References

ACP

Atmospheric Chemistry and Physics

ACP

1680-7324

Copernicus GmbH

Göttingen, Germany

10.5194/acp-11-2863-2011

Long-term analysis of carbon dioxide and methane column-averaged mole fractions retrieved from SCIAMACHY

Schneising

¹ Buchwitz

¹ Reuter

¹ Heymann

¹ Bovensmann

¹ Burrows

J. P.

Institute of Environmental Physics (IUP), University of Bremen FB1, Bremen, Germany

28 03 2011

11 6 2863 2880

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.

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The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/2863/2011/acp-11-2863-2011.pdf

Carbon dioxide (CO2) and methane (CH4) are the two most important anthropogenic greenhouse gases contributing to global climate change. SCIAMACHY onboard ENVISAT (launch 2002) was the first and is now with TANSO onboard GOSAT (launch 2009) one of only two satellite instruments currently in space whose measurements are sensitive to CO2 and CH4 concentration changes in the lowest atmospheric layers where the variability due to sources and sinks is largest. We present long-term SCIAMACHY retrievals (2003–2009) of column-averaged dry air mole fractions of both gases (denoted XCO2 and XCH4) derived from absorption bands in the near-infrared/shortwave-infrared (NIR/SWIR) spectral region focusing on large-scale features. The results are obtained using an upgraded version (v2) of the retrieval algorithm WFM-DOAS including several improvements, while simultaneously maintaining its high processing speed. The retrieved mole fractions are compared to global model simulations (CarbonTracker XCO2 and TM5 XCH4) being optimised by assimilating highly accurate surface measurements from the NOAA/ESRL network and taking the SCIAMACHY averaging kernels into account. The comparisons address seasonal variations and long-term characteristics. The steady increase of atmospheric carbon dioxide primarily caused by the burning of fossil fuels can be clearly observed with SCIAMACHY globally. The retrieved global annual mean XCO2 increase agrees with CarbonTracker within the error bars (1.80±0.13 ppm yr−1 compared to 1.81±0.09 ppm yr−1). The amplitude of the XCO2 seasonal cycle as retrieved by SCIAMACHY, which is 4.3±0.2 ppm for the Northern Hemisphere and 1.4±0.2 ppm for the Southern Hemisphere, is on average about 1 ppm larger than for CarbonTracker. An investigation of the boreal forest carbon uptake during the growing season via the analysis of longitudinal gradients shows good agreement between SCIAMACHY and CarbonTracker concerning the overall magnitude of the gradients and their annual variations. The analysis includes a discussion of the relative uptake strengths of the Russian and North American boreal forest regions. The retrieved XCH4 results show that after years of stability, atmospheric methane has started to rise again in recent years which is consistent with surface measurements. The largest increase is observed for the tropics and northern mid- and high-latitudes amounting to about 7.5±1.5 ppb yr−1 since 2007. Due care has been exercised to minimise the influence of detector degradation on the quantitative estimate of this anomaly.

References 1

Aumann,~H H., Gregorich,~D., and Gaiser,~S.: AIRS hyper-spectral measurements for climate research: carbon dioxide and nitrous oxide effects, Geophys. Res. Lett., 32, L05806, http://dx.doi.org/10.1029/2004GL021784doi:10.1029/2004GL021784, 2005.

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, http://dx.doi.org/10.5194/acp-6-3517-2006doi:10.5194/acp-6-3517-2006, 2006a.

Barkley,~M P., Monks,~P S., and Engelen,~R J.: Comparison of SCIAMACHY and AIRS CO2 measurements over North America during the summer and autumn of 2003, Geophys. Res. Lett., 33, L20805, http://dx.doi.org/10.1029/2006GL026807doi:10.1029/2006GL026807, 2006b.

Barkley,~M P., Monks,~P S., Frieß,~U., Mittermeier,~R L., Fast,~H., Körner,~S., and Heimann,~M.: Comparisons between SCIAMACHY atmospheric CO2 retrieved using (FSI) WFM-DOAS to ground based FTIR data and the TM3 chemistry transport model, Atmos. Chem. Phys., 6, 4483–4498, http://dx.doi.org/10.5194/acp-6-4483-2006doi:10.5194/acp-6-4483-2006, 2006c.

