Evidence of dynamical coupling between the residual layer and the developing convective boundary layer
Résumé
The diurnal cycle of the atmospheric boundary layer (ABL) hasbeen documented on 8 August 1998 in the framework of the Étude et Simulation de la QUalité de l'air en Ile-de-France (ESQUIF) experiment that took place in the Paris area. The ABL structure was documented by means of a ground-based lidar, surface meteorological stations and soundings. The interaction between the residual layer and the convective boundary layer is investigated using the collected data as well as mesoscale modelling. As opposed to the generally accepted concept, we find evidence of entrainment at the top ofthe residual layer. High temporal simulations of the 8 August 1998 casemade with the mesoscale atmospheric model Meso-NH also show evidenceof mixing at the top of the residual layer (RL). This mixing is believed to be related to the presence of convective (gravity) waves in the RL.