M. De Mazière et al., HYMN, May 2007 Status of WP4: FTIR measurements M. De Mazière (BIRA-IASB) K. Petersen, T. Warneke, J. Notholt (U. Bremen)

M. De Mazière et al., HYMN, May 2007 Ground-based FTIR network

M. De Mazière et al., HYMN, May 2007 WP4: Observations from ground networks

M. De Mazière et al., HYMN, May 2007 From DoW WP4: Perform solar absorption measurements in the mid-infrared spectral region at the 7 European NDACC stations (28°N to 80°N), throughout the duration of the project, at a minimal frequency of about 1 meas./week And perform measurements at tropical stations during campaigns Optimise the retrieval of CH4 in the mid-infrared spectral region Evaluate the error budget of CH4 and N2O vertical profiles Provide a consistent set of total column densities and vertical profiles of CH4 and N2O for model evaluation and satellite validation Validate and calibrate the SCIAMACHY and IASI satellite measurements

M. De Mazière et al., HYMN, May 2007 Status at KO For CH4 Set of retrieval microwindows defined for profile retrieval  DOF  3  Relative error on tropo- column  10% For N2O 2 Sets of retrieval microwindows defined for profile retrieval  DOF  4.5  Relative error on tropo- column  5 to 10% For both: Consistent timeseries at UFTIR stations (excl. tropical and ship-borne data) BUT: Error budget ? In part. for CH4: accuracy? Cf. uncertainties on spectroscopic params. Lack of data in tropics

M. De Mazière et al., HYMN, May 2007 (To be) done in HYMN Continuation of measurements at the European NDACC sites : ongoing Analysing past data at tropical stations and performing new measurement campaigns in the tropics: ongoing, esp. at Paramaribo and Ile de La Réunion  agreement to perform and report pressure measurements and/or pressure data from weather stations. Optimisation of the total column and profile retrievals of CH 4 in the mid-IR:  Analysis of new microwindow options (all)  CH4 cell measurements (Univ. Bremen and IMK- Karlsruhe) to define spectroscopic parameters  results expected by July 2007  NCEP/ECMWF data: KNMI provides ECMWF data to test sensitivity of retrieval to T-profile

M. De Mazière et al., HYMN, May 2007 (To be) done in HYMN (cont’d)  Retrieval strategy: to be homogenized as much as possible from station to station. Provision of a consistent set of total column densities and vertical profiles of CH 4 and N 2 O for model evaluation and satellite validation.  By September 2007: submission of preliminary historical time series in HYMN database; focus on 2004; if possible, extend from 2003 to 2006  Archived parameters, metadata and data format have been decided: = individual profile data + averaging kernels in HDFv4.3 format, inline with AVDC guidelines Evaluation of the error budget of vertical profile data (CH4 and N2O): while fixing retrieval strategy

M. De Mazière et al., HYMN, May 2007 (To be) done in HYMN (cont’d) Comparisons FTIR –Model:  every group will do the comparison for its own sites!  Model data will be provided in separate files for each site (each day at 12h LT or 10-16h LT mean)  Do the modelers need info as to timing of FTIR measurements ? Comparisons FTIR – satellite  Via model and direct FTIR-satellite  Need fro dry-air column averaged VMR ? Test at tropical stations. Next meeting in October 2007