References

ACP

Atmospheric Chemistry and Physics

ACP

1680-7324

Copernicus GmbH

Göttingen, Germany

10.5194/acp-10-5601-2010

Characterization of Tropospheric Emission Spectrometer (TES) CO2 for carbon cycle science

Kulawik

S. S.

¹ Jones

D. B. A.

² Nassar

² ³ Irion

F. W.

¹ Worden

J. R.

¹ Bowman

K. W.

¹ Machida

⁴ Matsueda

⁵ Sawa

⁴ Biraud

S. C.

⁶ Fischer

M. L.

⁷ Jacobson

A. R.

⁸

Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA, 91109, USA

University of Toronto, Department of Physics, Toronto, Ontario, Canada

University of Toronto, Department of Geography, Toronto, Ontario, Canada

National Institute for Environmental studies, 16-2 Onogawa, Tsukuba-City, Ibaraki, 305-8506, Japan

Meteorological Research Institute, 1-1 Nagamine, Tsukuba-City, Ibaraki, 305-0052, Japan

Lawrence Berkeley National Laboratory, Earth Sciences Division, Berkeley, CA, USA

E. O. Lawrence Berkeley National Laboratory, Environmental Energy Technologies Division, Berkeley, CA, USA

NOAA Earth System Research Lab, Global Monitoring Division, Boulder, Colorado, USA

25 06 2010

10 12 5601 5623

This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

This article is available from http://www.atmos-chem-phys.net/10/5601/2010/acp-10-5601-2010.html

The full text article is available as a PDF file from http://www.atmos-chem-phys.net/10/5601/2010/acp-10-5601-2010.pdf

We present carbon dioxide (CO2) estimates from the Tropospheric Emission Spectrometer (TES) on the EOS-Aura satellite launched in 2004. For observations between 40° S and 45° N, we find about 1 degree of freedom with peak sensitivity at 511 hPa. The estimated error is ~10 ppm for a single target and 1.3–2.3 ppm for monthly averages on spatial scales of 20°×30°. Monthly spatially-averaged TES data from 2005–2008 processed with a uniform initial guess and prior are compared to CONTRAIL aircraft data over the Pacific ocean, aircraft data at the Southern Great Plains (SGP) ARM site in the southern US, and the Mauna Loa and Samoa surface stations. Comparisons to Mauna Loa data show a correlation of 0.92, a standard deviation of 1.3 ppm, a predicted error of 1.2 ppm, and a ~2% low bias, which is subsequently corrected. Comparisons to SGP aircraft data over land show a correlation of 0.67 and a standard deviation of 2.3 ppm. TES data between 40° S and 45° N for 2006–2007 are compared to surface flask data, GLOBALVIEW, the Atmospheric Infrared Sounder (AIRS), and CarbonTracker. Comparison to GLOBALVIEW-CO2 ocean surface sites shows a correlation of 0.60 which drops when TES is offset in latitude, longitude, or time. At these same locations, TES shows a 0.62 and 0.67 correlation to CarbonTracker at the surface and 5 km, respectively. We also conducted an observing system simulation experiment to assess the potential utility of the TES data for inverse modeling of CO2 fluxes. We find that if biases in the data and model are well characterized, the averaged data have the potential to provide sufficient information to significantly reduce uncertainty on annual estimates of regional CO2 sources and sinks. Averaged pseudo-data at 10°×10° reduced uncertainty in flux estimates by as much as 70% for some tropical regions.

References 1

Baker, D. F., Law, R. M., Gurney, K. R., Rayner, P., Peylin, P., Denning, A. S., Bousquet, P., Bruhwiler, L., Chen, Y. H., Ciais, P., Fung, I. Y., Heimann, M., John, J., Maki, T., Maksyutov, S., Masarie, K., Prather, M., Pak, B., Taguchi, S., and Zhu, Z.: TransCom~3 inversion intercomparison: Impact of transport model errors on the interannual variability of regional CO2 fluxes, 1988–2003, Global Biogeochem. Cy., 20(1), GB1002, doi:10.1029/2004GB002439, 2006.

