Boundary-Layer Meteorology

, Volume 97, Issue 1, pp 137–166

Footprint Analysis For Measurements Over A Heterogeneous Forest

  • Ü Rannik
  • M. Aubinet
  • O. Kurbanmuradov
  • K. K. Sabelfeld
  • T. Markkanen
  • T. Vesala
Article

DOI: 10.1023/A:1002702810929

Cite this article as:
Rannik, Ü., Aubinet, M., Kurbanmuradov, O. et al. Boundary-Layer Meteorology (2000) 97: 137. doi:10.1023/A:1002702810929

Abstract

The air flow and vertical distribution of sources/sinks inside aforest canopy have been taken into accountin the analysis of the contribution of sources/sinks to measured fluxes and concentrations above a forest. Thestochastic estimators for concentrations and fluxes are described and their evaluation is performed by simulationof an ensemble of fluid parcel trajectories. The influence of the forest canopy on the footprint is important forobservation levels up to a few times the forest height. The influence of along-wind turbulent diffusion, whichanalytical atmospheric surface layer (ASL) footprint models do not account for, is significant even at higherlevels. The footprint analysis has been performed to deduce the Douglas fir canopy carbon dioxide uptake from eddycovariance flux measurements above a mixed Douglas fir–beech forest during the pre-leaf periods of the beech.The scatter in the results indicates that such an analysis is limited, presumably due to horizontal inhomogenetiesin flow statistics, which were not included in trajectory simulation. The analysis, however, is useful for theestimation of the qualitative effect of the forest canopy on the footprint function.

Concentrations and fluxesDouglas firFootprintsForest canopyLagrangian trajectory simulationStochastic estimators

Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Ü Rannik
    • 1
  • M. Aubinet
    • 2
  • O. Kurbanmuradov
    • 3
  • K. K. Sabelfeld
    • 4
  • T. Markkanen
    • 1
  • T. Vesala
    • 1
  1. 1.Department of PhysicsUniversity of HelsinkiHelsinkiFinland
  2. 2.Faculte des Sciences Agronomiques des GemblouxGemblouxBelgium
  3. 3.Scientific Technical Center ClimateAshkhabadTurkmenistan
  4. 4.Institute of Computational Mathematics and Mathematical GeophysicsNovosibirskRussia