172 THE OCEAN RIVER 



have come their natural food in the capehn and herring, as 

 well as haddock, halibut, salmon, and even jellyfish. Mean- 

 v^hile the more arctic forms of life, like the white whale, have 

 moved back northward. 



Fortunately many able scientists have been measuring all 

 these signs of change in the north. Wagner and Scherhag 

 tell us that from 1910 to 1930 there was a steady and constant 

 increase in atmospheric circulation, i.e., in heat convection 

 from south to north. Jensen attributes this stepping-up of the 

 climate engine over the Ocean River to the strengthening of 

 the subtropical high-pressure belt, while there has been a 

 simultaneous increase of barometric minima along the north- 

 polar front. This would cause an increased quantity of warm 

 Atlantic air to stream in over Europe and the Arctic regions 

 and bring on more oceanic or equable conditions. Coupled 

 with this is the fact — according to Slocum — that there was 

 a rise of four-tenths of a degree Centigrade in the temperature 

 of the sources of the Gulf Stream. Thus air and sea, together 

 complementing and sustaining each other, are at work today 

 causing a definite shift toward a warmer and more beneficent 

 north-temperate and Arctic climate. If this should continue 

 long enough there well might be a sudden disappearance of the 

 Arctic ice fields, and a return to the kind of climate that per- 

 sisted for several centuries when the Norse found it easy going 

 to Greenland and grains and forests grew in those lands. 



We have marked the passage of great rivers of water along 

 and below the surface, and the wind machine above them. 

 The engine of the air and the Ocean River which it drives 

 are well worth our attention, and the physical effects of wind 

 and water have their own particular grandeur. But linked to 

 them are the biological effects, the fierce and varied play of 

 life within the waters and the great sea fisheries. It is therefore 

 proper that we should turn our attention to the creatures now 

 in our seas, and to the procession of life across and around 

 the River that has resulted in the Atlantic community of man. 



