Horizontal-Velocity and Variance Measurements in the Stable Boundary Layer Using Doppler Lidar: Sensitivity to Averaging Procedures
Quantitative data on turbulence variables aloft--above the region of the atmosphere conveniently measured from towers--has been an important but difficult measurement need for advancing understanding and modeling of the stable boundary layer (SBL). Vertical profiles of streamwise velocity variances obtained from NOAA’s High Resolution Doppler Lidar (HRDL), which have been shown to be numerically equivalent to turbulence kinetic energy (TKE) for stable conditions, are a measure of the turbulence in the SBL. In the present study, the mean horizontal wind component U and variance σu2 were computed from HRDL measurements of the line-of-sight (LOS) velocity using a technique described in Banta, et al. (2002). The technique was tested on datasets obtained during the Lamar Low-Level Jet Project (LLLJP) carried out in early September 2003, near the town of Lamar in southeastern Colorado. This paper compares U with mean wind speed obtained from sodar and sonic anemometer measurements. It then describes several series of averaging tests that produced the best correlation between TKE calculated from sonic anemometer data at several tower levels and lidar measurements of horizontal velocity variance σu2. The results show high correlation (0.71-0.97) of the mean U and average wind speed measured by sodar and in-situ instruments, independent of sampling strategies and averaging procedures. Comparison of estimates of variance, on the other hand, proved sensitive to both the spatial and temporal averaging techniques.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 947461
- Report Number(s):
- PNNL-SA-57257; 830403000; TRN: US200909%%93
- Journal Information:
- Journal of Atmospheric and Oceanic Technology, 25(8):1307-1326, Vol. 25, Issue 8
- Country of Publication:
- United States
- Language:
- English
Similar Records
A Case Study of the Weather Research and Forecasting Model Applied to the Joint Urban 2003 Tracer Field Experiment. Part 1. Wind and Turbulence
Field evaluation of remote wind sensing technologies: Shore-based and buoy mounted LIDAR systems