L-moments reveal the scales of momentum transport in dense canopy flows

The MATLAB data files (.mat) contain the U (streamwsie), V (cross-stream), and W (vertical) velocity components after carrying out double coordinate rotation. The fluctuations can be computed through either linear detrending or simply by removing the mean. The RSL datafiles are GOAMAZON_NN_data.mat (GoAmazon) and DF_NN_data.mat (Duke Forest). The ASL datafile is SLTEST_NN_Data.mat (SLTEST). For the GoAmazon and SLTEST datasets, z_AMA and z_h indicate the measurement heights. The lowest height is indicated by index 1 while the topmost height by index 9. 

The code DurPN_fast.m can be used to compute the N_p statistics either for u or Delta u signals. The code momentum_quadrant.m can be used to compute the N_p statistics separately for each of the four different quadrants. The codes LegendreShiftPoly.m and lmom.m need to be used together to estimate the L-moments.

For carrying out the wavelet coherence analysis, the following commands are useful:

[wavew_ref,period,scale,~]=wavelet(w_ref,0.05,1,0.25,0.1,-1,'MORLET',6);

[wavew,~,~,~]=wavelet(w,0.05,1,0.25,0.1,-1,'MORLET',6);

where w_ref is the vertical velocity signal at canopy top and w is the signal at any other height.

To generate the wavelet cross scalogram for a particular 30-min run, one can use:

w1=squeeze(squeeze(w(:,1,10)));

u1=squeeze(squeeze(u(:,1,10)));

wtc(u1,w1,'MonteCarloCount',0,'ArrowDensity',[50 50])

The wavelet codes are taken from: 

Grinsted, A., Moore, J. C., & Jevrejeva, S. (2004). Application of the cross wavelet transform and wavelet coherence to geophysical time series. Nonlinear processes in geophysics, 11(5/6), 561-566.

Please contact [e-mail] for any questions.