Barkley,~M P., Monks,~P S., Hewitt,~A J., Machida,~T., Desai,~A., Vinnichenko,~N., Nakazawa,~T., Yu Arshinov,~M., Fedoseev,~N., and Watai,~T.: Assessing the near surface sensitivity of SCIAMACHY atmospheric CO2 retrieved using (FSI) WFM-DOAS, Atmos. Chem. Phys., 7, 3597–3619, http://dx.doi.org/10.5194/acp-7-3597-2007doi:10.5194/acp-7-3597-2007, 2007.

Bergamaschi,~P., Frankenberg,~C., Meirink,~J F., Krol,~M., Dentener,~F., Wagner,~T., Platt,~U., Kaplan,~J O., Körner,~S., Heimann,~M., Dlugokencky,~E J., and Goede,~A.: Satellite chartography of atmospheric methane from SCIAMACHY onboard ENVISAT: 2 Evaluation based on inverse model simulations, J Geophys. Res., 112, D02304, http://dx.doi.org/10.1029/2006JD007268doi:10.1029/2006JD007268, 2007.

Bergamaschi,~P., Frankenberg,~C., Meirink,~J F., Krol,~M., Villani,~M G., Houweling,~S., Dentener,~F., Dlugokencky,~E J., Miller,~J B., Gatti,~L V., Engel,~A., and Levin,~I.: Inverse modeling of global and regional CH4 emissions using SCIAMACHY satellite retrievals, J Geophys. Res., 114, D22301, http://dx.doi.org/10.1029/2009JD012287doi:10.1029/2009JD012287, 2009.

Bloom,~A A., Palmer,~P I., Fraser,~A., Reay,~D S., and Frankenberg,~C.: Large-scale controls of methanogenesis inferred from methane and gravity spaceborne data, Science, 327, 322–325, http://dx.doi.org/10.1126/science.1175176doi:10.1126/science.1175176, 2010.

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., 111, D23302, http://dx.doi.org/10.1029/2006JD007080doi:10.1029/2006JD007080, 2006.

Bousquet,~P., Ciais,~P., Miller,~J B., Dlugokencky,~E J., Hauglustaine,~D A., Prigent,~C., Van~der Werf,~G R., Peylin,~P., Brunke,~E.-G., Carouge,~C., Langenfelds,~R L., Lathiere,~J., Papa,~F., Ramonet,~M., Schmidt,~M., Steele,~L P., Tyler,~S C., and White,~J.: Contribution of anthropogenic and natural sources to atmospheric methane variability, Nature, 443, 439–443, http://dx.doi.org/10.1038/nature05132doi:10.1038/nature05132, 2006.

Bovensmann,~H., Burrows,~J P., Buchwitz,~M., Frerick,~J., Noël,~S., Rozanov,~V V., Chance,~K V., and Goede,~A.: SCIAMACHY – mission objectives and measurement modes, J Atmos. Sci., 56, 127–150, 1999.

Bramstedt,~K.: Calculation of SCIAMACHY M-Factors, Technical Note, IFE-SCIA-TN-2007-01-CalcMFactor, Issue:~1, available online at: http://www.iup.uni-bremen.de/sciamachy/mfactors/mfactor-TN-1-0.pdf, 2008.

Buchwitz,~M. and Burrows,~J P.: Retrieval of CH4, CO, and CO2 total column amounts from SCIAMACHY near-infrared nadir spectra: retrieval algorithm and first results, in: Remote Sensing of Clouds and the Atmosphere VIII, edited by: Schäfer,~K P., Comèron,~A., Carleer,~M R., and Picard,~R H., P SPIE, 5235, 375–388, 2004.

Buchwitz,~M., Rozanov,~V V., and Burrows,~J P.: A~correlated-k distribution scheme for overlapping gases suitable for retrieval of atmospheric constituents from moderate resolution radiance measurements in the visible/near-infrared spectral region, J Geophys. Res., 105, 15247–15261, 2000.

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, http://dx.doi.org/10.5194/acp-5-941-2005doi:10.5194/acp-5-941-2005, 2005a.

Buchwitz,~M., de Beek,~R., No\"el,~S., Burrows,~J P., Bovensmann,~H., Bremer,~H., Bergamaschi,~P., Körner,~S., and Heimann,~M.: Carbon monoxide, methane and carbon dioxide columns retrieved from SCIAMACHY by WFM-DOAS: year 2003 initial data set, Atmos. Chem. Phys., 5, 3313–3329, http://dx.doi.org/10.5194/acp-5-3313-2005doi:10.5194/acp-5-3313-2005, 2005b.

