7 Conclusions

Our key results can be summarised as follow:

• The winter turbulence above the South Pole is characterised by a single, low altitude component. Autumn and Spring vary between a concentrated and an extended profile of turbulence.
• The turbulence as a function of height follows closely the horizontal wind profile while always sitting below it.
• The turbulence peaks in the zone of vertical wind inversion.
• The average seeing, while poor at ground level ( $1.73^{\prime\prime}$), improves very quickly within the first 300 m of the atmosphere ( $0.61^{\prime\prime}$).
• The extent of the boundary layer might be too high to place a telescope on a high tower, but is concentrated enough that the isoplanatic angle and coherence time are the best ever observed. Through the use of adaptive optics, the South Pole could outperform all other sites so far studied.

Acknowledgements

This research was supported by grants from the Australian Research Council (ARC) and the University of New South Wales (UNSW). Logistic and infrastructure support were supplied by CARA and the NSF. We thank Daniel Marlay and Jessica Dempsey for help in "winterising" the SODAR and installing it at the South Pole. We also would like to thank Marc Sarazin for his advice on the use of a SODAR to investigate the seeing as well as J. Beckers for his valuable comments.