Barkley, M. P., Frieß, U., and Monks, P. S.: Measuring atmospheric CO2 from space using Full Spectral Initiation~(FSI) WFM-DOAS, Atmos. Chem. Phys., 6, 3517–3534, doi:10.5194/acp-6-3517-2006, 2006.

Beer, R. TES on the Aura mission: Scientific objectives, measurements, and analysis overview, IEEE T. Geosci. Remote, 44(5), 1102–1105, 2006.

Bey, I., Jacob, D. J., Yantosca, R. M., Logan, J. A., Field, B. D., Fiore, A. M., Li, Q. B., Liu, H. G. Y., Mickley, L. J., and Schultz, M. G.: Global modeling of tropospheric chemistry with assimilated meteorology: Model description and evaluation, J. Geophys. Res.-Atmos., 106(D19), 23073–23095, 2001.

Bösch, H., Toon, G. C., Sen, B., Washenfelder, R. A., Wennberg, P. O., Buchwitz, M., de Beek, R., Burrows, J. P., Crisp, D., Christi, M., Connor, B. J., Natraj, V., and Yung, Y. L.: Space-based near-infrared CO2 measurements: Testing the Orbiting Carbon Observatory retrieval algorithm and validation concept using SCIAMACHY observations over Park Falls, Wisconsin, J. Geophys. Res.-Atmos., 111(D23), doi:10.1029/2006JD007080, 2006.

Bowman, K. W., Rodgers, C. D., Kulawik, S. S., Worden, J., Sarkissian, E., Osterman, G., Steck, T., Lou, M., Eldering, A., Shephard, M., Worden, H., Lampel, M., Clough, S., Brown, P., Rinsland, C., Gunson, M., and Beer, R.: Tropospheric emission spectrometer: Retrieval method and error analysis, IEEE T. Geosci. Remote, 44(5), 1297–1307, 2006.

Buchwitz, M., de Beek, R., Burrows, J. P., Bovensmann, H., Warneke, T., Notholt, J., Meirink, J. F., Goede, A. P. H., Bergamaschi, P., Körner, S., Heimann, M., and Schulz, A.: Atmospheric methane and carbon dioxide from SCIAMACHY satellite data: initial comparison with chemistry and transport models, Atmos. Chem. Phys., 5, 941–962, doi:10.5194/acp-5-941-2005, 2005.

Buchwitz, M., Schneising, O., Burrows, J. P., Bovensmann, H., Reuter, M., and Notholt, J.: First direct observation of the atmospheric CO2 year-to-year increase from space, Atmos. Chem. Phys., 7, 4249–4256, doi:10.5194/acp-7-4249-2007, 2007.

Chahine, M., Barnet, C., Olsen, E. T., Chen, L., and Maddy, E.: On the determination of atmospheric minor gases by the method of vanishing partial derivatives with application to CO2, Geophys. Res. Lett., 32(22), doi:10.1029/2005GL024165, 2005.

Chahine, M. T., Chen, L., Dimotakis, P., Jiang, X., Li, Q. B., Olsen, E. T., Pagano, T., Randerson, J., and Yung, Y. L.: Satellite remote sounding of mid-tropospheric CO2, Geophys. Res. Lett., 35(17), doi:10.1029/2008GL035022, 2008.

Chevallier, F., Engelen, R. J., and Peylin, P.: The contribution of AIRS data to the estimation of CO2 sources and sinks, Geophys. Res. Lett., 32(23), L23801, doi:10.1029/2005GL024229, 2005.

Chevallier, F., Engelen, R. J., Carouge, C., Conway, T. J., Peylin, P., Pickett-Heaps, C., Ramonet, M., Rayner, P. J., and Xueref-Remy, I.: AIRS-based versus flask-based estimation of carbon surface fluxes, J. Geophys. Res.-Atmos., 114, D20303, doi:10.1029/2009JD012311, 2009.

Conway, T. J., Lang, P. M., and Masarie, K. A.: Atmospheric Carbon Dioxide Dry Air Mole Fractions from the NOAA~ESRL Carbon Cycle Cooperative Global Air Sampling Network, 1968–2007, Version: 2008-07-24, Path: ftp://ftp.cmdl.noaa.gov/ccg/co2/flask/event/, last access: August~2009, 2008.

