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without direct influence during that period, Imt in similar latitudes in the Arctic zone it is usual to find 

 the lowest temperatures most decidedly at the end of the long winter. 



The observations of the " Discovery " show a fall of temperature to - 12 in April, which should hardly 

 be called a winter month, a mean through the winter of about - 15. September, the month about 

 equally distant on the other side from midwinter, has 15 - 4. If these results had been obtained from 

 one year's observations only, it would be reasonable to think that the autumn had been unusually severe 

 and the spring unusually mild ; but the same peculiarity is observed in both years, and it is further borne 

 out by the mildness of June when compared with July. 



The low mean temperature of the summer is also strange, and very difficult to explain. In lower 

 southern latitudes, in the neighbourhood of Gape Horn, for example, the summer is very cold compared 

 with that of places with the same northern latitude, but in this case the explanation is simple. The 

 annual change of temperature over the great oceans is small on account of the large thermal capacity of 

 the water and the constant mixing together of the surface layers, and a small annual change produces a 

 cool summer and a warm winter, as is notably the case in England. 



The insolation in the Antarctic in summer is greater than the insolation on any other part of the earth 

 at any other time, this being the date at which the sun is nearest to the earth, and if temperature 

 depended only on solar radiation we should have the highest terrestrial temperatures occurring in 

 December in the neighbourhood of the South Pole. A largo mass of ice prevents the temperature from 

 rising much above the freezing point, because the air, being nearly pervious to radiation, takes its 

 temperature chiefly from the surface with which it is in contact, and if that surface be ice or snow it 

 cannot be above 32 F. But ice, except in its power of evaporation, is in no way more efficacious than any 

 other rock in checking a rise of temperature up to its own melting point. Why then does not the mean 

 summer temperature at least reach the freezing point, as indeed it does in the North Polar regions, where 

 the insolation is less intense ? During the two years that the " Discovery " was in the Antarctic circle 

 there were only five days with a mean temperature above the freezing point ; the mean temperature of the 

 warmest month was 26'2, and the mean temperature of what in other localities would be called the six 

 summer months (three each year), was 20 - 7. In further proof of the lowness of the summer temperature, 

 the fact that no rain ever fell may be cited, the precipitation always taking the form of snow. 



These low summer temperatures in the Antarctic region are fully supported by the results of the 

 Swedish expedition under Dr. OTTO NORDENSKJOLD, and that of the "Southern Cross " under BORCHGREVINK. 



The following figures are taken from the ' Meteorologische Zeitschrift ' for July, 1905, p. 320 : 



The Arctic temperatures experienced by the " Fram " in a far higher latitude are shown below : 



'Norwegian North Polar Expedition, 1893-96,' vol. vi. 



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