Acta Geophysica

, Volume 56, Issue 1, pp 194–219 | Cite as

Boundary layer characteristics and turbulent exchange mechanisms in highly complex terrain

  • Mathias W. RotachEmail author
  • Marco Andretta
  • Pierluigi Calanca
  • Andreas P. Weigel
  • Alexandra Weiss


The Mesoscale Alpine Programme’s Riviera project investigated the turbulence structure and related exchange processes in an Alpine valley by combining a detailed experimental campaign with high-resolution numerical modelling. The present contribution reviews published material on the Riviera Valley’s boundary layer structure and discusses new material on the near-surface turbulence structure. The general conclusion of the project is that despite the large spatial variability of turbulence characteristics and the crucial influence of topography at all scales, the physical processes can accurately be understood and modelled. Nevertheless, many of the “text book characteristics” like the interaction between the valley and slope wind systems or the erosion of the nocturnal valley inversion need reconsideration, at least for small non-ideal valleys like the Riviera Valley. The project has identified new areas of research such as post-processing methods for turbulence variables in complex terrain and new approaches for the surface energy balance when advection is non-negligible. The exchange of moisture and heat between the valley atmosphere and the free troposphere is dominated by local “secondary” circulations due to the curvature of the valley axis. Because many curved valleys exist, and operational models still have rather poor resolution, parameterization of these processes may be required.