Buchwitz,~M., de Beek,~R., No\"el,~S., Burrows,~J P., Bovensmann,~H., Schneising,~O., Khlystova,~I., Bruns,~M., Bremer,~H., Bergamaschi,~P., Körner,~S., and Heimann,~M.: Atmospheric carbon gases retrieved from SCIAMACHY by WFM-DOAS: version 0.5 CO and CH4 and impact of calibration improvements on CO2 retrieval, Atmos. Chem. Phys., 6, 2727–2751, http://dx.doi.org/10.5194/acp-6-2727-2006doi:10.5194/acp-6-2727-2006, 2006.

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, http://dx.doi.org/10.5194/acp-7-4249-2007doi:10.5194/acp-7-4249-2007, 2007.

Burrows,~J P. and Chance,~K V.: Scanning imaging absorption spectrometer for atmospheric chartography, in: Future European and Japanese Remote Sensing Sensors and Programs, edited by: Slater,~P N., P SPIE, 1490, 146–155, 1991.

Burrows,~J P., Schneider,~W., Geary,~J C., Chance,~K V., Goede,~A P H., Aarts,~H J M., de~Vries,~J., Smorenburg,~C., and Visser,~H.: Atmospheric remote sensing with SCIAMACHY, Digest of Topical Meeting on Optical Remote Sensing of the Atmosphere, Optical Society of America, Washington DC, USA, 4, 71–74, 1990.

Burrows,~J P., Hölzle,~E., Goede,~A P H., Visser,~H., and Fricke,~W.: SCIAMACHY – scanning imaging absorption spectrometer for atmospheric chartography, Acta Astronaut., 35, 445–451, 1995.

Chédin,~A., Hollingsworth,~A., Scott,~N A., Serrar,~S., Crevoisier,~C., and Armante,~R.: Annual and seasonal variations of atmospheric CO2, \chemN_2O and CO concentrations retrieved from NOAA/TOVS satellite observations, Geophys. Res. Lett., 29, 1269, http://dx.doi.org/10.1029/2001GL014082doi:10.1029/2001GL014082, 2002.

Chédin,~A., Serrar,~S., Scott,~N A., Crevoisier,~C., and Armante,~R.: First global measurement of midtropospheric CO2 from NOAA polar satellites: tropical zone, J Geophys. Res., 108, 4581, http://dx.doi.org/10.1029/2003JD003439doi:10.1029/2003JD003439, 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, http://dx.doi.org/10.5194/acp-9-4797-2009doi:10.5194/acp-9-4797-2009, 2009a.

Crevoisier,~C., Nobileau,~D., Fiore,~A M., Armante,~R., Chédin,~A., and Scott,~N A.: Tropospheric methane in the tropics – first year from IASI hyperspectral infrared observations, Atmos. Chem. Phys., 9, 6337–6350, http://dx.doi.org/10.5194/acp-9-6337-2009doi:10.5194/acp-9-6337-2009, 2009b.

Dlugokencky,~E J., Bruhwiler,~L., White,~J W C., Emmons,~L K., Novelli,~P C., Montzka,~S A., Masarie,~K A., Lang,~P M., Crotwell,~A M., Miller,~J B., and Gatti,~L V.: Observational constraints on recent increases in the atmospheric CH4 burden, Geophys. Res. Lett., 36, L18803, http://dx.doi.org/10.1029/2009GL039780doi:10.1029/2009GL039780, 2009.

Dlugokencky,~E J., Lang,~P M., and Masarie,~K A.: Atmospheric methane dry air mole fractions from the NOAA ESRL carbon cycle cooperative global air sampling network, 1983–2009, version: 2010-08-12, available online at: ftp://ftp.cmdl.noaa.gov/ccg/ch4/flask/event/, last access: 8 September 2010, 2010.

Engelen,~R J. and McNally,~A P.: Estimating atmospheric CO2 from advanced infrared satellite radiances within an operational 4D-Var data assimilation system: results and validation, J Geophys. Res., 109, D18305, http://dx.doi.org/10.1029/2005JD005982doi:10.1029/2005JD005982, 2005.

Engelen,~R J., Andersson,~E., Chevallier,~F., Hollingsworth,~A., Matricardi,~M., McNally,~A P., Thépaut,~J.-N., and Watts,~P D.: Estimating atmospheric CO2 from advanced infrared satellite radiances within an operational 4D-Var data assimilation system: methodology and first results, J Geophys. Res., 109, D19309, http://dx.doi.org/10.1029/2004JD004777doi:10.1029/2004JD004777, 2004.

