Tuesday, 13 January 2009: 1:30 PM
Doppler lidar measurements of higher-order vertical velocity statistics in the convective boundary layer
Room 122A (Phoenix Convention Center)
We utilized a Doppler lidar to measure second-, third-, and fourth-order statistics of vertical velocity, w, from 390 m above the surface to the top of the daytime convective boundary layer (CBL). The High Resolution 2 μm wavelength Doppler lidar (HRDLS) developed by the NOAA Environmental Technology Laboratory was used to detect the mean radial velocity of aerosol particles. It operated continuously during daytime in the zenith-pointing mode for several days in summer 1996 during the Lidars in Flat Terrain experiment over level farmland in central Illinois. 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 w statistics as a function of height with unprecedented vertical resolution throughout most of the CBL. We compare the observed statistics with previous formulations based on both measurements and simulations, and discuss the differences, both on an averaged and a case-by-case basis.