CHAPTER 3 



GEOGRAPHY AND CLIMATE 



From a fire control standpoint Alaska, like 

 most western States, has some portions that are 

 considered easy, some moderate, and some criti- 

 cal. What makes one area easy and another criti- 

 cal? Usually considered pertinent to this ques- 

 tion are the following factors: (1) The geographic 

 arrangement of the land in relation to elevations 

 and general weather patterns, (2) climatic con- 

 ditions, which are generally influenced by the 

 geographic pattern, (3) weather patterns on a 

 local and short-term basis, and (4) fuels, as in- 

 fluenced by all the above factors. Fuels are dealt 

 with in a separate chapter (ch. 4). The first two 

 factors are described in rather general terms to 

 help set the stag^ for more specific information 

 that follows in the remainder of the publication. 



PHYSICAL GEOGRAPHY 



Alaska is by far the largest of the 50 States 

 — a vast expanse of land lying north of the Pa- 

 cific Ocean, separated from the larger land mass 

 of Siberia to the west by Bering Strait and joined 

 along the 141st meridian on the east to Yukon 

 Territory, Canada. Alaska contains 586,400 

 square miles (375,296,000 acres); about one-third 

 of this acreage is in the Interior Basin. Geo- 

 graphically, Alaska is divided into seven areas 

 — South Coast, Copper River Valley, Cook Inlet, 

 Bristol Bay, West Central, Arctic Drainage, and 

 the Interior Basin as drawn in figure 19. 



SOUTH COAST 



The Aleutian Islands and Southern and 

 Southeastern Coastal Areas combine to form a 

 1,500-mile crescent-shaped coastline,- at some 

 points it is 120 miles in depth. At its eastern 

 extremity this area is mountainous, cut by a 

 great number of tidewater bays, sounds, inlets, 

 and fiords. Huge glaciers descend the mountain 

 passes and often flank these shoreline indenta- 

 tions. AAountaintops are above 5,000 feet and 

 several rise to heights of 10,000 to 15,000 feet. 

 The precipitous slopes of the mountains from 

 Kodiak Island eastward are mostly clothed to 

 heights of 1,000 to 3,000 feet by dense stands 

 of spruce, hemlock, and some cedar. The Alaska 

 Peninsula and adjacent islands southward from 

 Kodiak Island are devoid of forests, but are cov- 

 ered with luxuriant growth of native grasses. 



About half of southeastern Alaska consists of 

 islands. Prince of Wales Island — the largest 

 — is 140 miles long by 40 miles wide. The 

 largest fresh-water streams in the area are the 

 Stikine and Taku Rivers, which rise in British 

 Columbia. 



COPPER RIVER VALLEY 



Copper River Valley is surrounded by four 

 mountain ranges varying in height from 4,600 

 to 17,000 feet. The Alaska Range forms the north 

 boundary, St. Elias the east, Chugach the south, 

 and the Talkeetna Range the west. Copper River 

 Valley is nearly 120 miles long and up to 50 

 miles wide. Icefields and glaciers are the main 

 sources of water for the Copper River. The basin 

 is a high plain with elevations as great as 

 2,500 feet above sea level. This valley is dotted 

 with numerous lakes surrounded by stands of 

 spruce and birch timber. Many areas within the 

 valley are covered by dense stands of native 

 grass and tundra species. 



COOK INLET 



Cook Inlet Division embraces most of the 

 Kenai Peninsula, the famous AAatanuska Valley, 

 and the delta of the Susitna River. It is bordered 

 by the Alaska Range, and the Talkeetna and 

 Kenai Mountains. Elevation of the valley floor 

 varies from sea level to about 2,500 feet. Vege- 

 tation varies from rather luxuriant grasses and 

 some spruce and hardwoods on the Kenai Penin- 

 sula to heavy stands of spruce and some very 

 fine birch in the central and northern portions of 

 the Division. 



BRISTOL BAY 



Bristol Bay Division, nearly 500 miles long 

 by 180 miles wide, drains into the Bering Sea. 

 The Kuskokwim River is the largest river that 

 drains this area. 



The coastal and valley portion is undulating 

 to rolling,- its elevation varies from sea level to 

 nearly 2,000 feet. It is studded with hundreds 

 of lakes and potholes. On the northwest the 

 zone is bordered by the Kuskokwim Mountains 

 and on the south and east by the Aleutian Range. 

 These mountains vary from foothills to precipi- 

 tous peaks nearly 9,000 feet high. 



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