Frankenberg,~C., Meirink,~J F., van Weele,~M., Platt,~U., and Wagner,~T.: Assessing methane emissions from global spaceborne observations, Science, 308, 1010–1014, http://dx.doi.org/10.1126/doi:10.1126/science.1106644, 2005.

Frankenberg,~C., Meirink,~J F., Bergamaschi,~P., Goede,~A P H., Heimann,~M., Körner,~S., Platt,~U., van Weele,~M., and Wagner,~T.: Satellite chartography of atmospheric methane from SCIAMACHY onboard ENVISAT: analysis of the years 2003 and 2004, J Geophys. Res., 111, D07303, http://dx.doi.org/10.1029/2005JD006235doi:10.1029/2005JD006235, 2006.

Frankenberg,~C., Warneke,~T., Butz,~A., Aben,~I., Hase,~F., Spietz,~P., and Brown,~L R.: Pressure broadening in the 2$\nu_3$ band of methane and its implication on atmospheric retrievals, Atmos. Chem. Phys., 8, 5061–5075, http://dx.doi.org/10.5194/acp-8-5061-2008doi:10.5194/acp-8-5061-2008, 2008a.

Frankenberg,~C., Bergamaschi,~P., Butz,~A., Houweling,~S., Meirink,~J F., Notholt,~J., Petersen,~A K., Schrijver,~H., Warneke,~T., and Aben,~I.: Tropical methane emissions: a revised view from SCIAMACHY onboard ENVISAT, Geophys. Res. Lett., 35, L15811, http://dx.doi.org/10.1029/doi:10.1029/2008GL034300, 2008b.

Frankenberg,~C., Aben,~I., Bergamaschi,~P., Dlugokencky,~E J., van Hees,~R., Houweling,~S., van der Meer,~P., Snel,~R., and Tol,~P.: Global column-averaged methane mixing ratios from 2003 to 2009 as derived from SCIAMACHY: Trends and variability, J Geophys. Res., 116, D04302, http://dx.doi.org/10.1029/doi:10.1029/2010JD014849, 2011.

Gloudemans,~A M S., Schrijver,~H., Kleipool,~Q., van den Broek,~M M P., Straume,~A G., Lichtenberg,~G., van Hees,~R M., Aben,~I., and Meirink,~J F.: The impact of SCIAMACHY near-infrared instrument calibration on CH4 and CO total columns, Atmos. Chem. Phys., 5, 2369–2383, http://dx.doi.org/10.5194/acp-5-2369-2005doi:10.5194/acp-5-2369-2005, 2005.

Herman,~J R., Bhartia,~P K., Torres,~O., Hsu,~C., Seftor,~C., and Celarier,~E.: Global distribution of UV absorbing aerosols from Nimbus7/TOMS data, J Geophys. Res., 102, 16911–16922, 1997.

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, http://dx.doi.org/10.5194/acp-4-523-2004doi:10.5194/acp-4-523-2004, 2004.

Houweling,~S., Hartmann,~W., Aben,~I., Schrijver,~H., Skidmore,~J., Roelofs,~G.-J., and Breon,~F.-M.: Evidence of systematic errors in SCIAMACHY-observed CO2 due to aerosols, Atmos. Chem. Phys., 5, 3003–3013, http://dx.doi.org/10.5194/acp-5-3003-2005doi:10.5194/acp-5-3003-2005, 2005.

Jenouvrier,~A., Daumont,~L., Régalia-Jarlot,~L., Tyuterev,~V G., Carleer,~M., Vandaele,~A C., Mikhailenko,~S., and Fally,~S.: Fourier transform measurements of water vapor line parameters in the 4200–6600 cm−1 region, J Quant. Spectrosc. Ra., 105, 326–355, http://dx.doi.org/10.1016/j.jqsrt.2006.11.007doi:10.1016/j.jqsrt.2006.11.007, 2007.

Keppel-Aleks,~G., Wennberg,~P O., and Schneider,~T.: Sources of variations in total column carbon dioxide, Atmos. Chem. Phys. Discuss., 10, 30569–30611, http://dx.doi.org/10.5194/acpd-10-30569-2010doi:10.5194/acpd-10-30569-2010, 2010.

Krol,~M., Houweling,~S., Bregman,~B., van den Broek,~M., Segers,~A., van Velthoven,~P., Peters,~W., Dentener,~F., and Bergamaschi,~P.: The two-way nested global chemistry-transport zoom model TM5: algorithm and applications, Atmos. Chem. Phys., 5, 417–432, http://dx.doi.org/10.5194/acp-5-417-2005doi:10.5194/acp-5-417-2005, 2005.

