The paper analyzes the phenomenon of turbulent thermal diffusion in the Earthatmosphere, its relation to the turbulent diffusion and its potential impact onaerosol distribution. This phenomenon was predicted theoretically more than 10years ago and detected recently in the laboratory experiments. This effectcauses a non-diffusive flux of aerosols in the direction of the heat flux andresults in formation of long-living aerosol layers in the vicinity oftemperature inversions. We demonstrated that the theory of turbulent thermaldiffusion explains the GOMOS aerosol observations near the tropopause (i.e.,the observed shape of aerosol vertical profiles with elevated concentrationslocated almost symmetrically with respect to temperature profile). Incombination with the derived expression for the dependence of the turbulentthermal diffusion ratio on the turbulent diffusion, these measurements yield anindependent method for determining the coefficient of turbulent diffusion atthe tropopause. We evaluated the impact of turbulent thermal diffusion to thelower-troposphere vertical profiles of aerosol concentration by means ofnumerical dispersion modelling, and found a regular upward forcing of aerosolswith coarse particles affected stronger than fine aerosols.
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