The effect of tilt-corrections on fluxes and 3D wind statistics over sloping, forested terrain

As part of the 2004 Carbon in the Mountains Experiment (CME04), three towers were deployed by the NCAR Earth Observing Laboratory (EOL) in a subalpine forest near the University of Colorado (CU) AmeriFlux tower. The towers were located in complex mountainous terrain approximately 10 km east of the Continental Divide below Niwot Ridge, Colorado. One tower is in a relatively open area while the other three towers are in a mixed-conifer subalpine forest. The topography at the site has a slope angle that ranges from 4-7 degrees. Sonic anemometer wind measurements are typically "tilt-corrected" to align the wind vector with the mean streamline (Wilczak, et al. 2001, Sun, 2007). In our study we explore the effect of the tilt-correction on the wind component statistics and sensible heat flux calculations over sloping terrain for different atmospheric stability conditions.

References:

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Sun J. 2007: Tilt corrections over complex terrain and their implication for CO2 transport. Boundary-Layer Meteorology, 124, 143-159.

Wilczak, J.M., S.P. Oncley, and S.A. Stage, 2001: Sonic anemometer tilt correction algorithms, Boundary-Layer Meteorology, 99, 127-150.