Estimation and measurements of optical turbulence over snow

Eddy-covariance and profile measurements over snow were carried out at the 35 m tower in Hefei from Jan 28, 2008 to Feb 1, 2008. A similarity function was presented for the stable atmospheric stratification, and then refractive index structure parameter for the optical turbulence was estimated using eddy-covariance and bulk methods based on the function. Results show that the atmosphere near snow surface was nearly neutral and stable during most of the time in the experiment; with the presented similarity function, the estimate results using the two methods agree well with the measured one; the refractive index structure parameter over the snow cover ranged from 1.9×10-16 to 1×10-14 m-2/3, and exhibited a clear diurnal dependence like that over lawn, ocean and desert.