This summer's large wildfires come a year after more than 6.5 million acres (2.6 million hectares) burned last year, the most since wildfire records have been kept in the past 56 years.
The two consecutive large fire seasons are unprecedented, according to wildfire managers and forestry experts.
"It does not happen, until recently, that we have two large back-to-back fire seasons," said Maggie Rogers, spokeswoman for the Alaska Interagency Coordination Center, the consortium of federal and state agencies that manage wild fires in Alaska.
Within a week, this year's total is expected to surpass the 1969 total of 4.017 million acres (1.63 million hectares), the third-largest on wildfire season on record, Rogers said.
The large reach of this year's fires may be one sign of a major climate-driven change underway in Alaska's boreal forest, said Glenn Juday, a professor of forest ecology at the University of Alaska Fairbanks.