Mie scattering refers primarily to the elastic scattering of light from atomic and molecular particles whose diameter is similar or larger than the wavelength of the incident light. We can say that, when the particle has a diameter greater than about a tenth of the wavelength, we are in the field of Mie scattering.
This scattering produces a pattern like an antenna lobe, with a forward lobe sharper and more intense than the back one, the larger the particle size the greater the intensity and sharpness of the anterior lobe. Unlike Rayleigh scattering, Mie scattering is not strongly wavelength dependent. In this case the predominant component for the quantification of scattering (in addition to the particle dimension) is the direction of the incident solar radiation.
More specifically, the amount of scattering in the backward direction depends upon a wave relation tending to decrease in accordance with the growth of the particle size until it reaches a certain value for which the back scattering becomes a constant quantity. This condition is reached when the diameter of the particle is approximately equal to the wavelength of the incident radiation.
In the atmosphere the Mie scattering is commonly caused by particles (aerosols) floating in the atmosphere (due to Dust, smoke, fog, rain drop).
In nature it is possible to see the effects of Mie scattering, for example, in the evenings when there is a lot of fog and the dazzling headlights of our car do not allow us to see the road ahead.
The Mie theory provides the solution for the amount of scattering in case of a spherical medium due to an incident wave.