Stratocumulus clouds cover a large fraction of the Earth’s surface and have a strong influence on the radiation budget of the Earth and hence climate. Microphysical and optical properties of stratocumulus clouds are described in relation to the entrainment and mixing between cloudy air and environment. The experimental data was carried out during ACE2 experiment and in the analysis two cloud samples were compared: of marine and anthropogenic origin. Special attention was paid to k factor, its variety, and to how cloud characteristics depend on that factor. Conducted analysis hasn’t shown any noticeable trend.