2020 California wildfires
The 2020 California wildfires marked an unprecedented disaster in the state's history, characterized by approximately 10,000 fires that scorched over 4.2 million acres, which is about 4% of California's total land area. This catastrophic season included the August Complex fire, the largest in California’s recorded history, which alone consumed over one million acres. The wildfires resulted in the tragic loss of 33 lives and caused damages estimated between $7 billion and $13 billion. California’s unique geography and climate, along with human influence and climate change, have contributed to the state’s fire susceptibility.
While occasional wildfires are a natural component of the region's ecosystem, human activities, including downed power lines and improper disposal of materials, have exacerbated the risks. The situation was worsened by dry, strong winds and drought conditions, which were prevalent during the summer months. The fires not only devastated the environment, leading to significant carbon emissions and ecosystem disruption, but also had lasting impacts on the mental and physical well-being of residents due to deteriorating air quality. Nonetheless, the 2020 wildfire season prompted important discussions about fire management and the urgent need to adapt to the challenges posed by climate change.
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2020 California wildfires
The 2020 California wildfires were the most devastating outbreak of forest and brush fires in the modern history of the state. In the course of the year, California was hit by around 10,000 wildfires that burned more than 4.2 million acres, or about 4 percent of the state’s total land area. One of those fires, the August Complex fire, was the largest fire in the state’s history, burning more than one million acres on its own. In total, five of the top ten largest fires in California’s history occurred during the 2020 wildfire season. The fires left thirty-three people dead and caused damages estimated to be in the billions of dollars.
Background
California’s geography and climate have always made it a fire-prone region. Most of the state’s rainfall comes in the fall and winter, meaning its forests and vegetation spend much of the warm, arid spring and summer slowly drying out and turning into fuel. Occasional, naturally-occurring wildfires are a normal part of the region’s ecosystem, with many trees and plants needing to be removed by periodic blazes to enable new growth. However, humans have been interfering with this cycle since the early twentieth century by becoming more effective at fighting and preventing wildfires. While it sounds contradictory, by successfully preventing fires, humans have allowed more brush, dead twigs and branches, and dried-out vegetation to remain behind as fuel.
To compound matters, climate change has intensified the problem. Higher temperatures dry out the fuel even more quickly; these conditions are made even worse during droughts, which California has experienced frequently in the twenty-first century. With the overabundance of more combustible fuel, the slightest spark can ignite a potentially devastating blaze. While lightning or other natural occurrences can spark wildfires, most of the time, human actions are to blame. Downed power lines have started many of the state’s wildfires, as have carelessly discarded cigarettes and fires that spread from homeless encampments. A 2018 fire that left eight people dead was started when a truck suffered a flat tire, causing sparks from the rim, hitting the road to ignite nearby brush. The 2020 El Dorado fire that charred more than 22,000 acres in Southern California was caused by fireworks from a gender-reveal party.
Another factor that contributes to California’s wildfire problem is the dry, warm wind that blows in from the east. In southern California, the winds are known as Santa Ana winds and are caused by high-pressure systems over the Great Basin and upper Mojave Desert. The high pressure forces the warm air westward, where it streams into Southern California. In Northern California, warm, dry winds blow west off the Sierra Nevada Mountains, forming what are known as Diablo winds. Both can produce gusts of up to 80 miles per hour (129 kilometers per hour) that can quickly spread flames over a wide region and cause sparks and embers to ignite new areas.
Overview
Although January and February were dryer than normal in California, steadier rains in March and April limited the number of wildfires in the state to relatively normal levels through the first half of the year. Several significant fires erupted prior to August, with the largest charring about 144,000 acres in the northernmost part of the state. However, California and all the western United States were still experiencing drought conditions, and the risk of fire remained high.
In mid-August, a storm moved into California from the Pacific, raising hopes that it would provide rain to mitigate the fire risk. However, the precipitation from the storm was limited to the upper atmosphere and never reached the ground. Instead, the storm produced an estimated 15,000 lightning strikes, igniting numerous fires across the state. In some cases, smaller fires merged, forming larger blazes known as complex fires. The fires were whipped along by strong Santa Ana and Diablo winds. California’s governor, Gavin Newsom, declared a state of emergency and reported that about 367 fires were raging in the state.
One of the large wildfires caused by the storm erupted when a cluster of fires merged together in California’s wine country, north of San Francisco. The blaze, which was given the name the LNU Lightning Complex fire, burned in the hills surrounding several large towns, including Napa, Fairfield, and Vacaville. The fire forced the evacuation of more than one hundred thousand people. Before it was extinguished in early October, the LNU Lightning Complex fire burned 363,220 acres, destroyed almost 1,500 structures, and killed six people. In the mid-2020s, it remained the sixth-largest fire in California history.
Another large fire, dubbed the SCU Lightning Complex, also erupted near San Francisco and in the counties south of the city in mid-August. Although the fire burned 396,224—the fourth largest in state history—it was in a more remote area. It destroyed only 222 structures and did not result in any fatalities. The North Complex fire began on August 17 in Northern California’s Plumas National Forest and was briefly considered to be under control before high winds fueled its expansion in early September. The fire burned until December, destroying the towns of Berry Creek and Feather Falls and killing fifteen people. It was the deadliest blaze of the 2020 wildfire season and the seventh largest in state history, burning 318,933 acres.
The Creek fire began in the Sierra National Forest near Fresno in September. Although the cause of the fire remained under investigation as of 2021, fire officials believe it was also caused by lightning. The fire burned 379,895 acres—the state’s fifth largest—and destroyed 853 structures. No deaths were reported from the fire.
The largest fire of the 2020 wildfire season, and the largest fire in California’s history, was the August Complex fire, which charred more than one million acres in a six-county region north of San Francisco. The fire resulted from the merger of more than thirty smaller blazes in mid-August. At its greatest extent, the fire was larger than the state of Rhode Island. The August Complex fire raged until November, destroying 935 structures and resulting in the death of one firefighter.
As the fires burned through August and into the fall, they sent large plumes of smoke into the atmosphere. The smoke drifted eastward, where it resulted in hazy skies and poor air quality across much of the United States. By year’s end, the 2020 California wildfires had destroyed 4.2 million acres and left thirty-one people dead. Among those killed were three firefighters. Damage estimates from the fires range from $7 billion to $13 billion.
In addition to death and destruction, the 2020 California wildfire season had many lasting effects. Environmentally, the fires damaged forests and disrupted ecosystems. The fires drastically increased the level of carbon emissions in the air. Not only was the physical health of residents affected by the decline in air quality, but the 2020 fires also significantly affected the mental health of Californians. The 2020 fires devastated California economically due to property damage and damage to agriculture. Conversely, the 2020 California wildfire season led to many beneficial fire prevention and management changes. It also underscored the importance of recognizing the destructive possibilities associated with global climate change.
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