Capture of Meteoric Material by Mesospheric Ice Particles

In the Earth's polar summer mesosphere, the co-existence of ice and meteoric material gives rise to complex particle processes. A charge-dependent coagulation model has been developed to describe the interaction between these mesospheric players. Substantial capture rates are found for both metal atoms and smoke particles of meteoric origin. This results in a local atmospheric depletion of meteoric material and a typical mass mixing ratios of 0.1% to 1% meteoric material in the ice. This affects both charging properties and optical properties of noctilucent clouds and related particle phenomena. Open questions concern the "processing" of the meteoric material in the ice and the fate of accumulated metal species and charges upon ice sublimation at the end of the life cycle of mesospheric clouds.