Written by: James Nielsen

8,500 fires. Over 4 million acres burned. Nearly 10,000 structures destroyed. All in less than three months. California has never experienced a wildfire season this severe.

The state’s fire seasons have only lengthened and intensified over the past few decades—and even in the last couple years. Today, eight times more land is burned annually than was burnt in the 1970s. From 2001-2010, 7 million acres burned, and 12,428 structures were destroyed—those structures would occupy an area more than twice the size of downtown Los Angeles. From 2011 to the present, about 11 million acres have burned, and roughly 30,000 structures have been destroyed—more than five times the size of downtown L.A. A direct comparison of these two decades—2001-2010 and 2011-2020—shows a 57% increase in land burned. And even more shocking— 4.1 million acres burned in three months in 2020. This is equal 60% of the land area that burned during the nine years from 2001-2010.

September 8, 2020: A home burns in the Creek Fire in Fresno County, California.

This trend of fast-spreading severe wildfires has not surprised scientists, as model simulations and climate data over the past decade have pointed to current fire outcomes. According to insideclimatenews, climate change has already doubled the risk of extreme wildfire conditions in California, and will likely double them again in the next few decades. Even a decade ago, UC Berkeley scientists noted that the changing climate had caused the marine layer, the fog that keeps forests moist and the Bay Area cool, to decrease by ⅓. More recently, higher temperatures, higher winds, and lower humidity have made forests “prone to sustained fires if ignited”. Due to these consistently unfavorable conditions, the fire season has grown from about four months to almost a year.

But the frequency of wildfires is only a part of the problem; their intensity is increasing as well. In September, 900,000 acres of Oregon forest burned in only 72 hours. The annual average is 500,000. In the same month, in California, the North Complex fire consumed 200,000 acres in just 1 day. This significant increase in intensity is clear when comparing the worst fires in California on record: six of the top 20 most destructive wildfires have been in 2020. Two of those six are among the top 10 worst in state history.

A map of California’s fires as of September 15, 2020. Notice how the fires in yellow are all from 2020.

These extreme blazes are detrimental for the health of local ecosystems that have never been touched by fires before. For example, some of California’s coastal redwoods burned this year.

These huge trees are normally known for their ability to hold moisture. When ecosystems (such as these redwood forests) are burned, vegetation is killed and soil properties change. Rainwater is no longer able to effectively absorb into the ground, and instead builds up in the soil. This excess water creates large quantities of mud that are likely to slide downhill—and as they move, they pick up debris from the forest floor. As this debris moves, it grows larger and larger until even boulders can be picked up, causing landslides that can demolish towns.

After California fires in 2017, mudslides moved through Santa Barbara county at over 30 miles an hour, killing 17 people.

Although we may not be able to control the natural ignition of fires, such as the lightning strikes that started many of the west coast fires this year, we can reduce the chances of human-caused fires. Just a slight increase in our awareness about fire danger goes a long way. For example, instead of dropping a lit cigarette butt on the ground, one could place it in a closed container or in a glass of water—minimizing the chance of a potential wildfire. When starting campfires, there are a few rules to follow: only start them in official fire pits without dry vegetation nearby, don’t start campfires during high winds, and don’t leave the fire unattended overnight. Similar rules apply for burning yard waste or trash—never burn during high winds, burn only in a contained area, and don’t leave the fire unattended.

We can also take a bigger step by creating a “defensible space” near our own homes (if trees are nearby), which prevents existing fires from spreading. This area, extending to 100 feet beyond the house, is landscaped so that no trees or shrubs are closely packed, grass is cut short, and dead and dry plants are removed. Even better would be to only plant fire resistant plants, such as bush honeysuckles, currant, or hedging roses.

A diagram of the defensible space.

If we all take these steps, we can prevent the more immediate ignition and spread of wildfires. But in the long term, we must begin to change our habits in order to slow global warming—which causes drier forests that are more prone to ignition. To reduce our carbon footprint, we can “eat low on the food chain”, avoid buying “fast fashion”, drive less, and avoid unnecessary air travel. By eating more fruits, vegetables, beans, and grains, we lessen our consumption of animal products (meat and dairy), which account for over 14% of human-caused global greenhouse gas emissions. By avoiding cheap trendy clothing, we eliminate the need to dump the soon out of style items in the landfill which produces methane, a potent greenhouse gas. By driving less, we reduce carbon dioxide and nitrogen emissions. Similarly, flying less reduces carbon and nitrogen emissions.

These changes will help reduce the possibility of future heat waves, such as the California Public Utilities Commission’s prediction that in 2030, there is a 60% chance that three of the extreme heat events will last over six days. We could reduce the possibility of 2050 wildfires burning 77% more area in California then they do now. A unified effort to change the aforementioned habits will be necessary to save our landscapes from burning. It’s worth it.