NO. 4 TEMPERATURE VARIATIONS IN THE NORTH ATLANTIC II7 



to negative anomalies in the surface temperature as our charts, 

 plates 27 and 29, also show. We find, nevertheless, from the curves 

 in figures 48 to 52 that the negative anomalies corresponding to 

 the air pressure gradients in several fields were not so great that 

 they would produce great negative anomalies in the surface tem- 

 peratures. Furthermore it is also notable that the course of the 

 variations of the curves for the anomalies of the air pressure gradi- 

 ents from field to field in plate 28 is entirely different from the 

 course of the variations of the curves of the anomalies of the sur- 

 face temperature and the air temperature. 



If we take also into consideration that over great regions of the 

 earth not only the temperature of the ocean, but also of the air 

 exhibited considerable negative anomalies (compare what has been 

 said and also the chart pi. 28) , we must come to the conclusio'n that 

 reactions were going on here which were due to other causes than 

 the local winds ; more accurately stated, we may conclude that the 

 negative anomalies of the air pressure gradients which we have 

 found over the whole of the investigated region are due to the same 

 causes as the low temperature of the ocean surface and the air 

 over the greatest part of the earth. 



If we consider the Dutch material for the two earlier mentioned 

 10° squares further south, we find that in these two fields the 

 temperatures of the ocean surface was a minimum in February, 

 1904, while on the other hand the direction and strength of the 

 wind in January to February was not of the kind to bring on such a 

 minimum. It must be remembered however, that the number of 

 observations in these great fields was very small. 



We find besides that in a number of stations, particularly in the 

 tropical regions, the temperature of the air for 1904 was uncom- 

 monly low and in many places a minimum. As noted by Arctowsky 

 (1912) the reverse of this is found for several regions of the earth. 

 For example, in Honolulu, Bombay, and the most westerly United 

 States there was a maximum of temperature in this year. 



This most probably indicates peculiar conditions of the distri- 

 bution of the air pressure over the earth's surface, which also 

 depended upon general causes. These, however, produced opposite 

 effects both on the air temperature and the water temperature in 

 different regions. As we shall notice later, there appears to have 

 been on the whole a minimum air temperature over the whole earth's 

 surface in the year 1904. 



