— 17 



APPENDIX A; PETTERSSON 



The period 1902 — 1903 affords an excellent instance of this, that winter, as everybody 

 knows, being noteable for its warm and stormy weather. The cause of this was the 

 intense activity developed by the centre of the barometric depression in the North Atlantic. 



It is not my intention in this paper to deliver any opinion on the ultimate cause 

 of the connection of hydrographie and météorologie phenomena. My present purpose 

 is only to discuss the relations found to exist in the manifestations of both. 



As already mentioned the flooding of the Atlantic current in the period 1902 — 1903 

 culminated later than usual. December 9''' to February 10* the temperature in 200 m. 

 depth at Sc 8 fell but o-°6^ ^. This slight apparent loss of heat suggests a more aboun- 

 dant supply of water from the Atlantic current than usual. 



In the course of winter this salt and warm water is carried northwards into the Warmwater- 

 Norwegian Sea, where in lat. 70° it formed a surface-layer of great magnitude. The ^'^^^^'^^^^ ^g J"^" 

 deepsoundings of the Norwegian cruiser Michael Sars, February 1903, show, that in 1902-1903 

 70° lat. this layer extended from the iceborder about 4°3o' long. W to 11° long. E. East 

 of the O meridian the thickness of this layer was found everywhere to exceed 500 m. 

 the temperature varying from + 3° to +4°C. ; at the surface the temperature ranged between 

 + 4°'38 and -|- é°-05 C. The accumulation of warm water caused the iceborder every- 

 where to recede considerably. In the surfacewater atlantic plankton was found every- 

 where between the 69°''' and 70°''' lats., even among the drifting icefloes near Jan Mayen ^. 

 A host of climatic and biologic phenomena accompany the anomalous hydrographie 

 conditions of the winter 1902 — 1903. Among these we need only mention the mild 

 and stormy character of the weather, the postponement of the spawning-period of the maiies in the 

 cod, the postponement for more than 2 months and partial failure of the Lofoten cod- 

 fishery and the migration along the Norwegian coast of arctic animals such as seals 

 (Phoca groenlandica and annulata) and the white whale (Delphinapterus leucas). Specimens 

 of these were found in the veiy harbour of Christiania. 



The following winter the flooding commenced earlier. This is evidenced by the 

 large increase in the heatstore during August — November of the 200 m. layer at Sc. 8 

 and of the 60 m. layer at S Skag. 8 (see table pag. 15 and diagram fig. 11). The Norwegian 

 Reports also contains a statement to the effect, that the temperature and salinity of the 

 southern Norwegian Sea already in November 1903 were relatively high, and that plankton 

 of southern origin abounded there. The hydrographie conditions of this year approach 

 nearer to the normal state than those of the previous year. The climatic conditions of 

 both years differ too. A glance at the accompanying synoptic charts (Fig.12, p. 18) representing Barometric 

 the weather of the true winter-months, January, February, March of 1903 and 1904 will ™he winter 

 show this to be the case. The accumulation in high lats. of warm water during 1902 — i903 and 1904 

 1903 acted as recruiting ground for cyclones and barometric depressions. The trend of 



J Were it possible to compare the heat total of the water column from surface to bottom (350 m. 

 in December and in February (which is not practicable on account of the heterogeneity of the surfitce- 

 layer) the result would give an increase of 52875 calories in the heatstore of tlie water. 



2 See the description in the Norwegian annual report 1902— 1903, p. 4. by Dr. Hjort in; Aarsberetning 

 vedkommende Norges Fiskerier. i Heft. 1903. The author states, that among this southerly plankton of 

 the surface specimens were found of such plankton as in summer only inhabit the deep regions (the 

 boundary layer of Arctic and Atlantic waterj, among these he mentions Boreophausia and Nyctiphanes. 



3) See the Norwegian Report for 1904, Heft i, p. 95. 



Anlag« .\ ^ 



Climatic and 

 biologic ano- 



winter 

 1902-1903 