Crevoisier, C., Chedin, A., and Scott, N. A.: AIRS channel selection for CO2 and other trace-gas retrievals, Q. J. Roy. Meteorol. Soc., 129(593), 2719–2740, 2003.

Crevoisier, C., Chédin, A., Matsueda, H., Machida, T., Armante, R., and Scott, N. A.: First year of upper tropospheric integrated content of CO2 from IASI hyperspectral infrared observations, Atmos. Chem. Phys., 9, 4797–4810, doi:10.5194/acp-9-4797-2009, 2009.

Crisp, D., Atlas, R. M., Breon, F.-M., Brown, L. R., Burrows, J. P., Ciais, P., Connor, B. J., Doney, S. C., Fung, I. Y., Jacob, D. J., Miller, C. E., O'Brien, D., Pawson, S., Randerson, J. T., Rayner, P., Salawitch, R. J., Sander, S. P., Sen, B., Stephens, G. L., Tans, P. P., Toon, G. C., Wennberg, P. O., Wofsy, S. C., Yung, Y. L., Kuang, Z., Chudasama, B., Sprague, G., Weiss, B., Pollock, R., Kenyon, D., and Schroll, S.: The Orbiting Carbon Observatory (OCO) mission, Adv. Space Res., 34(4), 700–709, 2004.

Dana, V., Mandin, J. Y., Guelachvili, G., Kou, Q., Morillonchapey, M., Wattson, R. B., and Rothman, L. S.: Intensities and Self-Broadening Coefficients of (CO2)-C-12-O-16 Lines in the Laser Band Region, J. Mol. Spectrosc., 152(1), 328–341, 1992.

Devi, V. M., Benner, D. C., Smith, M. A. H., Brown, L. R., and Dulick, M.: Multispectrum analysis of pressure broadening and pressure shift coefficients in the (CO2)-C-12-O-16 and (CO2)-C-13-O-16 laser bands, J. Quant. Spectrosc. Ra., 76(3–4), 411–434, 2003.

Eldering, A., Kulawik, S. S., Worden, J., Bowman, K., and Osterman, G.: Implementation of cloud retrievals for TES atmospheric retrievals: 2 Characterization of cloud top pressure and effective optical depth retrievals, J. Geophys. Res.-Atmos., 113(D16), D16S37, doi:10.1029/2007JD008858, 2008.

Engelen, R. J. and Stephens, G. L.: Information content of infrared satellite sounding measurements with respect to CO2, J. Appl. Meteorol., 43(1), 373–378, 2004.

Enting, I. G. and Mansbridge, J. V.: Latitudinal Distribution of Sources and Sinks of CO2 – Results of an Inversion Study, Tellus~B, 43(1), 156–170, 1991.

Feng, L., Palmer, P. I., Bösch, H., and Dance, S.: Estimating surface CO2 fluxes from space-borne CO2 dry air mole fraction observations using an ensemble Kalman Filter, Atmos. Chem. Phys., 9, 2619–2633, doi:10.5194/acp-9-2619-2009, 2009.

Fischer, M. L., Billesbach, D. P., Berry, J. A., Riley, W. J., and Torn, M. S.: Spatiotemporal variations in growing season exchanges of v, H2O, and sensible heat in agricultural fields of the Southern Great Plains, Earth Interact., 11(17), 1-21, 2007.

GLOBALVIEW-CO2: Cooperative Atmospheric Data Integration Project - Carbon Dioxide, CD-ROM, NOAA~ESRL, Boulder, Colorado, also available on Internet via anonymous FTP to ftp.cmdl.noaa.gov, last access: July~2009, Path: ccg/co2/GLOBALVIEW, 2008.

Gloor, M., Fan, S. M., Pacala, S., and Sarmiento, J.: Optimal sampling of the atmosphere for purpose of inverse modeling: A model study, Global Biogeochem. Cy., 14(1), 407–428, 2000.

Hamazaki, T., Kuze, A., and Kondo, K.: Sensor system for Greenhouse Gas Observing Satellite (GOSAT), Proceedings of SPIE-The International Society for Optical Engineering 2004, vol. 5543, edited by: Barnes, W. L., Infrared Spaceborne Remote Sensing~XII, Bellingham, WA, 275–282, 2004.

