Determination of Representative Canopy Height of Forests from Aerodynamic Data

HR: 1340h
AN: B33E-1672 [Abstracts]
TI: Determination of Representative Canopy Height of Forests from Aerodynamic Data
AU: * Nakai, T
EM: taro@pop.lowtem.hokudai.ac.jp
AF: CREST, Japan Science and Technology Agancy, 4-1-8, Honcho, Kawaguchi, 332-0012, Japan
AU: * Nakai, T
EM: taro@pop.lowtem.hokudai.ac.jp
AF: Institute of Low Temperature Science, Hokkaido University, N19W8, Kita-ku, Sapporo, 060- 0819, Japan
AU: Sumida, A
EM: asumida@lowtem.hokudai.ac.jp
AF: Institute of Low Temperature Science, Hokkaido University, N19W8, Kita-ku, Sapporo, 060- 0819, Japan
AU: Kodama, Y
EM: kod@pop.lowtem.hokudai.ac.jp
AF: Institute of Low Temperature Science, Hokkaido University, N19W8, Kita-ku, Sapporo, 060- 0819, Japan
AU: Ohta, T
EM: takeshi@agr.nagoya-u.ac.jp
AF: Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
AB: The canopy height is the essential length scale for micrometeorological studies, especially for intersite comparison studies, but there has been a lack of consensus of how to determine it. We proposed the `aerodynamic canopy height’ h_a to provide a universal method of determining representative canopy height, which was originally introduced by Maki (1975) and determined by simple linear regression between zero- plane displacement d and roughness length z₀ (Thom, 1971), without the need for stand inventory data. The applicability of h_a was confirmed in five different forests, including a forest with a complex canopy structure. The linear relationship between d and z₀ was explained by assuming that the logarithmic wind profile above the canopy and the exponential wind profile within the canopy are continuous at canopy height, indicating that h_a is essentially the same as that previously defined by the inflection point of the vertical wind profile (Thomas and Foken, 2007).
DE: 0315 Biosphere/atmosphere interactions (0426, 1610)
DE: 0426 Biosphere/atmosphere interactions (0315)
DE: 0428 Carbon cycling (4806)
DE: 0495 Water/energy interactions (1878)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting