trees, not snags or retrogressed sites. The serv- 

 ices industry likewise benefits from contented 

 tourists. The well-being of the wildlife resource 

 depends upon healthy forest environment under 

 adequate protection. A period of 40 to 100 years 

 is often required for caribou and reindeer range 

 to recover from fire. Fur quality is much reduced 

 in burned-over country. Many of the Nation's 

 duck and geese originate in Alaska; destruction 

 of their eggs and nesting grounds reduces the 

 hunting potential in the western half of the 

 United States. 



Mining operations, still important in Alaska, 

 must have a constant flow of water, with neither 

 flooding nor drought, for their ventures to be 

 economically successful. Interested potential in. 

 vestors tend to shy away from establishing busi- 

 ness or industry where a continuous source of 

 raw material cannot be reasonably assured and 

 protected. Well-cared-for watersheds are neces- 

 sary for all resource development and mainte- 

 nance. Aircraft use for defense, profit, or pleas- 

 ure requires smoke-free skies. Airborne fire con- 

 trol operations in particular cannot succeed when 

 the sky is full of smoke. 



No reliable means of determining intangible 

 loss from fire has yet been developed. Even the 

 full impact of fire on tangible assets of timber, 

 forage, and improvements is sometimes difficult 

 to ascertain. Research and development must be 

 aimed at establishing and maintaining standards 

 of fire control commensurate with the needs for 

 industrial, recreational, and personal security. 



Alaska's 586,000 square miles make it by 

 far the largest State in the Union. Geographi- 

 cally, the peninsula of Alaska varies from a 

 southern coastline of precipitous ice-packed 

 mountains, to vast flood plains along the Bering 

 Sea, to extensive interior valleys separated by 

 rolling hills. The State can be divided by geo- 

 graphic formations into seven distinct divisions. 

 Southeastern Alaska lies along the coast south- 

 east of longitude 1 41 W. to the end of American 

 ownership south of Ketchikan. The Alaska Range 

 separates Cook Inlet, Copper River, and South 

 Coast Divisions from the others and confines 

 them to the maritime climatic influence. West 

 Central and Bristol Bay Divisions are made up of 

 hills and broad flood plains and open out onto 

 the Bering Sea. The Brooks Range separates the 



Arctic Drainage Division from the rest of the 

 State. The broad valleys of the landlocked In- 

 terior Basin embrace most of the Yukon, the up- 

 per Kuskokwim, and the Tanana River drainages. 



The movement of high and low pressure 

 systems over the northern Pacific and the Alaskan 

 mainland areas influences the climatic conditions 

 experienced in the several climatic regions of 

 Alaska. Summertime heating of the land surface 

 of the interior under the influence of long days 

 causes a relatively low pressure while pressure 

 builds up over the cool waters of the North Pa- 

 cific. As a result, weather becomes warm, some- 

 times hot, with occasional rains. Climatically, 

 the State is divided into four general zones: the 

 Maritime Zone consists of the coastline from 

 southeastern Alaska through the Aleutian penin- 

 sula; the arc farther inland, but extending along 

 the Bering Sea, constitutes the Transition Zone; 

 the great Interior Basin is called the Continental 

 Zone because of its definite continental climatic 

 characteristics,- and the Arctic Drainage Zone is 

 one of dominant Arctic influences. 



Climate of the Maritime Zone is character- 

 ized by small variations in summer temperature, 

 high humidities, high fog frequency, consider- 

 able cloudiness, and abundant precipitation. The 

 Transition Zone receives considerably less pre- 

 cipitation than the Maritime Zone. Thunder- 

 storms are common in the Copper River portion. 

 Winds in this zone are generally light, but locally 

 strong and erratic. The Continental Zone is set 

 apart from the others by topographic barriers. 

 Summertime temperatures may reach into the 

 high 90 s; annual precipitation in some localities 

 is as little as 6 inches. The Arctic Zone is not 

 important to fire control activity. Precipitation 

 and temperature are both low. Average wind- 

 speeds, however, are relatively high. The sun's 

 rays in this extremely high latitude cause little 

 surface heating. 



Data from 18 weather stations throughout 

 Interior Alaska were analyzed for the period 

 1950-58 to determine the weather regimes under 

 which fires burn and control action is taken. 

 Precipitation generally decreases from the south 

 to the north and increases from April through 

 August. Average afternoon temperatures in- 

 crease and relative humidities decrease from the 

 Anchorage area northward towards the Fa i r- 



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