Influence of Internal Gravity Waves in the Atmospheric Boundary Layer on Turbulence Characteristics Measured by the Eddy Covariance Technique

This paper presents the results of an analysis of the influence of submesoscale internal gravity waves (IGWs), registered with the help of a sodar in the atmospheric boundary layer, on turbulence characteristics measured in the surface layer. Data obtained in rural areas in the Moscow region are used. Two types of IGWs are identified visually on sodar echograms: internal gravity-shear waves (IGSW) of the Kelvin–Helmholtz billow type and buoyancy waves (BWs). For 28 episodes of IGSWs and 10 episodes of BWs, turbulent kinetic energy, as well as heat and momentum fluxes, is calculated based on the data of eddy covariance measurements carried out with an ultrasonic thermometer–anemometer located on a mast 56 m above ground level. Variations of these characteristics accompanying the passage of wave trains are investigated, quantitative estimates are made, and the degree of influence of IGSWs and BWs on the turbulence is compared.