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Atmospheric Boundary Layers

Nature, Theory and Applications to Environmental Modelling and Security

  • Alexander Baklanov
  • Branko Grisogono

Table of contents

  1. Front Matter
    Pages I-V
  2. Antônio G. O. Goulart, Gervásio A. Degrazia, Otávio C. Acevedo, Domenico Anfossi
    Pages 123-131
  3. Vladimir N. Kudryavtsev, Vladimir K. Makin
    Pages 133-147
  4. Peter A. Taylor, P.-Y. Li, Diane V. Michelangeli, Jagruti Pathak, Wensong Weng
    Pages 149-172
  5. Andrey A. Grachev, Edgar L Andreas, Christopher W. Fairall, Peter S. Guest, P. Ola G. Persson
    Pages 173-185
  6. Leena Järvi, Ari-Juhani Punkka, David M. Schultz, Tuukka Petäjä, Harri Hohti, Janne Rinne et al.
    Pages 187-203
  7. A. A. M. Holtslag, G. J. Steeneveld, B. J. H. van de Wiel
    Pages 205-220
  8. Massimiliano Burlando, Emilia Georgieva, Corrado F. Ratto
    Pages 233-241
  9. Back Matter
    Pages 242-242

About this book

Introduction

Most of practically-used turbulence closure models are based on the concept of downgra- ent transport. Accordingly the models express turbulent uxes of momentum and scalars as products of the mean gradient of the transported property and the corresponding turbulent transport coef cient (eddy viscosity, K , heat conductivity, K , or diffusivity, K ). Fol- M H D lowing Kolmogorov (1941), turbulent transport coef cients are taken to be proportional to the turbulent velocity scale, u , and length scale, l : T T K ? K ? K ? u l . (1) M H D T T 2 Usually u is identi ed with the turbulent kinetic energy (TKE) per unit mass, E ,and K T is calculated from the TKE budget equation using the Kolmogorov closure for the TKE dissipation rate: ? ? E /t , (2) K K T where t ? l /u is the turbulent dissipation time scale. This approach is justi ed when it T T T is applied to neutral stability ows, where l can be taken to be proportional to the distance T from the nearest wall. However, this method encounters dif culties in strati ed ows (both stable and uns- ble). The turbulent Prandtl number Pr = K /K exhibits essential dependence on the T M H strati cation and cannot be considered as constant.

Keywords

Atmospheric turbulence Coriolis effect Emergency preparedness Environmental security Geoinformationssysteme ITC Meteorology PBL parameterisations in climate Planetary Boundary Layer (PBL) Topography Weather and air quality modelling Wind moisture temperature

Editors and affiliations

  • Alexander Baklanov
    • 1
  • Branko Grisogono
    • 2
  1. 1.Danish Meteorological InstituteCopenhagenDenmark
  2. 2.Department of GeophysicsUniversity of ZagrebZagrebCroatia

Bibliographic information