Applicability of the Planar Fit Technique in Estimating Surface Fluxes over Flat Terrain using Eddy Covariance

DOI JASI Web Site Web Site 2 Citations 35 References

Bibliographic Information

Other Title
  • 渦相関法による平坦地の地表面フラックス推定における平面近似法の適用性

Search this article

Description

The planar fit technique is a coordinate rotation scheme widely used for tower-based eddy covariance measurements. Applicability of this technique was examined with respect to the geometry of the mean stream surface. Analyses based on a 3-year eddy-covariance dataset obtained over flat terrain of a paddy field revealed that the mean streamline was upward at almost all wind directions possibly because of flow distortion by the instruments. Fitting a single plane to the concave stream surface led to miscalculations in the offset and tilt angle of the mean streamline. Consequently, the half-hourly mean vertical wind velocity and streamwise momentum flux demonstrated inconsistent distributions in planar fit coordinates. In contrast, they were consistent under a modified planar fit technique, the sectorial planar fit, in which the mean stream plane was determined at each wind sector with a center angle of 30°. The planar fit technique is not applicable when the mean stream surface is not approximated by a plane. In such cases, the sectorial planar fit can be a practical alternative to the ordinary planar fit.

Journal

Citations (2)*help

See more

References(35)*help

See more

Related Projects

See more

Keywords

Details 詳細情報について

Report a problem

Back to top