Kulawik,~S S., Jones,~D B A., Nassar,~R., Irion,~F W., Worden,~J R., Bowman,~K W., Machida,~T., Matsueda,~H., Sawa,~Y., Biraud,~S C., Fischer,~M L., and Jacobson,~A R.: Characterization of Tropospheric Emission Spectrometer (TES) CO2 for carbon cycle science, Atmos. Chem. Phys., 10, 5601–5623, http://dx.doi.org/10.5194/acp-10-5601-2010doi:10.5194/acp-10-5601-2010, 2010.

Lichtenberg,~G., Kleipool,~Q., Krijger,~J M., van Soest,~G., van Hees,~R., Tilstra,~L G., Acarreta,~J R., Aben,~I., Ahlers,~B., Bovensmann,~H., Chance,~K., Gloudemans,~A M S., Hoogeveen,~R W M., Jongma,~R T N., Noël,~S., Piters,~A., Schrijver,~H., Schrijvers,~C., Sioris,~C E., Skupin,~J., Slijkhuis,~S., Stammes,~P. and Wuttke,~M.: SCIAMACHY Level 1 data: calibration concept and in-flight calibration, Atmos. Chem. Phys., 6, 5347–5367, http://dx.doi.org/10.5194/acp-6-5347-2006doi:10.5194/acp-6-5347-2006, 2006.

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., 113, D11301, http://dx.doi.org/10.1029/2007JD009402doi: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., 100, D6, 11593–11610, http://dx.doi.org/10.1029/95JD00859doi:10.1029/95JD00859, 1995.

Peters,~W., Jacobson,~A R., Sweeney,~C., Andrews,~A E., Conway,~T J., Masarie,~K., Miller,~J B., Bruhwiler,~L M P., Pétron,~G., Hirsch,~A I., Worthy,~D E J., van~der Werf,~G R., Randerson,~J T., Wennberg,~P O., Krol,~M C., and Tans,~P P.: An atmospheric perspective on North American carbon dioxide exchange: CarbonTracker, P. Natl. Acad. Sci. USA, 104, 18925–18930, 2007.

Peters,~W., Krol,~M C., van~der Werf,~G R., Houweling,~S., Jones,~C D., Hughes,~J., Schaefer,~K., Masarie,~K A., Jacobson,~A R., Miller,~J B., Cho,~C H., Ramonet,~M., Schmidt,~M., Ciattaglia,~L., Apadula,~F., Heltai,~D., Meinhardt,~F., di~Sarra,~A G., Piacentino,~S., Sferlazzo,~D., Aalto,~T., Hatakka,~J., Ström,~J., Haszpra,~L., Meijer,~H A J., van~der Laan,~S., Neubert,~R E M., Jordan,~A., Rodó,~X., Morgu\'i,~J.-A., Vermeulen,~A T., Popa,~E., Rozanski,~K., Zimnoch,~M., Manning,~A C., Leuenberger,~M., Uglietti,~C., Dolman,~A J., Ciais,~P., Heimann,~M., and Tans,~P P.: Seven years of recent European net terrestrial carbon dioxide exchange constrained by atmospheric observations, Glob. Change Biol., 16, 1317–1337, http://dx.doi.org/10.1111/j.1365-2486.2009.02078.xdoi:10.1111/j.1365-2486.2009.02078.x, 2010.

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

Reuter,~M., Buchwitz,~M., Schneising,~O., Heymann,~J., Bovensmann,~H., and Burrows,~J P.: A~method for improved SCIAMACHY CO2 retrieval in the presence of optically thin clouds, Atmos. Meas. Tech., 3, 209–232, http://dx.doi.org/10.5194/amt-3-209-2010doi:10.5194/amt-3-209-2010, 2010.

Rigby,~M., Prinn,~R G., Fraser,~P J., Simmonds,~P G., Langenfelds,~R L., Huang,~J., Cunnold,~D M., Steele,~L P., Krummel,~P B., Weiss,~R F., O'Doherty,~S., Salameh,~P K., Wang,~H J., Harth,~C M., Mühle,~J., and Porter,~L W.: Renewed growth of atmospheric methane, Geophys. Res. Lett., 35, L22805, http://dx.doi.org/10.1029/2008GL036037doi:10.1029/2008GL036037, 2008.

