Numerical Simulation of Canopy Flows

1 Introduction.- 2 Distribution of Meteorological Variables in Forest Canopies.- 2.1 Forest Structure and Utilization.- 2.2 Variation of Meteorological Parameters Within a Stand.- 2.2.1 Radiation.- 2.2.2 Temperature.- 2.2.3 Humidity.- 2.2.4 Wind.- 2.3 Methods of Investigation.- 2.3.1 Field Measurements.- 2.3.2 Wind Tunnel Experiments.- 2.3.3 Analytic Description and Numerical Models.- 3 Air Flow Around and Through Individual Trees.- 3.1 The Numerical Model.- 3.1.1 The System of Equations.- 3.1.2 Boundary Values and Initial Conditions.- 3.1.3 Discretization and Numerical Solution.- 3.1.4 Parameterization of the Stand in the Model.- 3.2 Investigations on Single Trees.- 3.2.1 The Reference Run.- 3.2.2 Variation of Meteorological Input Parameters.- 3.2.3 Variations in Shape of the Individual Tree.- 3.2.4 Dispersion of Air Pollutants Around an Isolated Tree.- 3.3 Studies on Groups of Trees.- 3.4 Investigations of Wind Shelter Hedges.- 4 Air Flow Through and Above Stands.- 4.1 Improvement of the Numerical Model.- 4.2 Investigations in a Horizontally Homogeneous Stand.- 4.2.1 Determination of the Optimum Drag Coefficient.- 4.2.2 Influence of Stand Parameters on Temperature, Humidity, Wind and Turbulence.- 4.3 Investigations in a Horizontally Inhomogeneous Stand.- 4.3.1 The Influence of Deforestation Around the Western Runway of Frankfurt Airport.- 4.3.2 Effects of Complete Deforestation of the Finkenbach Valley (Odenwald) on the Local Climate.- 5 Concluding Remarks.- References.- Symbols.