Year: 2008
Type: conference-paper
Abstract: This paper studies the phenomenon of intermittency in the stable boundary layer with particular emphasis on the energetic coupling between land and atmosphere.The stable boundary layer is modelled with two different minimalistic models, a one-dimensional (height-dependent) model and a bulk model.Turbulence is parameterized using a Richardson number dependent eddy viscosity.The most important ingredient of both models is the treatment of the lower boundary: it is based on a simplified energy balance of a vegetation layer and includes besides radiative cooling an energetic coupling with both the atmosphere and the deep soil.The resulting temperature boundary condition is time-dependent and interacts with the atmospheric dynamics.For a large range of parameters both models display unsteady behaviour where the state of the atmosphere changes between turbulent and laminar (collapsed turbulence).But sustained unsteady behaviour appears only possible when the coupling between vegetation and atmosphere is sufficiently strong.Both models show qualitative comparable behaviour.This provides a strong indication that the surface-atmosphere interaction could play an important role in the occurrence of intermittency in the stable boundary layer.
Institution: Delft University of Technology
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Climate action
Open Access status: green
OpenAlex ID: W1566530583