Abstract
Static pressure fluctuations in the microscale range were measured in a mature deciduous forest. Pressure measurements were taken at the ground and above the canopy, and mean profile data of windspeed were collected from above the canopy to near the forest floor. Time series, spectra, and cross-correlations were calculated under different canopy conditions, and relationships between surface pressure fluctuations and mean windspeeds were determined. High-frequency pressure fluctuations that occur over aerodynamically smoother surfaces do not occur at the forest floor. These surface fluctuations are advected by the wind above the canopy, not that within the trunk space. The shapes of the pressure spectra are affected by changes in windspeed. Comparisons of spectra above and below the canopy also show some effect of the canopy itself on the shape of the pressure spectra.
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Sigmon, J.T., Knoerr, K.R. & Shaughnessy, E.J. Microscale pressure fluctuations in a mature deciduous forest. Boundary-Layer Meteorol 27, 345–358 (1983). https://doi.org/10.1007/BF02033744
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DOI: https://doi.org/10.1007/BF02033744