm caused by 3-D radiation scattering from unresolved boundary layer clouds
journal, January 2015


TCCON data from Manaus (BR), Release GGG2014.R0
dataset, January 2014


Sources of variations in total column carbon dioxide
journal, January 2011


High accuracy absorption coefficients for the Orbiting Carbon Observatory-2 (OCO-2) mission: Validation of updated carbon dioxide cross-sections using atmospheric spectra
journal, December 2017


TCCON data from Lauder (NZ), 125HR, Release GGG2014.R0
dataset, September 2017


Using ocean-glint scattered sunlight as a diagnostic tool for satellite remote sensing of greenhouse gases
journal, January 2013


Contribution of the Orbiting Carbon Observatory to the estimation of CO 2 sources and sinks: Theoretical study in a variational data assimilation framework
journal, January 2007


TCCON data from Paris (FR), Release GGG2014.R0
dataset, January 2014


TCCON data from Réunion Island (RE), Release GGG2014.R0
dataset, September 2017


Consistent evaluation of ACOS-GOSAT, BESD-SCIAMACHY, CarbonTracker, and MACC through comparisons to TCCON
journal, January 2016


Influence of El Niño on atmospheric CO 2 over the tropical Pacific Ocean: Findings from NASA’s OCO-2 mission
journal, October 2017


Precision requirements for space-based data: REQUIREMENTS FOR SPACE-BASED
journal, May 2007


TCCON data from Lamont (US), Release GGG2014.R1
dataset, January 2016


Observational evidence of 3-D cloud effects in OCO-2 CO 2 retrievals: Evidence of 3-D Cloud Effects
journal, July 2017


A method for evaluating bias in global measurements of CO 2 total columns from space
journal, January 2011


Sensitivity of multiangle imaging to natural mixtures of aerosols over ocean
journal, August 2001


TCCON data from Park Falls (US), Release GGG2014.R0
dataset, January 2017


TCCON data from Darwin (AU), Release GGG2014.R0
dataset, September 2017


Spaceborne detection of localized carbon dioxide sources
journal, October 2017


Multispectrum Analysis of the Oxygen A-Band
conference, June 2016


TCCON data from Izana (ES), Release GGG2014.R0
dataset, September 2017


Online simulations of global aerosol distributions in the NASA GEOS-4 model and comparisons to satellite and ground-based aerosol optical depth
journal, January 2010


An atmospheric perspective on North American carbon dioxide exchange: CarbonTracker
journal, November 2007


TCCON data from Edwards (US), Release GGG2014.R1
dataset, January 2016


TCCON data from Tsukuba (JP), 125HR, Release GGG2014.R1
dataset, January 2016


Estimating surface CO 2 fluxes from space-borne CO 2 dry air mole fraction observations using an ensemble Kalman Filter
journal, January 2009


The Potential of the Geostationary Carbon Cycle Observatory (GeoCarb) to Provide Multi-scale Constraints on the Carbon Cycle in the Americas
journal, October 2018


TCCON data from Garmisch (DE), Release GGG2014.R0
dataset, September 2017


Long-range transport of stratospheric aerosols in the Southern Hemisphere following the 2015 Calbuco eruption
journal, January 2017


TCCON data from Bremen (DE), Release GGG2014.R0
dataset, September 2017


Calibration of the total carbon column observing network using aircraft profile data
journal, January 2010


TCCON data from Ascension Island (SH), Release GGG2014.R0
dataset, February 2017


Unified equations for the slope, intercept, and standard errors of the best straight line
journal, March 2004


The water vapour self-continuum by CRDS at room temperature in the 1.6µm transparency window
journal, November 2013


The utility of remotely sensed CO 2 concentration data in surface source inversions
journal, January 2001


On the Ability of Space-Based Passive and Active Remote Sensing Observations of CO 2 to Detect Flux Perturbations to the Carbon Cycle
journal, January 2018


The HITRAN2012 molecular spectroscopic database
journal, November 2013


The ACOS CO 2 retrieval algorithm – Part 1: Description and validation against synthetic observations
journal, January 2012


First Global Carbon Dioxide Maps Produced from TanSat Measurements
journal, April 2018