Hamazaki, T., Kuze, A., Team, G. P., and Agency, J. A. E.: CARBON DIOXIDE MONITORING FROM THE GOSAT SATELLITE, XXth~ISPRS Congress, Istanbul, Turkey, 2004.

Hansen, M. C., Defries, R. S., Townshend, J. R. G., and Sohlberg, R.: UMD Global Land Cover Classification, 1$\times$1 degree resolution, Department of Geography, University of Maryland, College Park, Maryland, 1981–1994, 1998.

Hansen, M. C., Defries, R. S., Townshend, J. R. G., and Sohlberg, R.: Global land cover classification at 1km spatial resolution using a classification tree approach, Int. J. Remote Sens., 21(6–7), 1331–1364, 2000.

Herman, R. L., Fisher, B. M., Shephard, M. W., Payne, V. H., Cady-Pereira, K. E., Kulawik, S. S., and Eldering, A.: Comparisons of Aura TES~V004 Temperature Retrievals With Sonde Measurements, Eos Trans. AGU, 89(53), Fall Meet. Suppl., Abstract A53A-0251, 2008.

Houweling, S., Breon, F.-M., Aben, I., Rödenbeck, C., Gloor, M., Heimann, M., and Ciais, P.: Inverse modeling of CO2 sources and sinks using satellite data: a synthetic inter-comparison of measurement techniques and their performance as a function of space and time, Atmos. Chem. Phys., 4, 523–538, doi:10.5194/acp-4-523-2004, 2004.

IPCC, 2007: Climate Change 2007: The Physical Science Basis, Contribution of Working Group~I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K. B., Tignor, M., and Miller, H. L., Cambridge University Press, Cambridge, UK and New York, NY, USA, 2007.

Johns, J. W. C. and Vanderauwera, J.: Absolute Intensities in CO2 – the V2~Fundamental near 15-Mu-M, J. Mol. Spectrosc., 140(1), 71–102, 1990.

Johns, J. W. C. and Noel, M.: Absolute Intensities in CO2 – the Laser Bands near 10-Mu-M, J. Mol. Spectrosc., 156(1), 403–414, 1992.

Jones, D. B. A., Bowman, K. W., Palmer, P. I., Worden, J. R., Jacob, D. J., Hoffman, R. N., Bey, I., and Yantosca, R. M.: Potential of observations from the Tropospheric Emission Spectrometer to constrain continental sources of carbon monoxide, J. Geophys. Res.-Atmos., 108(D24), 4789, doi:10.1029/2003JD003702, 2003.

Jones, D. B. A., Bowman, K. W., Logan, J. A., Heald, C. L., Liu, J., Luo, M., Worden, J., and Drummond, J.: The zonal structure of tropical O3 and CO as observed by the Tropospheric Emission Spectrometer in November~2004 - Part~1: Inverse modeling of CO emissions, Atmos. Chem. Phys., 9, 3547–3562, doi:10.5194/acp-9-3547-2009, 2009.

Kerola, D. X., Lampel, M. C., Shephard, M. W., Osterman, G. B., Herman, R. L., and Eldering, A.: Validation of Tropospheric Emission Spectrometer~(TES) Sea Surface Temperature~(SST) Retrievals, manuscript in preparation, 2010.

Kulawik, S. S., Osterman, G., Jones, D. B. A., and Bowman, K. W.: Calculation of altitude-dependent Tikhonov constraints for TES nadir retrievals, IEEE T. Geosci. Remote, 44(5), 1334–1342, 2006.

Kulawik, S. S., Bowman, K. W., Luo, M., Rodgers, C. D., and Jourdain, L.: Impact of nonlinearity on changing the a priori of trace gas profile estimates from the Tropospheric Emission Spectrometer~(TES), Atmos. Chem. Phys., 8, 3081–3092, doi:10.5194/acp-8-3081-2008, 2008.