Key words

MAP complex terrain boundary layer valley wind slope wind turbulent exchange high-resolution numerical modeling turbulence parameterisation 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Andretta, M., A.P. Weigel, and M.W. Rotach (2002), Eddy correlation flux measurements in an alpine valley under different mesoscale circulations, Preprints 10th AMS Conference on Mountain Meteorology, 17–21 June 2002, Park City, UT, 109–111.Google Scholar
  2. Beljaars, A.C.M., and P. Viterbo (1998), Role of the boundary layer in a numerical weather prediction model. In: A.A.M. Holtslag and P.G. Dunkirk (eds.), Proc. Colloquium Clear and Cloudy Boundary Layers, Amsterdam, 26–29 August 1997.Google Scholar
  3. Bougeault, P., P. Binder, A. Buzzi, R. Dirks, R. Houze, J. Kuettner, R.B. Smith, R. Steinacker, and H. Volkert (2001), The MAP special observing period, Bull. Am. Meteorol. Soc. 82, 433–462.CrossRefGoogle Scholar
  4. Buzzi, M., and M.W. Rotach (2006), Gridscale parameterization of topographic effects on radiation, LM User Meeting, Langen, 6–8 March 2006.Google Scholar
  5. Chow, F.T., A.P. Weigel, R.L. Street, M.W. Rotach, and M. Xue (2006), High-resolution large-eddy simulations of flow in a steep Alpine valley. Part I: Methodology, verification, and sensitivity experiments, J. Appl. Meteorol. Clim. 45, 63–86.CrossRefGoogle Scholar
  6. Chow, F.T., R.L. Street, M. Xue, and J.H. Ferziger (2005), Explicit filtering and reconstruction turbulence modeling for large-eddy simulation of neutral boundary layer flow, J. Atmos. Sci. 62, 2058–2077.CrossRefGoogle Scholar
  7. Clements, W.E., J.A. Archuleta, and P.H. Gudiksen (1989), Experimental design for the 1984 ASCOT field study, J. Appl. Meteorol. 28, 405–413.CrossRefGoogle Scholar
  8. Colette, A., F.K. Chow, and R.L. Street (2003), A numerical study of inversion-layer breakup and the effects of topographic shading in idealized valleys, J. Appl. Meteorol. 42, 1255–1272.CrossRefGoogle Scholar
  9. Defant, F. (1951), Local winds. In: T.F. Malone (ed.), Compendium of Meteorology, Amer. Meteor. Soc, Boston, 655–672.Google Scholar
  10. De Bruin, H.A.R., W.M.L. Meijninger, A.-S. Smedman and M. Magnusson (2002), Displaced-beam small aperture scintillometer test. Part I: The WINTEX data set, Bound.-Layer Meteor. 105, 129–148.CrossRefGoogle Scholar
  11. De Franceschi, M., and D. Zardi (2003), Evaluation of cut-off frequency and correction of filter-induced phase lag and attenuation in eddy covariance analysis of turbulence data, Bound.-Layer Meteor. 108, 289–303.CrossRefGoogle Scholar
  12. De Wekker, S.F.J. (2002), Structure and Morphology of the Convective Boundary Layer in Mountainous Terrain, PhD. Thesis, The University of British Columbia, 191 pp., available from the National Library of Canada (microfiches), Ottawa.Google Scholar
  13. De Wekker, S.F.J., D.G. Steyn, J.D. Fast, M.W. Rotach, and S. Zhong (2005), The performance of RAMS in representing the convective boundary layer structure in a very steep valley, Environ. Fluid Mech. 5, 35–62.CrossRefGoogle Scholar
  14. Doran, J.C., J.D. Fast, and J. Horel (2002), The VTMX 2000 campaign, Bull. Am. Meteor. Soc. 83, 537–551.CrossRefGoogle Scholar
  15. Grubisiç, V., L. Armi, J.P. Kuettner, S.J. Haimov, L. Oolman, R.R. Damiani, and B.J. Billings (2006), Atmospheric rotors: Aircraft in situ and cloud radar measurements in T-REX, Preprints AMS 12th Mountain Meteorology Conference, Santa Fe, Amer. Meteor. Soc.Google Scholar
  16. Hasager, C.B., and N.O. Jensen (1999), Surface-flux aggregation in heterogeneous terrain, Quart. J. Roy. Meteor. Soc. 125, 2075–2102.CrossRefGoogle Scholar
  17. Henne, S., M. Furger, S. Nyeki, M. Steinbacher, B. Neininger, S.F.J. De Wekker, J. Dommen, N. Spichtinger, A. Stohl, and A.S.H. Prévôt (2004), Quantification of topographic venting of boundary layer air to the free troposphere, Atmos. Chem. Phys. 4, 497–509.CrossRefGoogle Scholar
  18. Holtslag, A.A.M., and F.T.M. Nieuwstadt (1986), Scaling the Atmospheric Boundary Layer, Bound-Layer Meteor. 36, 201–209.CrossRefGoogle Scholar
  19. Jackson, P.S., and J.R.C. Hunt (1975), Turbulent wind low over a low hill, Quart. J. Roy. Meteor. Soc. 101, 929–955.CrossRefGoogle Scholar
