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Title: Mesospheric anomalous diffusion during noctilucent cloud scenarios
Abstract. The Andenes specular meteor radar shows meteor trail diffusion rates increasing on average byabout 10 % at times and locations where a lidar observes noctilucentclouds (NLCs). This high-latitude effect has been attributed to the presenceof charged NLC after exploring possible contributions from thermal tides. Tomake this claim, the current study evaluates data from three stations athigh, middle, and low latitudes for the years 2012 to 2016 to show that NLCinfluence on the meteor trail diffusion is independent of thermal tides. Theobservations also show that the meteor trail diffusion enhancement during NLCcover exists only at high latitudes and near the peaks of NLC layers. Thispaper discusses a number of possible explanations for changes in the regionswith NLCs and leans towards the hypothesis that the relative abundance ofbackground electron density plays the leading role. A more accurate model ofthe meteor trail diffusion around NLC particles would help researchersdetermine mesospheric temperature and neutral density profiles from meteorradars at high latitudes.  more » « less
Award ID(s):
1755350
PAR ID:
10176983
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Atmospheric Chemistry and Physics
Volume:
19
Issue:
7
ISSN:
1680-7324
Page Range / eLocation ID:
5259 to 5267
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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