Aspect sensitivity of polar mesosphere summer echoes observed with the EISCAT VHF radar

Abstract

The European Incoherent Scatter Scientific Association (EISCAT) Very High Frequency (224 MHz) Radar has been used to investigate the aspect sensitivity of polar mesosphere summer echoes (PMSE) in the period 13–15 July 2010. The aspect sensitivity of PMSE using this radar and at such a high frequency has not been previously reported. Data concerning the aspect sensitivity of PMSE were collected by traversing the antenna beam from the zenith direction, and comparing the received power. Surprisingly, as the intensity received by the oblique beam was often larger than that of the vertical beam, suggesting the presence of tilted dusty plasma layers as a potential cause, a theoretical model was developed to confirm the existence of these layers and their formation process. The experimental results and theoretical model presented help elucidate the structural properties of the possible generation mechanism of strong radar echoes in the polar summer mesosphere region. Citation: Li H, Wu J, Tian R H, et al. Aspect sensitivity of polar mesosphere summer echoes observed with the EISCAT VHF radar. Adv Polar Sci, 2018, 29(1): 34-39, doi: 10.13679/j.advps.2018.1.00034