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A case study of a sporadic sodium layer observed by the ALOMAR Weber Na LIDAR

 
: Nesse, H.; Heinrich, D.; Williams, B.; Hoppe, U.-P.; Stadsnes, J.; Rietveld, M.; Singer, W.; Blum, U.; Sandanger, M.I.; Trondsen, E.

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Annales Geophysicae 26 (2008), Nr.5, S.1071-1081
ISSN: 0939-4176
ISSN: 0980-8752
ISSN: 0992-7689
ISSN: 0980-8760
ISSN: 1432-0576
Englisch
Zeitschriftenaufsatz, Elektronische Publikation
Fraunhofer INT ()
atmospheric composition and structure; ion chemistry of the atmosphere; thermosphere-composition and chemistry; ionosphere; ionosphere-atmosphere interactions; ionospheric irregularity

Abstract
Several possible mechanisms for the production of sporadic sodium layers have been discussed in the literature, but none of them seem to explain all the accumulated observations. The hypotheses range from direct meteoric input, to energetic electron bombardment on meteoric smoke particles, to ion neutralization, to temperature dependent chemistry. The varied instrumentation located on Andoya and near Tromso in Norway gives us an opportunity to test the different theories applied to high latitude sporadic sodium layers. We use the ALOMAR Weber sodium lidar to monitor the appearance and characteristics of a sporadic sodium layer that was observed on 5 November 2005. We also monitor the temperature to test the hypotheses regarding a temperature dependent mechanism. The EISCAT Tromso Dynasonde, the ALOMAR/UiO All-sky camera and the SKiYMET meteor radar on Andoya are used to test the suggested relationships of sporadic sodium layers and sporadic E-layers, electron precipitation, and meteor deposition during this event. We find that more than one candidate is eligible to explain our observation of the sporadic sodium layer.

: http://publica.fraunhofer.de/dokumente/N-75311.html