inside would continue to rise up. But even if this process could be 

 realized as a practical proposition, it is doubtful if the quantities of 

 water which could be raised could ever be great enough to have 

 more than a purely local effect. It would also have to operate for 

 several years to produce any effect in terms offish we could catch. 



An ability to forecast the "weather" of the sea would bring enor- 

 mous savings to merchant shipping of all kinds, including fisheries. 

 For instance, the success of the Arctic cod fishery around Bear 

 Island depends largely on the climatic functions of both the sea and 

 air. Far more than the land, the oceans absorb and retain great 

 quantities of heat, which the currents carry from one part of the 

 earth to another. Most of the radiant energy from the Sun is in the 

 form of short-wave radiation absorbed only in small amounts by 

 the atmosphere, but in large amounts by the land and sea. The sea 

 and land reflect this energy into the atmosphere as long-wave 

 radiation which the air can absorb ; so much of the heating of the 

 atmosphere is directly dependent on the sea. The ocean currents 

 are, therefore, an important factor in climate. As we come to learn 

 more about the movements of currents, and about the interchange 

 of energy between air and sea, we will inevitably come to a better 

 understanding of climate change. 



Considering that the sea covers the greater part of the earth's 

 surface, it would be difficult to overstate its future use to men. In 

 this brief conclusion it has been possible to mention only a few of 

 the ways the sea can be made to serve us. Our present knowledge 

 of large parts of the oceans is hopelessly inadequate, and it is only 

 within the last decade or so that we have begun to understand some 

 of the processes taking place in the sea. 



Map on the following pages shows relative 

 fertility of different parts of the oceans. 

 In general the most fertile areas are found 

 in higher latitudes, but one exception is 

 found along the west coasts of continents 

 In tropical latitudes. Here deep water rises 

 to the surface, bringing with it nutritive 

 salts for the plankton population. The deep 

 shadows along the eastern sides of the 

 continents, and on the eastern slopes of 

 rises on the sea floor, are related to 

 topography, as are the deep shadows 

 indicating mountains on the land. These 

 darker areas are not intended to represent 

 regions of greater fertility. 



Since 1932 the Dutch have reclaimed from the 

 sea thousands of acres of land. These 

 photographs show what was once the Isle of 

 Schokland, but which Is today a long, low 

 hill surrounded by cultivated land. When 

 the reclamation plan Is completed the 

 Dutch will have won from the sea more 

 than a half million acres of new land. 



243 



