On Algebraic Perturbations in the Atmospheric Boundary Layer

Abstract

A simple model for the development of submesoscale perturbations in the atmospheric boundary layer (ABL) is proposed. The growth of perturbations is associated with the shear algebraic instability of the wind velocity profile in the ABL. Seeking optimum values of such perturbations (streaks) allows one to solve the problem of estimating their scales, which turn out to be about 100–200 m vertically and 300–600 m horizontally. Similar scales are also revealed for experimental data on the structure of the wind field in the lower part of the ABL; the data were obtained in 2017 and 2018 in summer at the Tsimlyansk Scientific Station of the Obukhov Institute of Atmospheric Physics during acoustic sounding of the atmosphere with a high-resolution three-component Doppler minisodar.