PETTERSSON— INTRODUCTORY 



IV — 



Surface chart, August 1896 



Atlantic water 



. ~ r Arctic water 

 Fig. 2 



Coastal and bank water 



layers and under-currents in the Norwegian Sea. The Atlantic origin of these 



under-ciirrents intermediate layers is detected, on making hydrographical soundings, by a maximum 



of temperature and salinity suddenly appearing in depths of 6o— 300 ml. jj, tijjg 



I The surface chart shown in Fig. 2 is the first which has been constructed on simultaneous 

 observations in the northern Atlantic Ocean, the North Sea, and Norwegian Sea. (See, Petermann's 

 Mitteil. 1900. Heft I und II). The area of the Atlantic surface water varies greatly in different 

 years and seasons especially so in the border regions (See, Appendix A). It seems to have reached 

 a maximum in 1896, to judge from our present knowledge. 



