NO. 4 TEMPERATURE VARIATIONS IN THE NORTH ATLANTIC 



405 



Jahr 



III I IV 



VI VII i VIII I IX X I XI I XlljSummel Mittel 



93 

 94 

 95 

 96 



97 

 93 



99 

 1900 



03 

 04 



05 

 06 

 07 

 08 



54 

 67 

 43 

 35 

 25 

 53 

 31 

 29 

 26 



3 



3 



12 



23 



24 



42 



50 

 43 



56 

 37 

 42 



33 

 33 

 41 

 24 



25 

 22 



9 

 9 

 15 

 23 

 32 

 33 

 28 



43 



33 



4 

 55 

 17 

 49 

 23 



33 



67 

 51 

 39 

 44 

 55 

 45 

 41 

 20 



13 



13 

 30 

 20 



3 

 40 

 16 

 39 

 19 

 12 

 4 

 3 

 52 



729 

 618 



558 



40a 



481 



558 



397 

 255 

 163 



87 



49 



142 



327 

 354 

 294 

 522 

 416 

 439 

 315 

 184 



137 

 117 



424 



61 

 52 

 47 

 34 

 40 

 46 

 33 



2t 



"4 



7 



4 



12 

 27 

 30 

 25 



44 

 35 

 37 

 26 



15 



35 



EXPLANATION OF PLATES 



Plates 1-14. — Surface temperature in degrees Centigrade of the 2° longitude 

 fields for all of our observational region for each year 1898 to 1910 

 and each decade group (February 3 to March 4, plates 1-7, March 15 

 to April 13, plates 8-14). The small numbers at the top on the left 

 for each temperature gives the number of observations in each 2° 

 longitude field and in each decade group. The isotherms for 8°, 10", 

 12°, 13°, 14°, 15°, 16° C. are indicated. 



Plate i, figure i. — The mean temperatures for the first decade group (Feb- 

 ruary 3 to March 4) for the years 1900 to igio in the 2° longitude 

 fields of the shipping route Channel to New York and in the 10° 

 longitude fields of the region Portugal to the Azores. The arrows 

 give the mean isobar directions and mean strength of the air pres- 

 sure gradients for the 10° longitude fields in the years i8g8 to 1908. 



Plate 7, figure i. — The mean temperatures for the second decade group 

 (March 15 to April 13) for the years 1900 to 1910 in the 2° longitude 

 fields of the shipping route Channel to New York. The arrows give 

 the mean isobar directions and the mean intensity of the air pressure 

 gradients for the 10° fields in the years 1898 to 1908. 



Plate 15. — The charts : fields and stations. The separate numbers give the 



fields with the surface temperatures. The numbers surrounded by 



circles give fields or stations with air temperatures. 



Fields 1-6: The six 10° longitude fields of the route Channel to New York. 



Fields 7-18: The twelve fields of 10° longitude and 2° latitude in the 



region between Portugal and 40° west longitude. 

 Fields 19-20: The two Dutch 10° squares. 



Fields 21-24: The four 10° longitude fields for the Danish observations 

 between 0° and 40° west longitude and 50" and 60° north latitude. 