Le Quere, C., Rodenbeck, C., Buitenhuis, E. T., Conway, T. J., Langenfelds, R., Gomez, A., Labuschagne, C., Ramonet, M., Nakazawa, T., Metzl, N., Gillett, N., and Heimann, M.: Saturation~5 of the Southern Ocean CO2 sink due to recent climate change, Science, 316, 1735-1738, 2007.

Luo, M., Rinsland, C., Fisher, B., Sachse, G., Diskin, G., Logan, J., Worden, H., Kulawik, S., Osterman, G., Eldering, A., Herman, R., and Shephard, M.: TES carbon monoxide validation with DACOM aircraft measurements during INTEX-B~2006, J. Geophys. Res.-Atmos., 112(D24), D24S48, doi:10.1029/2007JD008803, 2007.

Luo, M., Rinsland, C. P., Rodgers, C. D., Logan, J. A., Worden, H., Kulawik, S., Eldering, A., Goldman, A., Shephard, M. W., Gunson, M., and Lampel, M.: Comparison of carbon monoxide measurements by TES and MOPITT: Influence of a priori data and instrument characteristics on nadir atmospheric species retrievals, J. Geophys. Res.-Atmos., 112(D9), D09303, doi:10.1029/2006JD007663, 2007.

Machida, T., Matsueda, H., Sawa, Y., Nakagawa, Y., Hirotani, K., Kondo, N., Goto, K., Nakazawa, T., Ishikawa, K., and Ogawa, T.: Worldwide Measurements of Atmospheric CO2 and Other Trace Gas Species Using Commercial Airlines, J. Atmos. Ocean. Tech., 25(10), 1744–1754, 2008.

Maddy, E. S., Barnet, C. D., Goldberg, M., Sweeney, C., and Liu, X.: CO2 retrievals from the Atmospheric Infrared Sounder: Methodology and validation, J. Geophys. Res.-Atmos., 113(D11), D11301, doi:10.1029/2007JD009402, 2008.

Masarie, K. A. and Tans, P. P.: Extension and integration of atmospheric carbon dioxide data into a globally consistent measurement record, J. Geophys. Res.-Atmos, 100(D6), 11593–11610, 1995.

Matsueda, H., Inoue, H. Y., and Ishii, M.: Aircraft observation of carbon dioxide at 8–13 km altitude over the western Pacific from 1993 to 1999, Tellus~B, 54(1), 1–21, 2002.

Matsueda, H., Machida, T., Sawa, Y., Nakagawa, Y., Hirotani, K., Ikeda, H., Kondo, N., and Goto, K.: Evaluation of atmospheric CO2 measurements from new flask air sampling of JAL airliner observation, Pap. Meteorol. Geophys., 59, 1–17, 2008.

Nassar, R., Logan, J. A., Worden, H. M., Megretskaia, I. A., Bowman, K. W., Osterman, G. B., Thompson, A. M., Tarasick, D. W., Austin, S., Claude, H., Dubey, M. K., Hocking, W. K., Johnson, B. J., Joseph, E., Merrill, J., Morris, G. A., Newchurch, M., Oltmans, S. J., Posny, F., Schmidlin, F. J., Vomel, H., Whiteman, D. N., and Witte, J. C.: Validation of Tropospheric Emission Spectrometer~(TES) nadir ozone profiles using ozonesonde measurements, J. Geophys. Res.-Atmos., 113(D15), D15S17, doi:10.1029/2007JD008819, 2008.

Nassar, R., Jones, D. B. A., Suntharalingam, P., Chen, J. M., Andres, R. J., Wecht, K. J., Yantosca, R. M., Kulawik, S. S., Bowman, K. W., Worden, J. R., Machida, T., and Matsueda, H.: Modeling global atmospheric CO2 with improved emission inventories and CO2 production from the oxidation of other carbon species, Geosci. Model Develop. Discuss., submitted, GMD-2010-23, 2010.

Nassar, R., Jones, D. B. A., Kulawik, S. S., et al.: Quantifying CO2 sources and sinks with space-based CO2 observations, in preparation, 2010.

Olsen, E.: Validation of Six Years of Mid-Tropospheric CO2 Data from AIRS, NASA Sounder Science Team Meeting, Pasadena, CA, 4–7~May, 2009.

