Turbulent fluxes over inhomogeneous landscape

Mesoscale surface turbulent fluxes over a complex terrain surrounded by oceans have been investigated using a 3-D numerical mesoscale model, under conditions with and without synoptic flows. The study indicated that under synoptically calm condition, the allocation and intensity of mesoscale surface turbulent fluxes (MSTFs) were greatly impacted by the thermally forced mesoscale circulation (TFMC) over mesoscale heterogeneous landscape. The maximum values of sensible (H_s) and latent (LE) heat fluxes were located over the convergent zones and considerably impacted by the soil wetness (M), but did not depend strongly on the atmospheric background thermal stability (β₀). The simulated results suggested that the sensible heat flux was closely proportional to the square of wind speed in the surface layer. By the action of synoptic flow, the allocation of LE was shifted to downwind, its intensity increased. This study was supported by Institute of Atmospheric Physics (IFA-CNR) at Roma, Italy.