Comparisons between SCIAMACHY and ground-based FTIR data for total columns of CO, CH4, CO2 and N2O B. Dils1, M. De Mazière1, J. F. Müller1, T. Blumenstock2, M. Buchwitz11, R. de Beek11, P. Demoulin5, P. Duchatelet5, H. Fast3, C. Frankenberg7, A. Gloudemans12, D. Griffith4, N. Jones4, T. Kerzenmacher10, I. Kramer2, E. Mahieu5, J. Mellqvist6, R. L. Mittermeier3, J. Notholt11, C. P. Rinsland13, H. Schrijver12, D. Smale8, A. Strandberg6, A. G. Straume12, W. Stremme9, K. Strong10, R. Sussmann9, J. Taylor10, M. van den Broek12, V. Velazco11, T. Wagner7, T. Warneke11, A. Wiacek10, and S. Wood8 1Belgian Institute for Space Aeronomy, Brussels, Belgium 2Forschungszentrum Karlsruhe and University Karlsruhe, IMK-ASF, Karlsruhe, Germany 3Environment Canada, Downsview, Ontario, Canada 4University of Wollongong, New South Wales, Australia 5Institut d’Astrophysique et de Géophysique, Liège, Belgium 6Chalmers University of Technology, Radio & Space Science, Göteborg, Sweden 7Institute of Environmental Physics, University of Heidelberg, Heidelberg, Germany 8National Institute for Water and Air Research (NIWA), New Zealand 9Forschungszentrum Karlsruhe, IMK-IFU, Garmisch-Partenkirchen, Germany 10Department of Physics, University of Toronto, Toronto, Ontario, Canada 11Institute of Environmental Physics, University of Bremen, FB1, Germany 12Netherlands Institute for Space Research (SRON), Utrecht, The Netherlands 13NASA Langley Research Center, Hampton, VA, USA
Abstract. Total column amounts of CO, CH4, CO2 and N2O retrieved from
SCIAMACHY nadir observations in its near-infrared channels have been
compared to data from a ground-based quasi-global network of
Fourier-transform infrared (FTIR) spectrometers. The SCIAMACHY data
considered here have been produced by three different retrieval algorithms,
WFM-DOAS (version 0.5 for CO and CH4 and version 0.4 for CO2 and
N2O), IMAP-DOAS (version 1.1 and 0.9 (for CO)) and IMLM (version 6.3)
and cover the January to December 2003 time period. Comparisons have been
made for individual data, as well as for monthly averages. To maximize the
number of reliable coincidences that satisfy the temporal and spatial
collocation criteria, the SCIAMACHY data have been compared with a temporal
3rd order polynomial interpolation of the ground-based data. Particular
attention has been given to the question whether SCIAMACHY observes
correctly the seasonal and latitudinal variability of the target species.
The present results indicate that the individual SCIAMACHY data obtained
with the actual versions of the algorithms have been significantly improved,
but that the quality requirements, for estimating emissions on regional
scales, are not yet met. Nevertheless, possible directions for further
algorithm upgrades have been identified which should result in more reliable
data products in a near future.
Citation: Dils, B., De Mazière, M., Müller, J. F., Blumenstock, T., Buchwitz, M., de Beek, R., Demoulin, P., Duchatelet, P., Fast, H., Frankenberg, C., Gloudemans, A., Griffith, D., Jones, N., Kerzenmacher, T., Kramer, I., Mahieu, E., Mellqvist, J., Mittermeier, R. L., Notholt, J., Rinsland, C. P., Schrijver, H., Smale, D., Strandberg, A., Straume, A. G., Stremme, W., Strong, K., Sussmann, R., Taylor, J., van den Broek, M., Velazco, V., Wagner, T., Warneke, T., Wiacek, A., and Wood, S.: Comparisons between SCIAMACHY and ground-based FTIR data for total columns of CO, CH4, CO2 and N2O, Atmos. Chem. Phys., 6, 1953-1976, doi:10.5194/acp-6-1953-2006, 2006.