In this talk I will present the Lagrangian particle dispersion model FLEXPART and applications of it. FLEXPART calculates Lagrangian trajectories based on grid-scale winds as well as stochastic parametrizations of turbulence and convection. It can also account for radioactive decay, wet and dry deposition, gravitational settling and linear chemistry. The model has an active user community of probably several hundred research groups worldwide and is used operationally at several weather services and at CTBTO.
I will present example applications ranging from the Lagrangian diagnosis of extreme events, climatologies of heat and moisture transport, and will also briefly mention (inverse) modelling of microplastic, greenhouse gases, radioactivity and volcanic ash. Finally, I will present a Lagrangian re-analysis based on ERA5 data. For the re-analysis, in a global-domain-filling mode, 10 million particles move freely in the atmosphere over the ERA5 period and their positions are stored every 3 hours. The re-analysis data can be used to extract Lagrangian information for any point on Earth at any time during the ERA5 period without re-running the model.
Michael Mayer