Vertical transports of energy and trace gases at anchor stations and their spatial and temporal extrapolation under complex natural conditions (VERTIKO) - structure of turbulent fluxes under inhomogeneous surface conditions (STINHO) - simulation of boundary layer turbulence
Responsible: Michael Schröter
Project type: ​BMBF project (the sub-project STINHO belongs to the joint project VERTIKO which is part of the framework programme AFO2000)
Duration: 01/06/2001 - 31/03/2004

Main Homepage of the joint project: ​VERTIKO
Webpage of the sub-project of our institute: ​STINHO

The sub-project STINHO (STruktur des turbulenten Transports über INHOmogener Unterlage) is part of the cooperative project VERTIKO (VERTIkaltransporte von Energie und Spurenstoffen an Ankerstationen unter KOmplexen natürlichen Bedingungen). STINHO consists of 3 parts. The experimental investigations (part 1, ​Acoustic Research Group at LIM) about an inhomogeneous surface with acoustical and optical methods provide near surface averaged values of parameters which are relevant for part 2. Part 2 - which is handles in this working group - deals with the high resolution simulation of the near-surface boundary layer above inhomogeneous terrain by means of the parallelized large-eddy simulation model PALM. In addition to the near-surface experiment and to provide information on the real boundary layer structure to initialize the LES the airborne turbulent measurement system ​HELIPOD is used (part 3).

The physical description of the energy budget variations unter turbulent flow conditions above homogeneous surfaces is possible using one-dimensional models and/or micrometeorological measuring techniques, which determine the energy exchange processes considering only the height above the underlying surface. Such a procedure does not consider the horizontal energy fluxes, which must exist between different types of the surface in heterogeneous tarrain. Currently accepted parameterizations for the turbulent transport of energy only consider the vertical direction neglecting horizontal energy fluxes.

The project achieves a better understanding of the turbulent energy fluxes inside the atmospheric boundary layer, because these fluxes consist of horizontal and vertical components especially visibel in experiments and simulations unter inhomogeneous flow conditions near a heterogeneous surface. Project results will contribute to an improvement of the parameterizations of energy fluxes over heterogeneous terrain for the use in large scale model.