Sarkar and Ulich, EGU, 2023

Abstract

Sodankylä's high latitude location serves an ideal ground for testing more comprehensive physics theory related to radio meteor data. The atmospheric scale height shows significant variation at this latitude. Also, the observational geometry towards the plane of ecliptic plane changes drastically with seasons. On theory, the reflected radio signal from the ablating meteor train can be used to continuously monitor atmospheric temperature at the 90 km altitudes. In practice, complication arises due to the selection effects in the system as well as the persistent effect of natural variability (size, mass, velocity, entry angle) in meteoroids property. The long-standing hypothesis that needs to be debated: Is the assumed equality between atmospheric scale height (H_KT) and the effective diffusion scale height (H_D) of meteor trails valid for these data? In this study, we argue that such an hypotheis can not be experimentally validated, and hence the need for subsequent calibration. Furthermore, long-term trend analysis showed that the discrepancy between H_KT and H_D has non-linear seasonal trends. Alternatively, we demonstrate an alternative method of scale-height measurement based on meteor height distribution. The technical and theoretical limits of this methodology are discussed and validated using 10 years of observational data.