IV-520 



Alaska Estuarine Region : All of Alaska including the Aleutian 

 and Bering Sea Islands. 



The dominant factors in this region are temperature and precipita- 

 tion. Water temperatures are near freezing, and much of the 

 precipitation falls as snow. The continental shelf is wide all 

 through the region, and tide ranges are very large. The southeast 

 and south coasts have active glaciation and consist primarily of 

 glacier-cut embayments and fjords; the west and north coasts are 

 much flatter and have been modified to some extent by sediments 

 eroded from the interior, including glacial silt, and by the grinding 

 action of pack ice during winter. 



Pacific Islands Region : The Hawaiian Islands, American Samoa, 

 and Guam. 



This region consists of tropical ocean islands of volcanic origin. 

 Dominating factors are lack of a continental shelf, full exposure 

 to oceanic conditions, and pleasantly warm tei*>eratures . Coral 

 reefs and beach and bluff configurations are typical. 



THE LAND AND THE WATER 



Within the general domination of broad-scale environmental factors 

 are smaller scale governing conditions that, through their effects 

 on water movement and circulation, determine what kind of local 

 environment can exist in a particular estuarine system. 



