ANTARCTIC ATMOSPHERIC CIRCULATION 
m, predominantly under the influence of the polar 
anticyclone; 3,000 m, the zone of transition between the 
low-level polar anticyclone and upper-level cyclone; 
and 5,000 m, definitely under the influence of the polar 
cyclone. The winds show a steady increase in velocity 
with heights to a marked maximum at the tropopause, 
25,000 to 30,000 ft, [and also] a slow increase in average 
velocity as fall approached, coinciding with an increase 
in the intensity and rate of movement of low-pressure 
areas.” 
The Interior. Only four areas of Antarctica more than 
100 miles from the coast have been explored on the 
surface: two converging routes to the South Pole, two 
routes from opposite directions to the south magnetic 
pole, the plateau due west of McMurdo Sound, and 
the center of Ellsworth Highland midway from the 
Palmer Peninsula to the Ross Sea. In all four areas, 
midsummer weather is variable, with clear days and 
cloudy, strong winds and light, snowfall and ablation. 
Prevailing winds observed by parties in these four 
areas are shown in Table II, adapted from Taylor 
[114], who considered both winds and sastrug?, the 
ridges or dunes of snow which indicate wind direction. 
Since convergence of the meridians makes it difficult 
to compare directions in different longitudes, directions 
are indicated by the parallel direction at the South Pole, 
measured in degrees eastward from Greenwich. 
Tasie JJ. Prevattinc WInDs OF INTERIOR 
ANTARCTICA IN SUMMER. 
(Referred to directions at the South Pole: 
90°E = 90°, 90°W = 270°) 
Party Year Area Wind 
Mawson and Bage 1912-13 | Adélie Land to the | 300° 
magnetic pole 
David 1908-09 | Victoria Land to the} 300° 
magnetic pole 
Scott 1903-04 | West of McMurdo | 360° 
Sound 
Shackleton 1908-09 | South of Beardmore | 320° 
Glacier 
Amundsen and Scott | 1911-12 | South Polar Plateau | 326° 
Ellsworth 1935 Hollick-Kenyon 20° 
Plateau 
These half-dozen average wind directions might in- 
dicate a general surface air motion in summer from the 
Weddell Sea toward the Ross Sea or Australia, opposite 
to the upper-air flow deduced by Barkow. They are 
compatible with a single surface anticyclone centered 
around 80°S, 70°E. By themselves, the prevailing winds 
around the magnetic pole and west of the Ross Sea are 
compatible with an anticyclonic cell centered around 
70°S, 155°H, roughly the position given by the High- 
jump aerologists and by Lamb for one cell of the polar 
anticyclone. The south polar plateau winds similarly 
would agree with another lobe, or perhaps the central 
cell, centered around 85°S, 70°H. 
Neither of these postulated cells, however, can be 
even semipermanent. “The wind,’’ David [118] reported, 
“had helped us by blowing from the southeast, just 
before we reached the Magnetic Pole, and now it was 
blowing in the opposite direction, helping us home.” 
921 
On 22 January 1909, “‘a clear day with bright sunshine, 
the wind started soon after 5 A.M., constantly freshen- 
ing, as it usually did in this part of the plateau, till 
about 3 P.M., then it gradually died down by about 10 
P.M.” 
On the south polar plateau, wind and weather in 
December 1911 and January 1912 were similarly vari- 
able. There, Simpson’s painstaking analysis [112] showed, 
63 per cent of all the winds recorded by Amundsen and 
Scott, representing 75 per cent of the total movement, 
were from 320°, 340°, or 360°, with resultant 326° at 
8.5 mph. But there were calms, winds from other di- 
rections, wide variation in the strength of the prevailing 
winds, and fresh snow as well as blowing snow. 
Most surprising, and least compatible with a theory 
of anticyclone cells, are the winds observed by Ells- 
worth [120] at three camps (at 80°S between 104° and 
115°W) made to wait out blizzards whose “hard, fine- 
grained” snow “is dry, fine as flour, sifts into every- 
thing, and packs hard as rock.” The first landing was 
made when clouds appeared and visibility grew poor; 
after nineteen hours there, ‘‘the weather was fine, 
though the horizon ahead looked thick” and after 30 
minutes’ flying, weather forced a second landing. 
“Three days of varying thick and clear weather” 
ensued; after a 50-minute flight “the weather became 
so thick we could scarcely see to land” and a three-day 
blizzard followed, with east to southeast winds esti- 
mated at 45 mph. On the fourth day, ‘December 1, 
the storm moderated . . . with intervals of sunshine .. .. 
Buffeting wind, snow, and thick weather . . . bitterly 
cold”’ came on the fifth day, and heavy snow that night. 
On the sixth day, another “heavy storm broke from 
the southeast—thick snow and a high wind.”’, 
Finally on the seventh day, although ‘‘the weather 
was anything but promising, with thick horizons all 
around and a sullen sky overhead,” the flight was re- 
sumed, and an hour later they encountered “blue sky 
with a clean horizon all around” at the western edge of 
the plateau. “Evidently the storm area had been hang- 
ing stationary near the western edge” of the plateau. 
Both in the air (usually at 10,000 ft, some 4000 ft above 
the surface) and on the ground, during these eleven days 
of the only visit to date to this area, all winds were from 
east or southeast, except for two brief periods of north 
wind; “it never did blow from the west”; south winds 
were first encountered as the Ross Shelf Ice was reached. 
These weather conditions are similar to those along 
the coasts and seem out of keeping for the center of an 
“unbroken desert of snow” 6000 ft above sea level. 
Ellsworth thought the then unknown coastline was 
“450 miles to the north,’ but explorations in 1940 
[121] and 1947 [116] revealed a large bay or a large 
island-choked, ice-filled gulf at the head of Amundsen 
(formerly Roosevelt) Sea. This indentation, as yet un- 
named and unmapped in detail from the available 
aerial photographs, appears to reach to about 77°S 
at 105°W, or only some 200 miles from Ellsworth’s first 
camp, explaining “the water sky observed by Hollick- 
Kenyon on Nov. 238 in the conjectured position of 76°S 
and 100°W.” 
