Īt 1:30 p.m., a PG&E troubleman (a type of lineworker) came to address the resulting power outage. Electric arcing slowly ignited fuels on the ground over the following hours. The tree, in contact with both the line and the ground, created an electrical fault. When the tree fell onto the line, two fuses blew but one remained active, keeping the power line energized. Why the tree fell is unknown-an arborist with Cal Fire said the tree was weakened after burning in the 2008 Butte Lightning Complex, while another arborist hired by PG&E noted possible root rot. a large Douglas fir, 65 feet (20 m) tall and 16 inches (41 cm) in diameter, fell onto the power line. Transmission lines (also operated by PG&E) further down the canyon were the cause of the devastating and fatal Camp Fire in 2018. The Dixie Fire began on July 13, 2021, beneath a Pacific Gas and Electric (PG&E) 12-kilovolt power distribution line located on the northern side of the Feather River Canyon in a remote area above Highway 70 and Cresta Dam, midway between Paradise and Belden. Bark beetle-affected forests (especially species common in the Sierra Nevada such as the lodgepole pine) are chemically altered, and the dead and dying trees are more flammable and more susceptible to intense crown fires. The resulting overcrowded forests became more vulnerable to drought, as well as bark beetle infestations that were the primary cause of death for more than 163 million trees in California between 20. Rigorous fire suppression policies in the United States also meant that much of the area burned by the Dixie Fire had little fire history, going back more than 40 years.

Reservoirs in the state shrunk, and vegetation dried out to the point where both living and dead conifers were drier than kiln-dried lumber. The Sierra snowpack, measured during its typical peak on April 1, was just 59 percent of the historical average, and runoff just 20 percent of the amount forecast. That year also saw further intensification of what scientists have found to be the most extreme megadrought in at least 1,200 years in the Western/Southwestern United States, amplified by high temperatures, low precipitation, and anthropogenic climate change: during the 2021 water year (the period between October 1, 2020, and September 30, 2021), Northern California received less than half of its usual precipitation. 2021 was the hottest summer ever recorded in California. Background Ī number of factors contributed to the size and intensity of the Dixie Fire. The Dixie Fire was the most expensive wildfire in terms of suppression efforts in United States history, costing $637.4 million to fight. Smoke from the Dixie Fire caused unhealthy air quality across the Western United States, including states as far east as Utah and Colorado. It was the first fire known to have burned across the crest of the Sierra Nevada (followed by the Caldor Fire later in the season). The Dixie Fire was the largest and most destructive fire of the 2021 California wildfire season. non-complex) wildfire in recorded California history, and the second-largest wildfire overall (after the August Complex fire of 2020), The fire damaged or destroyed several communities, including Greenville on August 4, Canyondam on August 5, and Warner Valley on August 12. Named after a nearby Dixie Road, the fire began in the Feather River Canyon near Cresta Dam in Butte County on July 13, 2021, and burned 963,309 acres (389,837 ha) before it was declared 100 percent contained on October 25, 2021. Totals are calculated using 2020 nighttime estimates from the Landscan, a population database generated by Oak Ridge National Laboratory.The 2021 Dixie Fire was an enormous wildfire in Butte, Plumas, Lassen, Shasta, and Tehama counties in Northern California. The quality levels are based on the Air Quality Index developed by the U.S.

Readings have been adjusted to account for the properties of wood smoke.

Colored squares show levels of particulate matter in the air that average 2.5 microns or smaller in diameter where sensor data is available within a 10-mile radius of each square’s position. The exact boundary of a fire may differ from the extent shown on the map by 500 meters or more.Īir quality data is derived from PurpleAir sensors. Areas marked in red indicate where active burning was detected within 24 hours of the most recent fires reflected on the map. The locations of the fires on the map are approximate, derived from data reported by the NASA FIRMS satellite-based fire detection system, which makes observations several times a day. The map includes active and recent fires reported by the Wildland Fire Interagency Geospatial Services Group.

California fire maps