A simple method to estimate the refractive index structure parameter (Cn2 ) in the atmosphere

Abstract

This paper proposes a simple physics-based method for estimating the Cn2 profile in the lower atmosphere, using the Ellison scale as a measure of the outer turbulence scale. The new approach only Requires the temperature profile as an input to obtain the profile of the outer turbulence scale, followed by the Cn2 profile. Using sounding data from Lhasa (Tibet) Cn2 profiles were estimated using three outer scale models (Thorpe, HMNSP99, and Ellison) and compared with the measured Cn2 profile. Results show that the Ellison scale method offers better results as a profile estimator than the other two methods. Compared with the measured Cn2 profile, the average relative error of the Ellison scale method is generally lower than 8%, with a correlation coefficient larger than 0.5.