Extracting Zonal Propagation Information of Atmospheric Tides from Single Site Specular Meteor Radar Observations

Monostatic specular meteor radars (SMRs) have long been used to investigate atmospheric tides and seasonal waves in the mesosphere/lower thermosphere (MLT) [Forbes et al.,1999, Holdsworth et al., 2004, McKinley, 1961]. Winds derived from SMRs are typically averaged in time over 1 hour, and averaged in altitude over 2 km or larger slices [Marino et al., 2022, Hocking et al., 2001]. While standard SMR processing techniques are useful for determining the temporal periodicity and magnitude of atmospheric waves [Forbes, 1995, Wang et al., 2021], the reduction of observations across ∼200,000 km2 to a single wind vector fails to extract all available information — this simplification obfuscates waves’ propagation information [Marino et al., 2022].

One approach to this problem is to divide the spatial extent of observations into multiple zones, making the progression of waves across the instrument’s field-of-view discernible. Given atmospheric tides propagate zonally, this work organizes observations into east-west bins perpendicular to the direction of propagation [Forbes, 1995, Forbes et al., 1999]. Stratifying observations into a small number (2-5) of east-west bins allows the propagation of wavefronts across the radar field of view to be seen, revealing the waves’ direction of travel and spatial periodicity. The first step in validating this technique is sampling a simulated wind field constructed of a mean wind and tidal perturbations, which are the dominant periodicity, and sampled using real meteor distributions. Using meteor observations from the McMurdo monostatic SMR the seasonal variation of diurnal and semi-diurnal MLT tides is investigated.