First VHF radar measurements of mesopause summer echoes at mid-latitudes

Abstract

Observations of the summer mesosphere using the stationary SOUSY VHF (53.5 MHz) radar located in the Harz mountains of Germany (52°N, 10°E) indicate the presence of very strong radar returns from heights near 85–86 km on some occasions. These echoes occur in the form of a layer with a full‐power half‐width of less than about 1 km, and exhibit an aspect sensitivity of about 1 dB deg−1. These features are very similar to those of the so‐called Polar Mesopause Summer Echo (PMSE) known to occur at high latitudes and suggest a common production mechanism.