Measurements of turbulence structure in the daytime convective boundary layer from a ground-based Doppler lidar

We have analyzed measurements of vertical velocity w statistics from 300 m above the surface to the top of the convective boundary layer (CBL) from the NOAA High Resolution Doppler Lidar (HRDL) over a relatively flat and uniform agricultural surface during the Lidars in Flat Terrain (LIFT) Experiment. The temporal resolution of the zenith-pointing lidar was about 1 s, and the range-gate resolution was about 30 m. The vertical cross-sections were used to calculate spectra, turbulence kinetic energy, turbulence dissipation, and higher-moment statistics of w as a function of height with unprecedented vertical resolution throughout most of the CBL. We compare the results with previous formulations based on both measurements and simulations, and discuss the considerable differences, both on an averaged and a case-by-case basis. A major source of case-to-case variability in the spectra and higher-moments statistics is due to differences in the mean structure within the CBL and across the top.