Figure A-3. — Icebreakers at Neny Island, Antarctica. 



smoke from the volcanic Mount Erebus (13,000 feet). In the 

 McMurdo Sound region the clouds between 10,000 and 13,000 

 feet and the smoke from Mount Erebus indicated prevailing winds 

 between west and north, the opposite of the surface direction on 

 the Ross Barrier, and associated presumably with the cyclonic 

 circulation of the middle atmosphere. (See table II and III.) 



VISIBILITY 



Due to the absence of dust, solid particles, and the low moisture 

 content of winds blowing off the antarctic continent, visibility is 

 often unusually great and mirage effects are often experienced. 



210 



I 