Rothman,~L S., Jaquemart,~D., Barbe,~A., Benner,~D C., Birk,~M., Brown,~L R., Carleer,~M R., Chackerian,~C., Chance,~K., Coudert,~L H., Dana,~V., Devi,~V M., Flaud,~J.-M., Gamache,~R R., Goldman,~A., Hartmann,~J.-M., Jucks,~K W., Maki,~A G., Mandin,~J.-Y., Massie,~S T., Orphal,~J., Perrin,~A., Rinsland,~C P., Smith,~M A H., Tennyson,~J., Tolchenov,~R N., Toth,~R A., Vander~Auwera,~J., Varanasi,~P., and Wagner,~G.: The HITRAN 2004 molecular spectroscopic database, J Quant. Spectrosc. Ra., 96, 139–204, http://dx.doi.org/10.1016/j.jqsrt.2004.10.008doi:10.1016/j.jqsrt.2004.10.008, 2005.

Rothman,~L S., Gordon,~I E., Barbe,~A., Benner,~D C., Bernath,~P F., Birk,~M., Boudon,~V., Brown,~L R., Campargue,~A., Champion,~J.-P., Chance,~K., Coudert,~L H., Dana,~V., Devi,~V M., Fally,~S., Flaud,~J.-M., Gamache,~R R., Goldman,~A., Jaquemart,~D., Kleiner,~I., Lacome,~N., Lafferty,~W J., Mandin,~J.-Y., Massie,~S T., Mikhailenko,~S N., Miller,~C E., Moazzen-Ahmadi,~N., Naumenko,~O V., Nikitin,~A V., Orphal,~J., Perevalov,~V I., Perrin,~A., Predoi-Cross,~A., Rinsland,~C P., Rotger,~M., Simeckova,~M., Smith,~M A H., Sung,~K., Tashkun,~S A., Tennyson,~J., Toth,~R A., Vandaele,~A C., and Auwera,~J V.: The HITRAN 2008 molecular spectroscopic database, J Quant. Spectrosc. Ra., 110, 533–572, http://dx.doi.org/10.1016/j.jqsrt.2009.02.013doi:10.1016/j.jqsrt.2009.02.013, 2009.

Schneising,~O., Buchwitz,~M., Burrows,~J P., Bovensmann,~H., Reuter,~M., Notholt,~J., Macatangay,~R., and Warneke,~T.: Three years of greenhouse gas column-averaged dry air mole fractions retrieved from satellite – Part~1: Carbon dioxide, Atmos. Chem. Phys., 8, 3827–3853, http://dx.doi.org/10.5194/acp-8-3827-2008doi:10.5194/acp-8-3827-2008, 2008.

Schneising,~O., Buchwitz,~M., Burrows,~J P., Bovensmann,~H., Bergamaschi,~P., and Peters,~W.: Three years of greenhouse gas column-averaged dry air mole fractions retrieved from satellite – Part~2: Methane, Atmos. Chem. Phys., 9, 443–465, http://dx.doi.org/10.5194/acp-9-443-2009doi:10.5194/acp-9-443-2009, 2009.

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

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, 1732–1735, 2007.

Strow,~L L., Hannon,~S E., De-Souza Machado,~S., Motteler,~H E., and Tobin,~D C.: Validation of the Atmospheric Infrared Sounder radiative transfer algorithm, J Geophys. Res., 111, D09S06, http://dx.doi.org/10.1029/2005JD006146doi:10.1029/2005JD006146, 2006.

Tilstra,~L G., de~Graaf,~M., Aben,~I., and Stammes,~P.: Analysis of 5 years of SCIAMACHY absorbing aerosol index data, Proceedings ENVISAT Symposium, Montreux, Switzerland, 23–27~April 2007, ESA Special Publication SP-636, 2007.

Yang,~Z., Washenfelder,~R A., Keppel-Aleks,~G., Krakauer,~N Y., Randerson,~J T., Tans,~P P., Sweeney,~C., and Wennberg,~P O.: New constraints on Northern Hemisphere growing season net flux, Geophys. Res. Lett., 34, L12807, http://dx.doi.org/10.1029/2007GL029742doi:10.1029/2007GL029742, 2007.

Yokota,~T., Yoshida,~Y., Eguchi,~N., Ota,~Y., Tanaka,~T., Watanabe,~H., and Maksyutov,~S.: Global concentrations of CO2 and CH4 retrieved from GOSAT: first preliminary results, SOLA, 5, 160–163, http://dx.doi.org/10.2151/sola.2009-041doi:10.2151/sola.2009-041, 2009.