Scientific position when it comes to explaining the phenomenon arctic warming 90 years ago has already been highlighted in the Introduction above. It might therefore be of interest to see to what extent the phenomenon was discussed before WWII.

One of the first scientists who highlighted the extraordinary temperature development at the ‘Green Harbour’ Spitsbergen station was the Norwegian scientist B.J.Birkeland, in 1930 (op. cit). He was very surprised of what he discovered. He finishes his brief essay with this statement: “In conclusion I would like to stress that the mean deviation results in very high figures, probably the greatest yet known on earth”.  A couple of years later, in 1936, a number of authors put Birkeland’s findings into a wider context.

(A) Johansson (op. cit., 1936) focused his investigation on the relevance of sunspots. Yet, some analytical consideration is nevertheless interesting. For example: (a) In 1919, the statistical means crosses zero-value; or, in other words, all previous years are colder; all later years are warmer; (b) Between 1917 and 1928, the increase during the summer season is of +0.9°C per 10 years, and in winter, of +8.3°C, in February, of +11.0°C; (c) It seems that the changes are coming from the North. (d) Johannsson’s main conclusion is that the increased air circulation (15 % higher) between 1896 and 1915 had gradually changed the current and ice conditions, thus altering the borders between the Arctic gulf current climate and the true Arctic climate further north.

(B) Scherhag (op. cit., 1936/8) refers to Birkeland’s work from 1930, assuming that all warming analyses have to begin with the observation of the Spitsbergen phenomenon, because only here the temperature increase was measured in the winter of 1918/19 for the first time (Scherhag, 1939); (a) There were increased Gulf Current temperatures, particularly significant in the Barents- and East Greenland Sea. (b) The extraordinary increase of the winter temperatures in Greenland (Scherhag, Nordeuropa, 1936) , was caused by a considerable retreat of the ice border and the prominent increase of the atmospheric circulation (Scherhag, ditto).
(c) Scherhag (op.cit., 1937) states that a thorough research of the temperature changes over the whole northern half of the globe during the period 1921-1930 confirmed that the largest part of the investigated region had been, indeed, considerably warmer during the decade 1921-1930. (d) Scherhag stressed: “such kind of climate changes as could now be observed in Spitsbergen and along the western coast of Greenland were certainly not restricted to a small region but must be global” (Scherhag, 1937).  (e) In his subsequent research work, Scherhag pays little attention to the natural circumstances from Spitsbergen in the late 1910s, merely acknowledging that the extent of the temperature increase would be, without any doubt, the greatest in the Arctic (Scherhag, 1939).

(C) Brooks (op.cit.,1938):  (a) The Spitsbergen branch of the North Atlantic Current has greatly increased in strength and the surface layer of cold water in the Arctic Ocean has decreased in thickness from 200 to 100 metres. (b) Attributing the recent period of warm winters to an increase in strength of atmospheric circulation (in reference to Scherhag) only pushes the problem one stage back, because one should still have to account for the change in circulation. (c) It may also be objected that the atmospheric circulation depends on the difference of temperature between low and high latitudes and, hence, should be weakened instead of strengthened by a warming in the arctic. (d) Regardless the mechanism, the rise of temperature did begin prematurely and had a cause, though it is conceivable that it arose spontaneously in the incessant kaleidoscope of temporary pressure distributions.

(D) Manley (op. cit., 1944): (a) Temperature in Norway, especially in the North, has certainly risen far more in recent years than at any other time in the last two centuries. (b) A more vigorous atmospheric circulation in the region of the Norwegian Sea would explain the observed facts, namely the recession of the ice-limit, the increased frequency of south-westerly winds, rather than south-easterly, in North Norway, and the consequent marked rise in winter temperatures which has attained its greatest magnitude in the north of the Scandinavian Peninsula.

All pre-WWII papers acknowledge the suddenness of the rise in temperatures in the North Atlantic region since the early 1920s, but pay too little attention to the location of Spitsbergen, an island in the mid of a huge sea area, with sea-ice in the north and at the edge of the Norwegian Sea in the South. However, the great-grandfathers of today’s climatologists discussed this matter very seriously and in a way, which is not very different from today.