  20. Kadygrov, E., V. Kadygrov, E. Miller, H. Weber, and M.W. Rotach (2001), The thermal structure of the atmospheric boundary layer in an Alpine valley: Results of continuous remote sensing measurements and comparison with radio sonde data. In: W.L. Smith and Yu.M. Timofeyev (eds.), IRS 2000: Current Problems in Atmospheric Radiation, A. Deepak Publishing, Hampton, Virginia, 1097–1101.Google Scholar
  21. Kaimal, J.C., J.C. Wyngaard, Y. Izumi, and O.R. Coté (1972), Spectral characteristics of surface layer turbulence, Quart. J. Roy. Meteor. Soc. 98, 563–589.CrossRefGoogle Scholar
  22. Kolmogorov, A.N. (1941), The local structure of turbulence in incompressible viscous fluid for very large Reynolds numbers, Doklady ANSSSR 30, 301–304 (in Russian).Google Scholar
  23. Lee, X., and X. Hu (2002), Forest-Air fluxes of carbon, water and energy over non-flat terrain, Bound.-Layer Meteor. 103, 277–301.CrossRefGoogle Scholar
  24. Mahrt, L. (1982), Momentum balance of gravity flows, J. Atmos. Sci. 39, 2701–2711.CrossRefGoogle Scholar
  25. Matzinger, N., M. Andretta, E. van Gorsel, R. Vogt, A. Ohmura, and M.W. Rotach (2003), Surface radiation budget in an alpine valley, Quart. J. Roy. Meteor. Soc. 129, 877–895.CrossRefGoogle Scholar
  26. McMillen, R.T. (1988), An eddy correlation technique with extended applicability to non-simple terrain, Bound.-Layer Meteor. 43, 231–245, DOI: 10.1007/BF00128405.CrossRefGoogle Scholar
  27. Moore, C.J. (1986) Frequency response correction for eddy correlation systems, Bound.-Layer Meteor. 37, 17–35.CrossRefGoogle Scholar
  28. Monin, A., and A.M. Obukhov (1954), Basic laws of turbulent mixing in the ground layer of the atmosphere, Trudy Akad. Nauk SSSR 151, 163–187 (in Russian).Google Scholar
  29. Muller, M.D., and D. Scherer (2005), A grid-and subgrid-scale radiation parameterization of topographic effects for mesoscale weather forecast models, Mon. Weather Rev. 133, 6, 1431–1442.CrossRefGoogle Scholar
  30. Neininger, B., W. Fuchs, M. Bäumle, A. Volz-Thomas, A.H.S. Prevot, and J. Dommen (2001), A small aircraft for more than just ozone: Metair’s Dimona after ten years of evolving developments, Proc. 11 th Symp. Meteorol. Observations and Instrumentation, Albuquerque, NM, 14–19 January 2001, 123–128.Google Scholar
  31. Nieuwstadt, F.T.M. (1984), Turbulence structure of the stable nocturnal boundary layer, J. Atmos. Sci. 35, 2202–2216.CrossRefGoogle Scholar
  32. Noppel, H., and F. Fiedler (2002), Mesoscale heat transport over complex terrain by slope winds — A conceptual model and numerical simulations, Bound.-Layer Meteor. 104, 73–97.CrossRefGoogle Scholar
  33. Ohba, R., T. Hara, S. Nakamura, Y. Ohya, and T. Uchida (2002), Gas diffusion over an isolated hill under neutral, stable and unstable conditions, Atmos. Environ. 36, 5697–5707.CrossRefGoogle Scholar
  34. Panofsky, H.A., and J.A. Dutton (1984), Atmospheric Turbulence, John Wiley and Sons, New York, 397 pp.Google Scholar
  35. Princevac, M., J.C.R. Hunt, and H.J.S. Fernando (2007), Steady katabatic winds over long slopes in wide valleys, J. Atmos. Sci. (in press).Google Scholar
  36. Randall, D.A. (2001), Representing the turbulent boundary layer in global atmospheric models, EGS, XXVI General Assembly, Nice, France, 26–30 March 2001.Google Scholar
  37. Raupach, M.R., R.A. Antonia, and S. Rajagopalan (1991), Rough-wall turbulent boundary layers, Appl. Mech. Rev. 44, 1–25.CrossRefGoogle Scholar
  38. Raupach, M.R., J.J. Finnigan, and Y. Brunet (1996), Coherent eddies and turbulence in vegetation canopies: the mixing-layer analogy, Bound.-Layer Meteor. 78, 351–382.CrossRefGoogle Scholar
  39. Rotach, M.W., and D. Zardi (2007), On the boundary layer structure over highly complex terrain: key findings from map, Quart. J. Roy. Meteor. Soc. 133, 625, 937–948.CrossRefGoogle Scholar
  40. Rotach, M.W., P. Calanca, P. Graziani, J. Gurtz, D.G. Steyn, R. Vogt, M. Andretta, A. Christen, S. Cieslik, R. Connolly, S.F.J. De Wekker, S. Galmarini, E.N. Kadygrov, V. Kadygrov, E. Miller, B. Neininger, M. Rucker, E. van Gorsel, H. Weber, A. Weiss, and M. Zappa (2004), Turbulence structure and exchange processes in an Alpine Valley: The Riviera project, Bull. Am. Meteor. Soc. 85, 9, 1367–1385.CrossRefGoogle Scholar
  41. Rotach, M.W., R. Vogt; C. Bernhofer, E. Batchvarova, A. Christen, A. Clappier, B. Feddersen, S.-E. Gryning, H. Mayer, V. Mitev, T.R. Oke, E. Parlow, H. Richner, M. Roth, Y.-A. Roulet, D. Ruffieux, J. Salmond, M. Schatzmann, and J.A. Voogt (2005), BUBBLE — an Urban Boundary Layer Meteorology Project, Theor. Appl. Climatol. 81 (3–4), 231–261, DOI: 10.1007/s00704-004-0117-9.CrossRefGoogle Scholar
