— 15 — APPENDIX A: PETTERSSON 



the water gives off large quantities of heat by convection to the atmosphere. The values 

 for this given by the tables are, however, only apparent. In reaUty, the loss of heat of 

 the water is much greater, as the water is not stationary, and new stores of heat are 

 continually supplied by the Atlantic current. 



Besides this annual periodicity, we trace with great exactitude the effects of a non- 

 periodic disturbance. The temperature diagrams below (Fig. 10, p. 16) show the differing char- 

 acters of the years 1902 — 1903 and 1903 — 1904. In the former a postponement in the phase 

 of the flooding occurred. The heatwave probably culminated between December 1902 and 

 February following. The diurnal apparant loss of heat for the 200 — 300 m. layer was 

 36 units of heat only to 334 units in November 1903 — February 1904. The dimi- 

 nution of the heat store continued till August 1903^; 1904 the situation was reversed, a 

 strong afflux of warm and salt water then occurred , which brought up the temperature 

 from 6°78 C. (on the 2"'' of June) to 7°74 C. (on the 18''' of August), the salinity likewise 

 increasing from 35-19 %o to 35-26''/oo. 



The effect of this fluctuation of the Atlantic current upon the hydrography of the variations of 

 Skager Rak is shown in the diagram below (Fig. 11, p. 16). It gives the maximum level and 'j'n'^hT "deeper 

 temperature of the Atlantic water at the Swedish station S Skag. 8 in the centre of the iayer,<i of the 

 Skager Rak. ^"^"S" ^'^ 



The same variations observed in 200 m. depth at Sc 8 (the entrance to the Nor- 

 wegian channel) are recorded at S Skag 8 (the centre of the Skager Rak deep), the 

 Umit of the scope of the Atlantic current. At S Skag 8 too the culmination occurs 

 in November, the Atlantic water there attaining its highest level, 60 m. below the sur- 

 face, and maximum temperature 6°47 C. in November 1902 and 7°40 C. in November 

 1903. The ebb sets in in May, in August the rising again commences. The postpone- 

 ment of the heatwave in 1903 is evinced by the relatively high temperature and water- 

 level (loom.) of May 1903. 



I N.B. in the 200 m. depth of course. The water to 100 m. below the surface was licated from 

 the atmosphere in May— August. 



