A Simple Method to Estimate the Refractive Index Structure Parameter (Cn2) in the Atmosphere

This paper proposes a simple physics-based method for estimating the C-n(2) 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 C-n(2) profile. Using sounding data from Lhasa (Tibet) C-n(2) profiles were estimated using three outer scale models (Thorpe, HMNSP99, and Ellison) and compared with the measured C-n(2) profile. Results show that the Ellison scale method offers better results as a profile estimator than the other two methods. Compared with the measured C-n(2) profile, the average relative error of the Ellison scale method is generally lower than 8%, with a correlation coefficient larger than 0.5.