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Atmos. Chem. Phys. Discuss., 7, 9319-9365, 2007
www.atmos-chem-phys-discuss.net/7/9319/2007/ doi:10.5194/acpd-7-9319-2007 © Author(s) 2007. This work is licensed under a Creative Commons License. |
Intercomparison of ILAS-II Version 1.4 and Version 2 target parameters with MIPAS-Envisat measurements
1National Institute for Environmental Studies (NIES), Tsukuba, Japan
2Institute of Meteorology and Climate Research (IMK-ASF), Forschungszentrum Karlsruhe and University Karlsruhe, Karlsruhe, Germany
*on leave
Abstract. We compared measurements taken by two satellite-borne instruments, ILAS-II and MIPAS-Envisat, between May and October 2003. Using the coincidence criteria of ±300 km in space and ±12 h in time for H2O, N2O, and CH4 and the coincidence criteria of ±300 km in space and ±6 h in time for ClONO2, O3, and HNO3, a different number of coincidences have been found for the gases. The data were separated into sunrise and sunset measurements, which correspond to Northern and Southern Hemisphere data, respectively. For the sunrise data of ILAS-II, a clear improvement from Version 1.4 to Version 2.1 was observed for H2O, CH4, ClONO2, and O3. For ILAS-II N2O and HNO3 data there were no large differences between the two data sets. In particular, the ILAS-II Version 1.4 data were unrealistically small for H2O, CH4, and O3 and unrealistically large for ClONO2 above 20 km to 30 km. The differences between the two algorithm versions for the sunset data were not as large as for the sunrise data for all gases, and for H2O and CH4. ILAS-II Version 1.4 data fitted even better to the MIPAS-Envisat measurements than Version 2.0.
Citation: Griesfeller, A., von Clarmann, T., Griesfeller, J., Höpfner, M., Milz, M., Nakajima, H., Steck, T., Sugita, T., Tanaka, T., and Yokota, T.: Intercomparison of ILAS-II Version 1.4 and Version 2 target parameters with MIPAS-Envisat measurements, Atmos. Chem. Phys. Discuss., 7, 9319-9365, doi:10.5194/acpd-7-9319-2007, 2007.