9 — 



APPENDIX A ; PETTERSSON 



plateau east of Shetland extends northwards over tjie deep region of the Norwegian Sea. 

 The diagram is constructed from deepsoundings made at the same stations in June and 

 in September 1899 by the'Swedish expedition to Greenland. 



The shaded area represents a cross-cut section through the core of the current, the 

 salinity of which exceeds 35-25 "/oo. From June to September a powerful expansion of 

 this core had taken place, as is shown by the figure. 



From the following charts (Fig. 6, p. 10) it appears, that the annual fluctuation of the variations in 



1 • ,..,.,.'..., ^ ,^ . . ^ , the Gulfstream- 



northern seas m reahty is due to periodic variations m the Gulfstream-circulation of the circulation 



eoMa. 



Fig. 4. Section of tlie Atlantic current, May— June if 



Fig. 5. Section of the Atlantic current, September 1899 



Atlantic. Preliminary to the international exploration an investigation ' was carried out tor 

 one entire year (1899) regarding the variations in salinity, temperature, and plankton of the 

 surface-layer of the North Atlantic. The accompanying surface charts give the position 

 of the areas of 36 "/oo and ^y^/oo salinity. The Gulfstream-circulation proper formes an 

 eddy surrounding a sargasso-sea. In March this eddy touches the Azores. The area 

 between the Azores and the African coast is during this season filled with colder water 

 of less salinity. In November and December the area of Gulfstream-water has expanded 

 in a north-easterly direction towards the coasts of Africa and Southern Europe. The area 

 of tropic (Desmo-) plankton has done Hkewise. During the first months of the year the 

 Gulfstream-area contracts, regaining its most westerly position in March. 



As final proof of the ebb and flood of the Atlantic current the following diagrams Annual tiuctu- 

 (Fig. 7, p. 11) are given. They are derived from the latest publications of meanvalues of 



ations in 

 the waterievel 



I Cleve, Ekman ct Petter.s.son , Les variation.s annuelles de l'eau de surface de l'océan ,\tlautique. 

 Appendix A 



