Theoretical and Applied Climatology

, Volume 87, Issue 1–4, pp 201–211 | Cite as

Water vapour flux profiles in the convective boundary layer

  • H. Linné
  • B. Hennemuth
  • J. Bösenberg
  • K. Ertel
Article

Summary

Water vapour flux profiles in the atmospheric boundary layer have been derived from measurements of water vapour density fluctuations by a ground-based Differential Absorption Lidar (DIAL) and of vertical wind fluctuations by a ground-based Doppler lidar. The data were collected during the field experiment LITFASS-2003 in May/June 2003 in the area of Lindenberg, Germany. The eddy-correlation method was applied, and error estimates of ±50 W/m2 for latent heat flux were found. Since the sampling error dominates the overall measurement accuracy, time intervals between 60 and 120 min were required for a reliable flux calculation, depending on wind speed. Rather large errors may occur with low wind speed because the diurnal cycle restricts the useful interval length. In the lower height range, these measurements are compared with DIAL/radar-RASS fluxes. The agreement is good when comparing covariance and error values. The lidar flux profiles are well complemented by tower measurements at 50 and 90 m above ground and by area-averaged near surface fluxes from a network of micrometeorological stations. Water vapour flux profiles in the convective boundary layer exhibit different structures mainly depending on the magnitude of the entrainment flux. In situations with dry air above the boundary layer a positive entrainment flux is observed which can even exceed the surface flux. Flux profiles which linearly increase from the surface to the top of the boundary layer are observed as well as profiles which decrease in the lower part and increase in the upper part of the boundary layer. In situations with humid air above the boundary layer the entrainment flux is about zero in the upper part of the boundary layer and the profiles in most cases show a linear decrease.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Bange, J, Beyrich, F, Engelbart, D 2002Airborne measurements of turbulent fluxes during LITFASS-98: Comparison with ground measurements and remote sensing in a case studyTheor Appl Climatol733551CrossRefGoogle Scholar
  2. Bange, J, Roth, R 1999Helicopter-borne flux measurements in the nocturnal boundary layer over land – a case studyBound-Layer Meteorol92295325CrossRefGoogle Scholar
  3. Beyrich F (2004) Verdunstung über einer heterogenen Landoberfläche, das LITFASS-2003 Experiment, ein Bericht. Technical report, Deutscher Wetterdienst Forschung und Entwicklung, Arbeitsergebnisse Nr. 79, Offenbach, GermanyGoogle Scholar
  4. Bösenberg, J 1998Ground-based differential absorption lidar for water-vapor and temperature profiling: methodologyAppl Optics3738453860Google Scholar
  5. Bösenberg, J 2005

