Small scale structures of a mesospheric dusty plasma

A dusty plasma model is presented to study the small scale structures of plasma densities in mesopause region associated with polar mesosphere summer echoes (PMSE). The heavy dust grains (ice particles) are treated as a flowing background of negative charge. Numerical results show that the electron and ion densities drop rapidly while the electric field increases dramatically within a short distance of several meters. The scalelengths of the electron density are comparable to the typical wavelength of the PMSE radars, which may be responsible for strong radar backscatter. Furthermore, the increase of the ice particle concentration results in the reduction of the density gradient and electric field.