Wave signatures in the polar mesopause region

• Main Authors: Kristoffersen, S., Fraser, D., Ward, W., Preusse, P., Strube, C.
• Format: Conference Object
• Language: English
• Published: 2023
• Subjects: Canada; Ellesmere Island; Eureka; Nunavut
• Online Access: https://gfzpublic.gfz-potsdam.de/pubman/item/item_5021072

The Polar Environment Atmospheric Research Laboratory (PEARL), established in 2005 at Eureka, Nunavut, Canada on Ellesmere Island (80N 85W), provides observations of the polar atmosphere from the ground to the lower thermosphere. Observations of wave signatures using an all-sky imager and the E-Region Wind Interferometer (ERWIN) with periods from 10’s of minutes to ~14 hours are examined. Horizontal winds are intermittent and the amplitude spectra peak in the 6 – 12 hour period region. This peak is not seen in the vertical wind and airglow brightness spectra. It appears that waves in this period range are not tidal in nature but are inertial gravity waves. A few wave events with periods of ~3 hours have been analysed using a gravity wave ray tracing program (GROGRAT) and found to be related to strong tropospheric storms. Short period gravity waves were also identified in the imager observation and explored using GROTGRAT. Their observed characteristics, suggest they are secondary waves associated with orographic gravity wave dissipation. The variety of characteristics and sources of these waves point to the complex nature of waves propagating into the polar ionosphere.