fragmentation of the ice indicates the start of the first stage of destruction 

 (mechanical). 



3 points - Large quantity of snow puddles and some drain holes present. The edges of 



the floes are rounded, often forming an ice peak which hangs over the surface 

 of the water. Ice surface is predominantly white. 



4 points - Large quantity of drain holes and snow-puddles present, joined to each other 



by rivulets. Ice surface is often similar to lace. The arches between the 

 drain holes are still white or dirty brown if there is any mineral-organic 

 sediment on the ice. In brash ice there are often found mushroom-shaped 

 floes with a noticeable list and with sub-surface "spurs" or "rams" ( taran)- 

 The smallest floes are strongly saturated with water and are gray in color. 



5 points - The ice is badly destroyed by thawing and sits deep in the water. There ap- 



pear over the water only the higher parts of the floes very saturated with 

 water and gray in color. The ice is very often seen in the form of amor- 

 phous, small fragments and it is impossible to distinguish their upper and 

 lower surfaces. In such a case there is typically present, among the separate 

 floes, a great quantity of extremely small ice chunks saturated with water, 

 these being the remnants of broken-up floes. These ice chunks are somewhat 

 reminiscent of "sludge-ice" ( kasha). In certain instances the ice retains the 

 dimensions of the large fields, thickly covered with drain-holes, similar in 

 appearance to "lace" (level ice which has its origin in the spring). With a 

 small visual angle such ice is difficult to distinguish from open water. * 



Obviously, melting commences at different dates for different regions depending on climatic 

 conditions. Generally speaking, the further north the later the date. In the case of far north re- 

 gions, the ice can pass through only a few of the phases of melting before the beginning of winter 

 cold. Thus, for example, the ice field on which the "North Pole" station was constructed in the 

 course of the summer of 1937 went through the phases of formation of thaw -water puddles on its 

 surface and flowing off of thaw-water under the ice. The ice which drifted with the Sedov in the 

 course of the summer of 1939 also went through the stages of flowing off of thaw-water from the 

 snow-puddles, draining, and new ice rising to the surface. 



The most decisive of the above-enumerated phases in the thawing process are: appearance on 

 the ice fields of the first water puddles, breaking of the large ice fields into smaller fields, and the 

 first movements of the ice. The earlier these phases occur in any particular region of the sea, the 

 earlier will occur the complete disappearance of the ice, other conditions being equal. At least, a 

 decrease in ice area will occur sufficient for navigation purposes. The importance of these phases 

 is determined by the oft-emphasized fact that while the snow and ice are the most perfect reflectors 

 of radiant energy, water is an extremely effective absorber of it. 



LITERATURE: 62, 77, 88. 



*The above scale was worked out before the actual navigation of 1943. It has not yet been 

 verified in practice and therefore cannot pretend to precision and accuracy. 



297 



