关键词: 巴丹吉林沙漠, 近地大气边界层, 气象要素, 廓线结构

Abstract:

Using near-surface atmospheric boundary layer gradient observations from three stations during 2024-2025， this study systematically investigates the seasonal characteristics of near-surface wind speed， air temperature， and specific humidity profiles under typical clear-sky conditions in the desert interior and along the southeastern margin of the Badain Jaran Desert. The principal findings are summarized as follows. （1） Across different underlying surfaces， near-surface wind speeds are consistently higher during the daytime and lower at night， with the nocturnal boundary layer characterized by stable stratification and intensified wind shear. Among the three sites， the wind speed profile at the Sand Dune Station exhibits the strongest agreement with a power-law formulation， whereas those at the Lakeside Station and the Yabulai Mountain Station are more accurately described by exponential functions. （2） Near-surface air temperature decreases in the order of Lakeside Station， Sand Dune Station， and Yabulai Mountain Station. Temperature profiles display pronounced diurnal variability， with the nocturnal near-surface atmosphere tending toward near-isothermal conditions or developing temperature inversions. The most intense inversions occur in winter， and the inversion layer heights at the Lakeside and Yabulai Mountain Stations are greater than those at the Sand Dune Station. （3） Near-surface specific humidity is highest at the Lakeside Station and lowest at the Sand Dune Station， with a clear seasonal ranking of summer greater than autumn greater than spring greater than winter. At the Sand Dune Station， humidity inversion occurs above 4 m throughout all seasons. At the Lakeside Station， humidity inversion is observed above 2 m during nighttime in spring and winter and above 8 m in summer and autumn. At the Yabulai Mountain Station， humidity inversion frequently appears within the 4-8 m layer， and it is observed throughout the entire day in winter. The research results provide fundamental data to support leading scientific conservation efforts for the Badain Jaran Desert World Heritage Site and to improve boundary layer parameterizations in regional numerical models， thereby deepening the understanding of the formation mechanisms of mega-dunes.

Key words: Badain Jaran Desert, near-surface atmospheric boundary layer, meteorological elements, profile structure