A quarter of a century of polar mesospheric summer echo observations over Andøya: climatology and trends
Leibniz Institute of Atmospheric Physics at the Rostock University, Schloss-Str. 6, 18225 Kühlungsborn, Germany
Franz-Josef Lübken
Leibniz Institute of Atmospheric Physics at the Rostock University, Schloss-Str. 6, 18225 Kühlungsborn, Germany
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Short summary
Using 30 years of radar observations at Andøya, this study presents the world’s longest record of a rare summer phenomenon high above the Arctic. The season lasts about 104 days and is gradually starting earlier and ending later. Even after accounting for solar and geomagnetic effects, a small but steady rise remains. The strongest signals occur about 84 km up and show no long-term change, offering new insight into ongoing shifts in the upper atmosphere.
Using 30 years of radar observations at Andøya, this study presents the world’s longest record...