Osterman, G. B., Kulawik, S. S., Worden, H. M., Richards, N. A. D., Fisher, B. M., Eldering, A., Shephard, M. W., Froidevaux, L., Labow, G., Luo, M., Herman, R. L., Bowman, K. W., and Thompson, A. M.: Validation of Tropospheric Emission Spectrometer~(TES) measurements of the total, stratospheric, and tropospheric column abundance of ozone, J. Geophys. Res.-Atmos., 113(D15), D15S16, doi:10.1029/2007JD008801, 2008.

Osterman, G. B., Bowman, K., Eldering, A., Fisher, B., Herman, R., Jacob, D., Jourdain, L., Kulawik, S., Luo, M., Monarrez, R., Osterman, G., Paradise, S., Payne, V., Poosti, S., Richards, N., Rider, D., Shepard, D., Shephard, M., Vilnrotter, F., Worden, H., Worden, J., Yun, H., and Zhang, L.: Tropospheric Emission Spectrometer TES~L2 Data User's Guide, Version~4.0, Pasadena, Jet Propulsion Laboratory/California Institute of Technology, 2009.

Pak, B. C. and Prather, M. J.: CO2 source inversions using satellite observations of the upper troposphere, Geophys. Res. Lett., 28(24), 4571–4574, 2001.

Palmer, P. I., Jacob, D. J., Jones, D. B. A., Heald, C. L., Yantosca, R. M., Logan, J. A., Sachse, G. W., and Streets, D. G.: Inverting for emissions of carbon monoxide from Asia using aircraft observations over the western Pacific, J. Geophys. Res.-Atmos., 108(D21), 8828, doi:10.1029/2003JD003397, 2003.

Payne, V. H., Clough, S. A., Shephard, M. W., Nassar, R., and Logan, J. A.: Information-centered representation of retrievals with limited degrees of freedom for signal: Application to methane from the Tropospheric Emission Spectrometer, J. Geophys. Res.-Atmos., 114, D10307, doi:10.1029/2008JD010155, 2009.

Raupach, M.R., Marland, G., Ciais, P., Le Quere, C., Canadell, J. G., Klepper, G., and Field, C. B.: Global and regional drivers of accelerating CO2 emissions, P. Natl. Acad. Sci., 104(24), 10288–10293, doi:10.1073/pnas.0700609104, 2007.

Rayner, P. J., Enting, I. G., and Trudinger, C. M.: Optimizing the CO2 observing network for constraining sources and sinks, Tellus~B, 48(4), 433–444, 1996.

Rayner, P. J. and O'Brien, D. M.: The utility of remotely sensed CO2 concentration data in surface source inversions, Geophys. Res. Lett., 28(1), 175–178, 2001.

Richards, N. A. D., Osterman, G. B., Browell, E. V., Hair, J. W., Avery, M., and Li, Q. B.: Validation of Tropospheric Emission Spectrometer ozone profiles with aircraft observations during the intercontinental chemical transport experiment-B, J. Geophys. Res.-Atmos., 113(D16), D16S29, doi:10.1029/2007JD008815, 2008.

Riley, W. J., Biraud, S. C., Torn, M. S., Fischer, M. L., Billesbach, D. P., and Berry, J. A.: Regional CO2 and latent heat surface fluxes in the Southern Great Plains: Measurements, modeling, and scaling, J. Geophys. Res., in press, 2009.

Rinsland, C. P., Luo, M., Logan, J. A., Beer, R., Worden, H., Kulawik, S. S., Rider, D., Osterman, G., Gunson, M., Eldering, A., Goldman, A., Shephard, M., Clough, S. A., Rodgers, C., Lampel, M., and Chiou, L.: Nadir measurements of carbon monoxide distributions by the Tropospheric Emission Spectrometer instrument onboard the Aura Spacecraft: Overview of analysis approach and examples of initial results, Geophys. Res. Lett., 33(22), L22806, doi:10.1029/2006GL027000, 2006.

