GEOLOGICAL OBSERVATIONS 



and in this way arises the so-called floating inland-ice, which, in the Northern 

 Hemisphere, is only known in the northern extremity of Greenland. 



The surface of the ocean-ice in front of the glacier is in the course of the 

 summer subjected to exactly the same degree of melting as the floating inland- 

 ice, which, because of this very melting, has become jnireaeingli.- thinner 

 towards the point. The result is that the outermost paflG»£_ilie. glacier-ice and 

 the ocean-ice assume an extraordinary similarity ; they merge into each other, 

 and in certain fjords — for instance, Victoria Fjord — there is on the whole no 

 definite line of demarcation between the ocean-ice and the glacier-ice as they 

 merge evenly into each other. 



To understand this question one must examine the conditions of summer 

 here in the most northerly regions of the world, bounded to the south by the 

 entire inland-ice and to the north by the permanent ice cover of the Polar 

 Sea. In the following we will attempt to describe the climate of North Green- 

 land and its relation to the inland-ice. 



The whole of South Greenland receives sunlight by noontime of the 

 shortest day of the year. The rays of the sun do not, however, reach to 

 Holstenborg on that day ; only on the following day does it show above the 

 horizon, and for every succeeding day it sends its rays further northward, 

 putting an end to the dark period. In the course of January the sun reaches 

 the whole of Danish Greenland, with the exception of Upernivik; in the 

 course of February it reaches the Cape York district, and not until March 

 does it shine on the mountains of Peary Land, after a dark period of 

 nearly four months. During the latter half of the dark period, in January 

 and February, and also in March, the temperature has been down to about 

 minus 40° C. the whole time. In the beginning of April the midnight sun 

 commences, but the orbit of the sun is so flat in these latitudes during this 

 month that its power is only slight. The air is warmed up to about minus 

 23° C, but by the 1st of May the land still lies in its winter state. Tn the 

 middle of May the first sign of spring is apparent, as snow-flakes lying on 

 stones which turn towards the sun evaporate, and occasionally even a drop of 

 water may be observed. A puff of wind, and it is forthwith once more 

 turned into ice ; but a moment after it reappears, and the patch of snow on 

 the stone has become slightly smaller. In the beginning this melting and 

 evaporation take place to a very small extent, but by the middle of May the 

 development becomes more rapid. By noon the sun shines brilliantly on the 

 mountains, which are still entirely covered with snow ; during the afternoon 

 a fog is formed round the highest summits, spreading more and more; in the 

 evening it has become thick, and a fine layer of snow crystals falls on ice and 

 land. This is part of the snow which evaporated at noon. The next day the 

 sun again gains in strength ; on the mountain-side, where its rays fall almost 

 vertically, it makes light work of the loose snow crystals which have fallen 

 during the night ; they evaporate rapidly, and the evaporation of the firmer 

 snow masses then continues. 



The sun, however, has hardly any power on the horizontal ocean-ice ; its 

 position is so low that the rays fall obliquely, wherefore the snow crystals 

 which fell during the night remain lying and do not evaporate. So in the 

 month of May one may see snow-bare patches on land becoming increasingly 

 larger, at the same time as sledge tracks on the ocean-ice slowly but surely 

 are snowed under. In this way quite considerable quantities of snow are 

 transferred from the land to the ocean-ice. Naturally, during this period fogs 



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