Obtaining Eddy Fluxes for Non-Homogeneous Environment Using Wavelet Cospectra.

Sandra J. Cardon

UW Department of Atmospheric Science

This is a MS thesis defense

Abstract:

Project FLOSS (Fluxes Over Snow Surfaces) was conducted in February and March, 2003 in the North Park mountain basin in northern Colorado.  The University of Wyoming King Air research aircraft, a 34-m ISFF tower, and two 2-m towers located in areas of different vegetation were employed.  The aircraft data were collected in repeated, low-level passes with every sixth pass followed by an aircraft sounding, while the towers sampled continuously.  Intermittent turbulence was often present as a result of mesoscale circulations, varying terrain, snow cover, vegetation, and stability.  Wavelet analysis was used to calculate eddy fluxes, which were compared to eddy covariance fluxes.  Soundings and comparison plots between the King Air and the towers were created to analyze the vertical structure of the boundary layer.  Time traces and contour plots for the King Air were created using both the eddy covariance and the wavelet techniques, with and without various types of smoothing.  In addition, pass-averaged flux profiles for the King Air were calculated using the wavelet technique.  Using a case study approach, all the plots were analyzed to study how the boundary layer reacted to various types of heterogeneity.