This version of FLEXPART includes the following changes and improvements:

1. By leveraging the native vertical coordinates of European Centre for Medium Range Weather Forecasts (ECMWF) Integrated Forecasting System (IFS) instead of interpolating to terrain-following coordinates, we achieved an improvement in trajectory accuracy, leading to a ~8-10 % reduction in conservation errors for semi-conserved quantities like potential vorticity.
2. The shape of aerosol particles is now accounted for in the gravitational settling and dry deposition calculation, increasing the simulation accuracy for non-spherical aerosol particles such as microplastic fibers.
3. Wet deposition has been improved by the introduction of a new below-cloud scheme, a new cloud identification scheme, and by improving the interpolation of precipitation.
4. Functionality from a separate version of FLEXPART, the FLEXPART-CTM model, is implemented, which includes linear chemical reactions.
5. The incorporation of Open Multi-Processing parallelisation makes the model better suited for handling large input data.
6. Users now have the option to run FLEXPART with more flexible particle input data, providing greater adaptability for specific research scenarios (e.g. effective backward simulations corresponding to satellite retrievals).
7. Users can now restart runs from dedicated 'restart files' written at user-defined intervals.
8. We have transformed the particle dump output into NetCDF format, allowing users to selectively choose particle properties and meteorological data along particle trajectories to be written to file.
9. A new user manual and restructuring of the source code into modules will serve as a basis for further development.

This is the release for the version described in the Pisso et al (2019) article in Geoscientific Model Development.

Copyright 1998-2019 (GPLv3)

Contributors: Andreas Stohl, Petra Seibert, A. Frank, Gerhard Wotawa, Caroline Forster, Sabine Eckhardt, John Burkhart, Harald Sodemann, Ignacio Pisso, Espen Sollum, Henrik Grythe, Nina I. Kristiansen, Massimo Cassiani, Delia Arnold, Don Morton, Rona L. Thompson, Christine D. Groot Zwaaftink, Nikolaos Evangeliou, Leopold Haimberger, Stephan Henne, Dominik Brunner, John F. Burkhart, Anne Fouilloux, Jerome Brioude, Anne Philipp.

Please refer as well to: NILU Flexpart Gitlab