Środowiskowe Seminarium Fizyki Atmosfery

We investigate high-resolution airborne data collected in the course of the Physics of Stratocumulus Top (POST) project. Analysis of 8 different cases of marine stratocumuli, based on ~400 aircraft penetrations across the Entrainment Interfacial Layer (EIL), reveals a fine-layered structure of the cloud top and capping inversion. Despite very high static stability, the inversion and the whole EIL remain turbulent with maximum turbulence intensity just below the cloud top. The thickness of the EIL corresponds to the thickness of the shear layer in the cloud top region, and adapts to the velocity- and buoyancy-jump between the cloud layer and the free troposphere in such a way, that the gradient Richardson Number across EIL sublayers remains critical. Estimates of Ozmidov and Corrsin scales indicate significant anisotropy turbulence in scales governing turbulent transport across the EIL.