Shephard, M. W., Worden, H. M., Cady-Pereira, K. E., Lampel, M., Luo, M., Bowman, K. W., Sarkissian, E., Beer, R., Rider, D. M., Tobin, D. C., Revercomb, H. E., Fisher, B. M., Tremblay, D., Clough, S. A., Osterman, G. B., and Gunson, M.: Tropospheric Emission Spectrometer nadir spectral radiance comparisons, J. Geophys. Res., 113, D15S05, doi:10.1029/2007JD008856, 2008.

Stephens, B. B., Gurney, K. R., Tans, P. P., Sweeney, C., Peters, W., Bruhwiler, L., Ciais, P., Ramonet, M., Bousquet, P., Nakazawa, T., Aoki, S., Machida, T., Inoue, G., Vinnichenko, N., Lloyd, J., Jordan, A., Heimann, M., Shibistova, O., Langenfelds, R. L., Steele, L. P., Francey, R. J., and Denning, A. S.: Weak northern and strong tropical land carbon uptake from vertical profiles of atmospheric CO2, Science, 316(5832), 1732–1735, 2007.

Strow, L. L. and Hannon, S. E.: A 4-year zonal climatology of lower tropospheric CO2 derived from ocean-only Atmospheric Infrared Sounder observations, J. Geophys. Res.-Atmos., 113(D18), D18302, doi:10.1029/2007JD009713, 2008.

Suntharalingam, P., Spivakovsky, C. M., Logan, J. A., and McElroy, M. B.: Estimating the distribution of terrestrial CO2 sources and sinks from atmospheric measurements: Sensitivity to configuration of the observation network, J. Geophys. Res.-Atmos., 108(D15), 4452, doi:10.1029/2002JD002207, 2003.

Suntharalingam, P., Jacob, D. J., Palmer, P. I., Logan, J. A., Yantosca, R. M., Xiao, Y. P., Evans, M. J., Streets, D. G., Vay, S. L., and Sachse, G. W.: Improved quantification of Chinese carbon fluxes using CO2/CO correlations in Asian outflow, J. Geophys. Res.-Atmos., 109(D18), D18S18, doi:10.1029/2003JD004362, 2004.

Tans, P. P., Fung, I. Y., and Takahashi, T.: Observational Constraints on the Global Atmospheric CO2 Budget, Science, 247(4949), 1431–1438, 1990.

Tans, P. P. and Conway, T. J.: Monthly atmospheric CO2 mixing ratios from the NOAA~CMDL carbon cycle cooperative global air sampling network, 1968–2002, a Compendium of Data on Global Change, Carbon Dioxide Inf. Anal. Center, Oak Ridge, Tenn., Oak Ridge Natl. Lab., US Dep. of Energy., 2005.

Wang, H., Jacob, D. J., Kopacz, M., Jones, D. B. A., Suntharalingam, P., Fisher, J. A., Nassar, R., Pawson, S., and Nielsen, J. E.: Error correlation between CO2 and CO as constraint for CO2 flux inversions using satellite data, Atmos. Chem. Phys., 9, 7313–7323, doi:10.5194/acp-9-7313-2009, 2009.

Worden, J., Kulawik, S. S., Shephard, M. W., Clough, S. A., Worden, H., Bowman, K., and Goldman, A.: Predicted errors of tropospheric emission spectrometer nadir retrievals from spectral window selection, J. Geophys. Res.-Atmos., 109(D9), D09308, doi:10.1029/2004JD004522, 2004.

Worden, H. M., Logan, J. A., Worden, J. R., Beer, R., Bowman, K., Clough, S. A., Eldering, A., Fisher, B. M., Gunson, M. R., Herman, R. L., Kulawik, S. S., Lampel, M. C., Luo, M., Megretskaia, I. A., Osterman, G. B., and Shephard, M. W.: Comparisons of Tropospheric Emission Spectrometer~(TES) ozone profiles to ozonesondes: Methods and initial results, J. Geophys. Res.-Atmos., 112(D3), D03309, doi:10.1029/2006JD007258, 2007.

Yokota, T., Yoshida, Y., Eguchi, N., Ota, Y., Tanaka, T., Watanabe, H., and Maksyutov, S.: Global Concentrations of CO2 and CH4 Retreived from GOSAT: first Preliminary Results, Sci. Online Lett. Atmos., 5, 160–163, doi:10.2151/sola.2009-041, 2009.