A case study of a sporadic sodium layer observed by the ALOMAR Weber Na lidar
Article, Other literature type
Rietveld, Michael T.
Sandanger, M. I.
- Publisher: European Geosciences Union (EGU)
(issn: 1432-0576, eissn: 1432-0576)
ionosphere-atmosphere interactions | ion chemistry of the atmosphere | VDP::Mathematics and natural science: 400::Physics: 430::Space and plasma physics: 437 | VDP::Matematikk og naturvitenskap: 400::Fysikk: 430::Rom- og plasmafysikk: 437 | ionospheric irregularities | atmospheric composition and structure | ionosphere | thermosphere-composition and chemistry | ionospheric irregularity
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 Andøya and near Tromsø 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 Tromsø Dynasonde,
the ALOMAR/UiO All-sky camera and the SKiYMET meteor radar on Andøya 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.