On the Correlation between the sodium in the MLT and meteor radiant distribution

Abstract

The sodium layer in the mesosphere and lower thermosphere (MLT) region is originated from meteoroid mass deposits produced by its ablation. Understanding the correlation between the meteoroid material input and the concentration of the sodium layer is essential for many investigations that use sodium as a tracer to study the dynamics in the MLT. A new numerical sodium chemistry model has been developed to study such correlation, and the results are cross-compared to the meteoroid material input inferred from the recently revealed sporadic meteor radiant distribution derived from the data gathered by the Arecibo Observatory. The sodium chemistry model is computationally efficient, runs in high-time resolution, and the sodium-bearing species are equally treated in the continuity equation devoid of making any steady-state approximation. This work will also present the seasonal and latitudinal distribution of meteoroid injection rates derived from the aforementioned sporadic meteor radiant distribution.Our simulation results agreed with the general feature of the measurements obtained from the Colorado State University Lidar (CSU) and the Andes Lidar Observatory (ALO) but with variations three times smaller.