5 of California's 6 Largest Fires on Record Are Burning Now: The Astonishing 2020 Wildfire Season in Context

Flames and heavy smoke approach on a western front of the Apple Fire, consuming brush and forest at a high rate of speed during an excessive heat warning on August 1, 2020 in Cherry Valley, California. The fire began shortly before 5 p.m. the previous evening, threatening a large number of homes overnight and forcing thousands to flee before exploding to 12,000 acres this afternoon, mostly climbing the steep wilderness slopes of the San Bernardino Mountains. (Photo by David McNew/Getty Images)

5 of California's 6 Largest Fires on Record Are Burning Now: The Astonishing 2020 Wildfire Season in Context

When you’re far from the fires, or when their smoke isn’t cloaking your neighborhood, it can be difficult to conceive of their scale. Here are nine graphics that put this year’s fires into context.

Editor's note: This post has been revised to reflect the most accurate data on fire acreage in the 1980s. The original relied on data from the NIFC for 1980-1983 and the updated version excludes this period, as the data are less reliable. The 1980s statistics now reflect data from MTBS and CalFire.

California is a state that burns. Like epic snowstorms in Tahoe, fog in San Francisco, and the dry heat of Palm Springs, wildfires are a natural feature of California's climate--and like all of those, wildfire is changing because of global warming. Rising temperatures are drying out soils, plants, and forests, which then act as fuel for increasingly large fires.

When you're far from the fires, or when their smoke isn't cloaking your neighborhood, it can be difficult to conceive of their scale. Here are nine graphics that put this year's fires into context.

Five record-breaking fires

Dozens of major wildfires are burning across the west, leaving what had been lives, homes, and forests in their wake.

California's largest fire on record

The largest of this year's fires, the August Complex Fire, has burned more than one million acres across seven counties in Northern California and is still growing.

Fires are burning areas that burned within the last few years

Many of the fires burning now are affecting fire-weary communities that have experienced extensive fires and evacuations since 2015. In some cases, this year's fires have burned right up to the edge of where previous fires left off, as if aiming for a devastating and cataclysmic completeness. In Napa and Lake Counties, this year's fires are burning in some of the very same places that burned just a few years ago.

Wildfire is part of California's climate

With the map below of all the wildfires on record in California, you can pick out, by eye, many of the state's geographic features: the arid and treeless Central Valley and Mojave Desert, which don't burn, the western slopes of the Sierras, the forests of Mendocino and northern counties, and the parts of the San Francisco Bay Area that are often covered in a thick, damp blanket of fog. The picture that emerges is one of a state where fire is common.

Within the perimeters of these fires lie the physical and emotional wreckage the flames have left behind. Outside the perimeters--in places like the Central Valley that look so neatly fire-free in this map-are the millions of Californians coping with dangerously smoky air year after year.

This year's fires are unprecedented

When you talk with people who have lived their entire lives in California, they are as shocked by what is happening as relative newcomers like me. Indeed, wildfires haven't always been like this. While decades of aggressive fire suppression have contributed to the problem, research shows that climate change is clearly playing a role in drying out vegetation and making fire more likely. As a result, wildfires are burning more land than they did in the past.

Wildfires in this single year alone have burned more of California's land than they did in the entire first decade of reliable recordkeeping (1984-1993). And nearly as much as the entire decade of the 1990s. And the year is not over.

Research suggests that continued global warming could increase the average area of California that burns by more than 75%. Because the state's forests are managed by the federal government, the state, and private landowners, we will need coordinated forest management efforts in addition to emissions reductions to minimize the scale of future fires.

A wildfire fingerprint

California is not the only state that has suffered through wildfires this year. If we take the fires that have burned across the western U.S. in 2020 and fit them together like a puzzle, they look something like this--fittingly, a lot like a human fingerprint:

This ignores many, many small fires and I'll be the first to admit that piecing the shapes of fires together is more art than science. It's less accurate than converting acres to squares and stacking them up neatly for comparisons. But the thought of representing these fires as little boxes felt too neat, too organized for something that forces us to contemplate the scars we're leaving on this Earth and those that nature is leaving on us.

The Bobcat Fire, burning just north of Pasadena, California, has left a large scar on the rugged landscape. (Source: NASA)

Over the past few weeks, winds have carried smoke from the fires out here across the country. The metallic yellow hue the smoke lends to the skies has given people from Wisconsin to Washington, D.C. a hazy hint of what it is like to live with the fires. The direct toll of this year's fires has prompted California to accelerate its efforts to combat the climate crisis. If fires left the same clear, heavy fingerprint on other states, would they do the same?

© 2023 Union of Concerned Scientists