The General Geography of Alaska 



189 



complete if it did not include the amount 

 of sunshine and cloudiness, since these 

 are important factors in the growth of 

 ^lant life. At Sitka it is cloudy two- 

 thirds of the time, and nearly half of the 

 time it is raining or snowing. At Kadiak 

 the conditions are a little better ; at Una- 

 laska they are worse, for Unalaska is 

 unrivaled for bad weather. , Only 8 days 

 in the year during several years of rec- 

 ord were entirely clear and only 45 

 partly clear, the remaining 312 being 

 cloudy, and 271 of those were rainy or 

 snowy. 



' Before attempting to explain these pe- 

 culiarities of climate, it should be stated 

 that the sea commonly produces two 

 modifications of temperature. It may 

 reduce the extremes, making the atmos- 

 phere cooler in summer and warmer in 

 winter, and it may reduce or increase 

 the mean annual temperature. The 

 Pacific coast of Alaska is within the 

 range of the prevailing westerly winds of 

 the northern hemisphere. These winds 

 come off the ocean, bringing to the coast 

 the temperature of the sea. As the sea 

 absorbs heat slowly, in comparison with 

 the land, and parts with it as slowly, 

 the winds blowing off it are cool in sum- 

 mer and warm in winter. Moreover, 

 since the ocean has waves, tides, and 

 currents, by which its waters are moved 

 about, the cold water of the north to- 

 ward the south and the heated water of 

 the tropics toward the north, there is a 

 tendency to establish an equilibrium of 

 temperature. Thus the northern seas 

 are warmer, on the whole — that is, the 

 mean annual temperature is higher — 

 than land in the same latitudes, and 

 through the agency of the westerly 

 winds the coast shares in this ameliora- 

 tion of temperature. 



These same westerly winds are re- 

 sponsible for another feature of the cli- 

 mate, the heavy rainfall. Thej" come 

 from the sea saturated with moisture, 

 and if they find the land colder than 

 they are, as it is in fall and winter, they 

 are chilled below the point of saturation 

 and disgorge copiously ; but if they find 



Photo ty Curtis 



An Indian Totem 



