The role of extraterrestrial particles in the formation of the ozone hole. Part I: The concentration of extraterrestrial particles at ozone hole formation

• Main Authors: Rosinski, J., Kerrigan, T.C.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Societa italiana di fisica 2001
• Subjects: 551 Geologia; Idrologia; Meteorologia; South Pole; Antarc*; Antarctica; South pole
• Online Access: http://eprints.bice.rm.cnr.it/14731/; http://eprints.bice.rm.cnr.it/14731/1/ncc8780.pdf; https://www.sif.it/riviste/sif/ncc/econtents/2001/024/06/article/4

The object of Part I of this paper is to estimate the concentration of extraterrestrial particles in the ozone layer over South Pole, Antarctica, during ozone hole formation. This estimate is based on an analysis of microscopic magnetic spherules collected in an extended program of atmospheric sampling. Spherules are shown to be of extraterrestrial origin and serve as markers for the larger class of less distinguished extraterrestrial particles. These particles settle to ground level as aggregates formed in a stratospheric ice crystal coalescence process. Specific spherule arrivals at ground level are strongly associated with apparent ozone depletion episodes during formation of the ozone hole. The origin of these spherules is a major stream of extraterrestrial particles independent of known meteor showers. The variability in its intensity from year to year corresponds to the variability in ozone depletion in the ozone hole itself. A quantitative theory based on these spherule arrivals and this coalescence process implies that the concentration of extraterrestrial particles at ozone hole formation lies between500 and 2000 / m3. A mechanism is proposed in Part II of this paper by which particle concentrations in this range are sufficient to produce the ozone hole.