Abstract
Polar mesosphere summer echoes (PMSEs) have been well studied using vertical incidence VHF radars at northern high-latitudes. In this paper, two PMSE events detected with the oblique incidence SuperDARN HF radars at Hankasalmi, Finland (62.3°N) and Syowa Station, Antarctica (69.0°S), are analyzed, together with simultaneous VHF and medium-frequency (MF) radar data. Altitude resolutions of the HF radars in the mesosphere and the lower thermosphere are too poor to know exact PMSE altitudes. However, a comparison of Doppler velocity from the HF radar and neutral wind velocity from the MF radar shows that PMSEs at the HF band appeared at altitudes within 80-90 km, which are consistent with those from previous vertical incidence HF-VHF radar results. The HF-VHF PMSE occurrences exhibit a semidiurnal behavior, as observed by other researchers. It is found that in one event, PMSEs occurred when westward semidiurnal winds with large amplitude at 85-88 km altitudes attained a maximum. When the HF-VHF PMSEs were observed at distances beyond 180 km from MF radar sites, the MF radars detected no appreciable signatures of echo enhancement.
Original language | English |
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Pages (from-to) | 4049-4059 |
Number of pages | 11 |
Journal | Annales Geophysicae |
Volume | 22 |
Issue number | 12 |
DOIs | |
Publication status | Published - 2004 |
Externally published | Yes |
Keywords
- Meteorology and atmospheric dynamics (middle atmosphere dynamics; thermospheric dynamics; waves and tides)
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Geology
- Atmospheric Science
- Earth and Planetary Sciences (miscellaneous)
- Space and Planetary Science