[en] A method to measure the content of aerosol in smoke plume, observed from the ground, using a multichannel radiometer has been proposed. The case in which the radiometer is looking vertically upwards and is travelling on the ground across the projection of the plume was carefully considered. The sky is assumed to be a uniformly emissive lightsource. The extinction coefficient is measured in each spectral channel. After some simplifying assumptions a system of equations is written. On its base the aerosol emission in the plume can be computed when the wind velocity on the plume level is known. The main problem is the determination of extinction coefficients σ (α, lambda) for different particle sizes α and channel wavelengths lambda. For this purpose a formula given by Zujew can be used but it is necessary to know - or to assume - some physical characters of the particles. Different versions of the method can be applied. Experiments are planned. (author)