Forest fire statistics are available for the past half-century, and generally indicate that the area burned in this northernmost US state has decreased steadily while fire incidence has increased. During the 1940s Alaska recorded an annual average of 114 fires, which burned over an annual average area of 502,000 hectares. By comparison, the 1990-96 period saw annual averages of 670 fires and 383,000 hectares. Increased accessibility has influenced both fire incidence and area burned. Road and rail access meant both an increase in forest use, which resulted in increased fire occurrence, but also a corresponding enhanced detection capability and a shortened response time. Faster initial attack, particularly using smoke jumpers, coupled with aerial detection, are the major contributors to the reduction in area burned. Lightning fires, generally occurring in areas where response intervals are longer, account for a large percentage of the area burned in Alaska (38% of Alaska fires are lightning-caused and these fires account for 80% of the area burned). In addition, many fires in Alaska are fought on a priority basis, with extensive zones of limited protection, resulting in recent area burned statistics being somewhat inflated as a result of selective fire suppression.

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