CHAPTER I 
EXISTING GLACIERS 
GENERAL DISTRIBUTION 
Nearly all the glaciers of Alaska are comprised within 
a belt of moderate width which follows the southern coast 
from the Aleutian Islands to Portland Canal (see fig. i). 
Curving about the great bight of the Pacific Ocean known 
as the Gulf of Alaska, this belt has a length of 1,600 miles, 
and its extreme width, near the middle, is about 250 miles. 
Within it the arrangement of glaciers is irregular, but their 
more important groups occupy the middle region, while 
near the ends they are comparatively sparse and small. 
The explanation of this massing of glaciers along the 
southern coast is not far to seek. The general circulation 
of the Pacific Ocean brings to the Gulf of Alaska a cur¬ 
rent of water which has been warmed in the tropics and 
still retains so much heat that its mean temperature is 
considerably above the normal for the latitude. The 
ocean is therefore, at most seasons, warmer than the con¬ 
tiguous land, and though air currents passing from ocean 
to land convey heat to the land they are themselves cooled. 
( 7 ) 
