Dry deposition modelling in a Lagrangian dispersion model

Revisions to the dry deposition scheme in the Lagrangian dispersion model, NAME, are described. Improvements are made for situations where material is not well mixed within the boundary layer and for sedimenting heavy particles. The revised scheme overcomes problems of computational noise, common in Lagrangian dispersion models, with a manageable or no increase to the computational cost. The result is a scheme that is well suited to all situations and that has better interaction between the advection, deposition and sedimentation.