Variability of CN(2) and Wind as Seen by the 50-MHz Radar at WSMR

摘要

The mean vertical profile of the refractivity turbulence structure constant CN2and its variability with season, time of day, and background weather conditions at White Sands Missile Range (WSMR), NM from approximately 5 to 20 km altitude are described. Observations, taken with a very high frequency 5O MHz profiling radar located at WSMR from January 1991 through April 1994, are used to describe the variability of windspeed, vertical wind shear, spectral width, and volume reflectivity calibrated as CN2. CN2 is lognormally distributed, shows very small diurnal and interannual variation at all heights, has maximum value in the troposphere during summer, and shows small seasonal variation in the stratosphere. The typical time between statistically independent observations of CN2 is approximately 2 h. Daily values of CN2 depend strongly on local weather conditions, resulting in a strong correlation of meridional wind direction in the troposphere and indicators of gravity wave activity in the stratosphere. A simple regression model for estimating CN2 is presented.