FLEXPART (“FLEXible PARTicle dispersion model”) is a Lagrangian transport and dispersion model suitable for the simulation of a large range of atmospheric transport processes. Apart from transport and turbulent diffusion, it is able to simulate dry and wet deposition, decay, linear chemistry; it can be used in forward or backward mode, with defined sources or in a domain-filling setting. It can be used from local to global scale.
FLEXPART is a further development of its predecessor FLEXTRA (“FLEXible TRAjectory model”). Both FLEXTRA and FLEXPART have been open source models since the beginning and, over time have found a large international user community.