THE DEPTH OF THE INTERNAL BOUNDARY-LAYER OVER AN URBAN AREA UNDER SEA-BREEZE CONDITIONS

Field data are analyzed in order to study the development of the Thermal Internal Boundary Layer (TIBL) under sea breeze conditions. The measurements were carried out by the National Observatory of Athens (NOA) during ATHens Internal Boundary Layer Experiment (ATHIBLEX) in summer 1989 and 1990. Several formulations found in the literature are tested against the measurements in order to investigate whether they are capable of -predicting the depth of the TIBL. It is found that a slab model including mechanical production of turbulence gives overall good agreement with the measurements. Finally, the concept of local equilibrium is used to explain the discrepancies found between small- and meso-scale observations and models; a formula is proposed which is intended for use over a wide range of downwind fetches.