Lagrangian Model Output at Empa







FLEXTRA trajectories available at Empa are based on 3D winds of ECMWF similar to Lagranto. FLEXTRA does not use the vertical winds provided by ECMWF directly but uses its own field calculated from the divergence of the horizontal wind components.


Four-hourly trajectories based on 6-hourly ECMWF analyses at 1° x 1° resolution and 60 vertical levels (90 since February 2007) are calculated routinely since 12 June 2006 for a large number of stations given here. Additional trajectory files are available back to 2002 but only for a few selected periods.

The interactive Flextra output browser is available via the GAW website.

Global 1° x 1° x 60 levels ECMWF meteorological input files in GRIB format are available completely since January 2001. The same files are also used by Flexpart. Thus, Flextra (and Flexpart) calculations can be performed rather quickly for any time and location since 2001. Due to the large amount of data not all files are stored on the local disk on lin3a134 anymore. These files are, however, still available from the remote4/ disk and are additionally backuped on tape.

Higher resolution ECMWF input fields with approx. 25 km x 25 km horizontal resolution for the European domain are routinely retrieved since the end of March 2007.

Analysis tools

  • Reading data:
  • Plotting:
  • Reading data: /home/brd134/IDL/hiphop/ on Linux or G:\134 Themen\Modellierung\brd\hiphop\ on Windows
  • Plotting:


  • Analysis trajectories: /remote0/daily_trajek/ecmwf_traj/flextra
  • PNG images: /remote0/daily_trajek/ecmwf_traj/flextra
  • Google Earth overlays: /remote0/daily_trajek/ecmwf_traj/flextra
  • ECMWF GRIB data for Flextra: /remote4/ecmwf_backup