Evaluation and attribution of OCO-2 XCO 2 uncertainties
journal, January 2017


Measuring atmospheric carbon dioxide from space with the Orbiting Carbon Observatory-2 (OCO-2)
conference, September 2015


TCCON data from Ny Ålesund, Spitsbergen (NO), Release GGG2014.R0
dataset, October 2017


TCCON data from Réunion Island (RE), Release GGG2020.R0
dataset, January 2022


OCO-2 Level 2 bias-corrected XCO2 and other select fields from the full-physics retrieval aggregated as daily files, Retrospective processing V10r
dataset, January 2020


Probabilistic global maps of the CO 2 column at daily and monthly scales from sparse satellite measurements
journal, July 2017


Water vapor self-continuum absorption in near-infrared windows derived from laboratory measurements
journal, January 2011


Does GOSAT capture the true seasonal cycle of carbon dioxide?
journal, January 2015


Carbon dioxide retrieval from OCO-2 satellite observations using the RemoTeC algorithm and validation with TCCON measurements
journal, January 2018


Estimating bias in the OCO-2 retrieval algorithm caused by 3-D radiation scattering from unresolved boundary layer clouds
journal, January 2015


Consistent evaluation of ACOS-GOSAT, BESD-SCIAMACHY, CarbonTracker, and MACC through comparisons to TCCON
journal, January 2016


OCO-2 Level 2 bias-corrected XCO2 and other select fields from the full-physics retrieval aggregated as daily files, Retrospective processing V10r
dataset, January 2017


Works referencing / citing this record:

Accelerated MCMC for Satellite-Based Measurements of Atmospheric CO2
journal, September 2019


Towards monitoring localized CO 2 emissions from space: co-located regional CO 2 and NO 2 enhancements observed by the OCO-2 and S5P satellites
journal, January 2019


Evaluation of MOPITT Version 7 joint TIR-NIR XCO retrievals with TCCON
text, January 2019


A Geostatistical Framework for Quantifying the Imprint of Mesoscale Atmospheric Transport on Satellite Trace Gas Retrievals
journal, September 2019


Objective evaluation of surface- and satellite-driven carbon dioxide atmospheric inversions
journal, January 2019


Full-physics carbon dioxide retrievals from the Orbiting Carbon Observatory-2 (OCO-2) satellite by only using the 2.06 µm band
journal, January 2019


How bias correction goes wrong: measurement of X CO 2 affected by erroneous surface pressure estimates
journal, January 2019


Estimating power plant CO 2 emission using OCO-2 XCO 2 and high resolution WRF-Chem simulations
journal, July 2019


The 2015–2016 carbon cycle as seen from OCO-2 and the global in situ network
journal, January 2019


Net carbon emissions from African biosphere dominate pan-tropical atmospheric CO2 signal
journal, August 2019


Evaluation of MOPITT Version 7 joint TIR–NIR XCO retrievals with TCCON
journal, January 2019


The impact of improved aerosol priors on near-infrared measurements of carbon dioxide
journal, January 2019


Validation of OCO-2 error analysis using simulated retrievals
journal, January 2019


Classification of Anomalous Pixels in the Focal Plane Arrays of Orbiting Carbon Observatory-2 and -3 via Machine Learning
journal, December 2019


Southern California megacity CO 2 , CH 4 , and CO flux estimates using ground- and space-based remote sensing and a Lagrangian model
journal, January 2018


Analysis of Four Years of Global XCO2 Anomalies as Seen by Orbiting Carbon Observatory-2
journal, April 2019


Regional Impacts of COVID-19 on Carbon Dioxide Detected Worldwide from Space
preprint, January 2020


WOMBAT: A fully Bayesian global flux-inversion framework
preprint, January 2021


Objective evaluation of surface- and satellite-driven carbon dioxide atmospheric inversions
journal, January 2019


The 2015–2016 carbon cycle as seen from OCO-2 and the global in situ network
journal, January 2019


Methane retrieved from TROPOMI: improvement of the data product and validation of the first 2 years of measurements
journal, January 2021


Evaluation of MOPITT Version 7 joint TIR-NIR XCO retrievals with TCCON
text, January 2019


Overview: Estimating and reporting uncertainties in remotely sensed atmospheric composition and temperature
text, January 2020