首页   按字顺浏览 期刊浏览 卷期浏览 A comparison of Doppler and spaced antenna radar techniques for the measurement of turb...
A comparison of Doppler and spaced antenna radar techniques for the measurement of turbulent energy dissipation rates

 

作者: B. G. W. Vandepeer,   W. K. Hocking,  

 

期刊: Geophysical Research Letters  (WILEY Available online 1993)
卷期: Volume 20, issue 1  

页码: 17-20

 

ISSN:0094-8276

 

年代: 1993

 

DOI:10.1029/92GL01116

 

数据来源: WILEY

 

摘要:

There has been concern in the past that spaced antenna radar measurements of energy dissipation rates in the Mesosphere using broad beam arrays may be contaminated by the effects of atmospheric gravity waves. To investigate this possibility, a 1.98 MHz Doppler radar operated by the University of Adelaide was used in two separate configurations; a narrow vertical beam (4.5° half power half width) and 3 smaller spaced antenna systems with broad beams (20° half power half width) were used to simultaneously measure energy dissipation rates in the height region 80 to 100km. The 3 broad beams were also used to determine winds by the spaced antenna method. Although extraction of the energy dissipation rate parameter is a difficult process, temporally and spatially coincident data were obtained enabling some important comparisons to be made. Three years of such data were analysed and the following results noted: (1) the mean energy dissipation rates as measured by the two radars are comparable, (2) the variance of the data as measured by the Doppler radar is larger than that measured by the spaced antenna radar, (3) The spaced antenna radar does not generally over‐estimate energy dissipation rates at moderate and large values, but when turbulence is very weak, it may do so. The degree of over‐estimation is not as serious as has been inferred in the past. However, there is considerable scatter in the short term ratio of measurements using the two methods, which emphasizes the large degree of spatial variability of turbulence strengths in the middle atmos

 

点击下载:  PDF (438KB)



返 回