HR: 08:20h
AN: SA41A-02 INVITED     [PDF]
TI: Meteors and their impact on the atmosphere
AU: * Plane, J M
EM: j.plane@uea.ac.uk
AF: University of East Anglia, School of Environmental Sciences, Norwich, NR4 7TJ United Kingdom
AB: This paper will begin with an overview of the mesosphere/lower thermosphere (MLT), and the historical role that meteors and the metal layers produced by meteoric ablation have played in understanding the region. The MLT is characterised by enormous seasonal variations in temperature, very low pressures, and is subject to solar radiation extending into the extreme ultra-violet. In addition, more than 50 tonnes of interplanetary dust enters the atmosphere each day, mostly ablating in the MLT region. All of these features contribute to a very unusual chemistry that is quite distinct from the lower atmosphere. Phenomena that will be discussed include: aspects of meteoric ablation; the global layers of metal atoms such as Na and Fe; the Na airglow; sporadic layers of metal ions and neutral atoms; and the role of meteor smoke. I will emphasise the contribution that laboratory studies can make to advancing MLT science, because the region is so difficult to explore directly.
DE: 0310 Airglow and aurora
DE: 0317 Chemical kinetic and photochemical properties
DE: 0335 Ion chemistry of the atmosphere (2419, 2427)
DE: 0340 Middle atmosphere--composition and chemistry
DE: 0355 Thermosphere--composition and chemistry
SC: SPA - Aeronomy [SA]
MN: 2003 Fall Meeting