Ground-Level Atmospheric Turbulence in the Sayan Solar Observatory in Summer 2023

Estimating the influence of atmospheric turbulence on the quality of astronomical images requires appropriate investigations at the sites of observatories. The results of long-term measurements of the atmospheric turbulence characteristics in the Sayan Solar Observatory (SSO) of the Institute of Solar-Terrestrial Physics, Siberian Branch, Russian Academy of Sciences, in summer 2023 are presented. It is confirmed that the cause of the prevailing direction of local winds appearing in SSO is the temperature mountain-valley gradient between the Sayan Mountains north of the SSO observatory and the valley to the south. A smaller level of the mean intensity of atmospheric turbulence in the SSO compared to the turbulence over a flat terrain in middle latitudes is confirmed. The presence of coherent turbulence in the SSO area is shown, at which the quality of images obtained by optical instruments is improved. New data are obtained for the turbulent scales of temperature and wind speed used in the Monin–Obukhov similarity theory depending on the atmospheric stratification. The results will be useful for specialists in astroclimate and theory of atmospheric turbulence.