Characteristics of atmospheric optical turbulence and wind profile at the Muztagh-ata site on the Pamir Plateau

ABSTRACT In this paper, the wind field characteristics and optical turbulence profiles at the Muztagh-ata site are characterized using a Coherent Doppler Wind Lidar (CDWL) and a seeing monitor. A distinct stratified wind structure with significant seasonal and diurnal variations is observed at the site; wind speeds are higher in winter and lower in summer, with a stable prevailing wind direction from the south-west across all altitude layers. At the North 1 point, statistical analysis from 2025 November 18 to 2026 January 11, shows a median nighttime seeing of 0.80 arcsec at 6 m, with an interquartile range of 0.62–1.07 arcsec, indicating favourable optical observing conditions. By synthesizing multi-instrument data sets, this study quantitatively evaluates the contribution of different atmospheric layers to the total integrated seeing. The results show that the boundary layer (6–1000 m) contributes a median of 59 per cent to the total atmospheric seeing. Notably, the near-surface layer below 200 m accounts for over 63 per cent of the turbulent energy within the 6–1000 m range, identifying it as the primary physical layer limiting observational quality. The findings provide important scientific basis for the site selection of large-aperture telescopes and the development of AO systems at the Muztagh-ata site.