Page:Physical Geography of the Sea and its Meteorology.djvu/481

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THE ANTARCTIC REGIONS AND THEIR CLIMATOLOGY.
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in the ice there. The annals of Greenwich at St. Petersburg give us the mean height of the barometer in lat. 51° 29' N., according to three years' observations, and in lat. 59° 51' N., according to ten years of observation. Such are the sources of the table.

Mean Height of the Barometer

Latitude. Barometer. No. of
Observations.
Latitude. Barometer. No. of
Observations.
0° to 5° N. 29.915 5114 0° to 5°S. 29.940 3692
5 ,, 10 29.922 5343 5 ,, 10 29.981 3924
10 ,,15 29.9(54 4496 10 ,, 15 30.028 4156
15 ,,20 30.018 3592 15 ,, 20 30.060 4248
20 ,,25 30.081 3816 20 ,, 25 30.102 4536
25 ,,30 30.149 4392 25 ,, 30 30.095 4780
30 ,, 35 30.210 4989 30 ,, 36[1] 30.052 6970
35 ,, 40 30.124 5103 40 ,, 43 29.88 1703
40 ,, 45 30.077 5899 43 ,, 45 29.78 1130
45 ,, 50[1] 30.060 8282 45 ,, 48 29.63 1174
51° 29' 29.814[2]> Greenwich 48 ,,50 29.62 672
59° 51' 29.88 St. Petersburg 50 ,, 53 29.48 665
      53 ,,55 29.36 475
78° 37' 29.759 Dr. Kane 56½ 29.29 1126

856. The low austral barometer.—Captain Wilkes, U. S. N., and Clarke Ross, R.N., both, during their expeditions to the South Seas in 1839-41, had occasion to remark upon the apparent deficiency of atmosphere over the extra-tropical regions of the southern hemisphere; and the low barometer off Cape Horn had attracted the attention of navigators at an early day. I observed it in 1831 when doubling the Cape as master of the U.S.S. "Falmouth," and wrote a paper on it, which was published in the American Journal of Science in 1833-4. The more abundant materials which the abstract logs since placed within my reach have enabled me to go more fully into this subject than it was possible to do while I was cruising in the Pacific more than a quarter of a century ago. To ascertain whether these "barometric anomalies," as they are called, are peculiar to the regions about Cape Horn, or whether they are common to high southern latitudes in all longitudes, the observations about Cape Horn were arranged in one group; those between 20° W. and 140° E.

  1. 1.0 1.1 Maandelijksclie Zeibaanwijzingen van Java naar Het Kanaal. Als Litkomsten Wetenschap en Ervaring Aangaande Winden on Zeestroomingen in Sommige Gedeetten Van Den Oceaan Uitgegenen Door Meet Koninklijk Nederlandsch Meteorologische Institut. Utrecht, 1859.
  2. The mean height of the barometer for England generally is 29.94°.—Admiral Fitzroy