    Differential absorption lidar for water vapor and temperature profiling

    Weitkamp, C eds. Lidar-range-resolved optical remote sensing of the atmosphereSpringerNew York213240
    Google Scholar
  6. Bösenberg, J, Linné, H 2002Laser remote sensing of the planetary boundary layerMeteorol Z11233240CrossRefGoogle Scholar
  7. Cleugh, H, Grimmond, C 2001Modelling regional scale surface energy exchanges and CBL growth in a heterogeneous, urban-rural landscapeBound-Layer Meteorol98131CrossRefGoogle Scholar
  8. Ertel K (2004) Application and development of water vapor DIAL systems, Dissertation Univ. Hamburg, http://www.sub.uni-hamburg.de/opus/volltexte/2004/2027/
  9. Giez, A, Ehret, G, Schwiesow, RL, Davies, KJ, Lenschow, DH 1999Water vapor flux measurements from ground-based vertically pointed water vapor differential absorption and Doppler LidarsJ Atmos Oceanic Technol16237250CrossRefGoogle Scholar
  10. Hennemuth B, Bange J, Zittel P (2004) Bestimmung des Feuchteflusses in der Grenzschicht über heterogenem Gelände mit bodengebundener Fernerkundung und Helipod. In DACH-Meteorologentagung 2004, Karlruhe, Germany. Dtsch. Meteorol. GesGoogle Scholar
  11. Hirsch, L, Peters, G 1998Abilities and limitations of a radar-RASS wind profiler for the measurement of momentum flux in the planetary boundary layerMeteorol Z NF7336344Google Scholar
  12. Isaac, PR, Mcaneney, J, Leuning, R, Hacker, JM 2004Comparison of aircraft and ground-based flux measurements during oasis95Bound-Layer Meteorol1103967CrossRefGoogle Scholar
  13. Katul, G, Hsieh, CI, Bowling, D, Clark, K, Shurpali, N, Turnipseed, A, Albertson, J, Tu, K, Hollinger, D, Evans, B, Offerle, B, Anderson, D, Ellsworth, D, Vogel, C, Oren, R 1999Spatial variability of turbulent fluxes in the roughness sublayer of an even-aged pine forestBound-Layer Meteorol93128CrossRefGoogle Scholar
  14. Lehmann S (2001) Ein Heterodyn-DIAL-System für die simultane Messung von Wasserdampf und Vertikalwind: Aufbau und Erprobung. Technical report, PhD thesis, Universität Hamburg, Hamburg, GermanyGoogle Scholar
  15. Lenschow, DH, Mann, J, Kristensen, L 1994How long is long enough when measuring fluxes and other turbulence statistics?J Atmos Oceanic Technol11661673CrossRefGoogle Scholar
  16. Lenschow, DH, Stankov, B 1986Length scales in the convective boundary layerJ Atmos Sci4311981209CrossRefGoogle Scholar
  17. Linné H, Bösenberg J (2003) Heterodyne lidar – a tool to investigate dynamic processes in the lower troposphere. In Proc. Sixth Int. Symposium on Tropospheric Profiling, Needs and Technologies, Leipzig, GermanyGoogle Scholar
  18. Mahrt, L 1976Mixed layer moisture structureMon Wea Rev10414031407CrossRefGoogle Scholar
  19. Mengelkamp H.-T. and the EVA-GRIPS-Team (2004) Eva-grips: Regional evaporation at grid and pixel scale over heterogeneous land surfaces. In Fourth Study Conference on BALTEX, Gudhjem, Denmark. International BALTEX Secretariat PublicationGoogle Scholar
  20. Parlange, M, Eichinger, W, Albertson, J 1995Regional scale evaporation and the atmospheric boundary layerRev Geophys3399124CrossRefGoogle Scholar
  21. Rao, MP, Casadio, S, Fiocco, G, Cacciani, M, Sarra, AD, Fua, D, Castracane, P 2002Estimation of atmospheric water vapour flux profiles in the nocturnal unstable urban boundary layer with doppler sodar and raman lidarBound-Layer Meteorol1023962CrossRefGoogle Scholar
  22. Senff, C, Bösenberg, J, Peters, G 1994Measurement of water vapor flux profiles in the convective boundary layer with lidar and radar-RASSJ Atmos Oceanic Technol118593CrossRefGoogle Scholar
  23. Strunin, MA, Hiyama, T, Asanuma, J, Ohata, T 2004Aircraft observations of the development of thermal internal boundary layers and scaling of the convective boundary layer over non-homogeneous land surfacesBound-Layer Meteorol111491522CrossRefGoogle Scholar
  24. Stull, R 1988An introduction to boundary layer meteorologyKluwer Academic PublisherDordrechtGoogle Scholar
  25. Wulfmeyer, V 1998Ground-based differential absorption lidar for water-vapor and temperature profiling: development and specifications of a high-performance laser transmitterAppl Optics3738043824CrossRefGoogle Scholar
  26. Wulfmeyer, V 1999Investigation of turbulent processes in the lower troposphere with water vapor DIAL and radar-RASSJ Atmos Sci5610551076CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • H. Linné
    • 1
  • B. Hennemuth
    • 1
  • J. Bösenberg
    • 1
  • K. Ertel
    • 1
    • 2
  1. 1.Max-Planck-Institute for MeteorologyHamburgGermany
  2. 2.Central Laser Facility, CCLRC Rutherford Appleton LaboratoryChiltonUnited Kingdom

Personalised recommendations