Measurement of Optical Seeing on the High Antarctic Plateau

• Main Authors: Marks Vernin Azouit, R. D. Marks, J. Vernin, M. Azouit, J. F. Manigault, C. Clevelin
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1997
• Subjects: Antarctic; Fuchs; South Pole; Antarc*; South pole
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.27.3724; http://www.phys.unsw.edu.au/~mgb/Antbib/aa_balloon.ps.gz

. Results from the 1995 season of site-testing experiments at the South Pole are presented, in which the seeing was measured using balloon-borne microthermal probes. Our analysis shows a marked division of the atmosphere into two characteristic regions: (i) a highly turbulent boundary layer (0--220 m) associated with a strong temperature inversion and wind shear, and (ii) a very stable free atmosphere. The mean seeing, averaged over 15 balloon flights, was measured to be 1:86 00 , of which the free atmosphere component was only 0:37 00 . The seeing from 200 m upward is superior to the leading midlatitude sites (e.g. Fuchs 1995, Roddier et al. 1990) by almost a factor of two. The results are in good agreement with optical seeing data obtained by a differential image motion monitor on three of the five occasions when the two measurements were performed simultaneously. The boundary layer winds are of katabatic origin, and so we may consider the possibility of exceptional seeing condit.