Forward and backward stochastic Lagrangian trajectory simulation methods are
developed to calculate the footprint and cumulative footprint functions of concentration and
fluxes in the case when the ground surface has an abrupt change of the roughness height. The
statistical characteristics to the stochastic model are extracted numerically from a closure model
we developed for the atmospheric boundary layer. The flux footprint function is perturbed in
comparison with the footprint function for surface without change in properties. The perturbation
depends on the observation level as well as roughness change and distance from the
observation point. It is concluded that the footprint function for horizontally homogeneous surface,
widely used in estimation of sufficient fetch for measurements, can be seriously biased in
many cases of practical importance.
This quarterly published journal presents original articles on the theory and applications of Monte Carlo and Quasi-Monte Carlo methods. Launched in 1995 the journal covers all stochastic numerics topics with emphasis on the theory of Monte Carlo methods and new applications in all branches of science and technology.