  42. Schotanus, P., F.T.M. Nieuwstadt, and H.A.R. De Bruin (1983), Temperature measurement with a sonic anemometer and its application to heat and moisture fluxes, Bound.-Layer Meteor. 26, 81–93.CrossRefGoogle Scholar
  43. Savelyev, S.A., and P.A. Taylor (2005), Internal boundary layers: I. Height formulae for neutral and diabatic flows, Bound.-Layer Meteor. 115, 1–25.CrossRefGoogle Scholar
  44. Taylor, P.A., and H.W. Teunissen (1987), The Askervein project: overview and background data, Bound.-Layer Meteor. 39, 15–39.CrossRefGoogle Scholar
  45. Van Dijk, A., W. Kohsiek, and H.A.R. DeBruin (2003), Oxygen sensitivity of krypton and Lyman-alpha hygrometers, J. Atmos. Oceanic Tech. 20, 143–151.CrossRefGoogle Scholar
  46. Van Gorsel, E., A. Christen, C. Feigenwinter, E. Parlow, and R. Vogt (2002), Daytime turbulence statistics above a steep forested slope, Bound.-Layer Meteor. 109, 311–329.CrossRefGoogle Scholar
  47. Webb, E.K., G.I. Pearman, and R. Leuning (1980), Correction of flux measurements for density effects due to heat and water vapour transfer, Quart. J. Roy. Meteor. Soc. 106, 85–100.CrossRefGoogle Scholar
  48. Weigel, A.P., and M.W. Rotach (2004), Flow structure and turbulence characteristics of the daytime atmosphere in a steep and narrow Alpine valley, Quart. J. Roy. Meteor. Soc. 130, 2605–2627.CrossRefGoogle Scholar
  49. Weigel, A.P., F.T. Chow, M.W. Rotach, R.L. Street, and M. Xue (2006), High-resolution large-eddy simulations of flow in a steep Alpine valley. Part II: Flow structure and heat budgets, J. Appl. Meteorol. Clim. 45, 87–107.CrossRefGoogle Scholar
  50. Weigel, A.P., F.K. Chow and M.W. Rotach (2007a), On the nature of turbulent kinetic energy in a steep and narrow Alpine valley, Bound.-Layer Meteor. 123, 1, 177–199, DOI: 10.1007/s10546-006-9142-9.CrossRefGoogle Scholar
  51. Weigel, A.P., F.K. Chow, and M.W. Rotach (2007b), The effect of mountainous topography on moisture exchange between the “surface” and the free atmosphere, Bound.-Layer Meteor. 125, 2, 227–244, DOI: 10.1007/s10546-006-9120-2.CrossRefGoogle Scholar
  52. Weiss, A. (2002), Determination of stratification and turbulence of the atmospheric surface layer for different types of terrain by optical scintillometry, PhD Thesis, Swiss Federal Institute of Technology, Dissertation #14514, available from:, 157 pp.Google Scholar
  53. Weiss, A., M. Hennes and M.W. Rotach (2001), Derivation of refractive index-and temperature gradients from optical scintillometry for the correction of atmospheric induced problems in highly precise geodetic measurements, Surv. Geophys. 22, 589–596.CrossRefGoogle Scholar
  54. Willis, G.E., and J.W. Deardorff (1974), A laboratory model of the unstable planetary boundary layer, J. Atmos. Sci. 31, 1297–1307.CrossRefGoogle Scholar
  55. Whiteman, C.D. (1982), Breakup of temperature inversions in deep mountain valleys: Part I. Observations, J. Appl. Meteor. 21, 270–289.CrossRefGoogle Scholar
  56. Whiteman, C.D. (2000), Mountain Meteorology. Fundamentals and Applications, Oxford University Press, NewYork-Oxford.Google Scholar
  57. Whiteman, C.D., S.W. Hoch, M. Hanhnenberger, and S. Zhong (2007), METCRAX 2006 — First results from the Meteor Crater experiment, Preprints 29 th Int. Conf. Alpine Meteor., Chambery, France, 4–8 June 2007, 93–97.Google Scholar
  58. Wilczak, J.M., S.P. Oncley, and S.A. Stage (1999), Sonic anemometer tilt correction algorithms, Bound.-Layer Meteor. 99, 127–150.CrossRefGoogle Scholar
  59. Zappa, M., and J. Gurtz (2003), Simulation of soil moisture and evapotranspiration in a soil profile during the 1999 MAP-Riviera Campaign, Hydrol. Earth Syst. Sc. 7, 903–919.CrossRefGoogle Scholar

Copyright information

© Institute of Geophysics, Polish Academy of Sciences 2008

Authors and Affiliations

  • Mathias W. Rotach
    • 1
    Email author
  • Marco Andretta
    • 2
  • Pierluigi Calanca
    • 3
  • Andreas P. Weigel
    • 1
  • Alexandra Weiss
    • 4
  1. 1.Federal Office for Meteorology and ClimatologyMeteoSwissZurichSwitzerland
  2. 2.Department for the Environment, Canton TicinoBellinzonaSwitzerland
  3. 3.ART ReckenholzZürichSwitzerland
  4. 4.British Antarctic SurveyCambridgeUK

Personalised recommendations