NO. 4 TEMPERATURE VARIATIONS IN THE NORTH ATLANTIC 37 



the same observational material from the ships' log-books of the 

 Deutschen Seewarte as he did. By comparison of the temperatures 

 of the single fields which Schott gives in his charts for Februar}-, 

 1903, in plate 18, with our material, we find considerable deviations 

 (see our pi. 4 and Schott's pi. 18). Unfortunately Schott has 

 not given the number o4 observations for the single fields, but 

 since we have given among others temperatures for a whole series 

 of fields where he gives none in his charts, we must assume that 

 our material is a good deal richer than his, and on that account gives 

 more trustworthy indications. 



Besides, we believe that our process in assembling the observa- 

 tions in 2° fields is more advantageous than his assembly in 1° 

 fields, especially where the number of observations at each field 

 is so small as here. Else a single erroneous observation plays too 

 large a part. From our own material we believe that we can see 

 that in a whole series of temperature values in different fields 

 Schott has employed only a single observation. 



However, this consideration does not suffice in order to explain 

 all the dift'erence between his result and ours. For this we must 

 call attention to the fact that he has obtained his normal tempera- 

 tures for the single fields from " Ouadratarbeit " of the Deutschen 

 Seewarte, whereas we obtained our normal temperatures from 

 the reduction of all observations of the eleven-year period, 1900 

 to 1910. Furthermore, we have used for the computation of the 

 temperature anomalies only the temperature normals from the series 

 of 48 fields where we found that the number of the observations 

 of the different years was great enough so that one might expect 

 that they would really give good values. Thus we hope that we 

 have results which give a trustworthy picture of the march of the 

 distribution of temperature variations. That this is indeed the case 

 appears, as we have already remarked, since the different curves 

 show close similarity between themselves. 



According to the results which are afforded by the discussion of 

 our observation material we think that we may safely say that in 

 the time from the beginning of February to the middle of April, 

 1903. no such increase in the strength of the Gulf Stream was 

 present as Prof. Schott supposes. On the other hand, the surface 

 temperatures were in all ocean regions from 60° west and eastward 

 to about 25° west in February considerably below the normal. 

 Even in the western part of this region, that is to say, between 50° 

 and 60° west, the surface temperature of the water was uncommonly 



