Errors of dispersions of sea surface slopes measured by means of the spacecraft-mounted lidars are analyzed. Errors caused by deviations of the real wave field from the Gaussian isotropic surface are considered. It is shown that the unaccounted deviations of slope distributions from the Gaussian lead to a systematic decreasing of the calculated slope dispersions values about 11-14%. It is shown that the effect of slopes anisotropy on their dispersions calculation upon the data of spacecraft vertical laser sounding can be neglected.
$^1$Department of Physics of Sea and Inland Water, Faculty of Physics, M.V. Lomonosov Moscow State University. Moscow, 119991, Russia
$^2$Marine Hydrophysical Institute, Russian Academy of Sciences. Sevastopol, 299001, Russia