California: Let It Burn?

As we all know, social media is both a blessing and a curse. One of the negatives of social media has been the propagation of misinformation and catchy sayings or infographics that just don’t hold any truth.

The biggest one of these has been regarding the wild fires of 2020, specifically of those in California and the Western United States. I’ve seen tweets comparing 2019 wildfire statistics to those of 2020, and posts like “I don’t need a time machine to see climate change, all I have to do is look outside my window,” set to scenes of red smoky skies. As you can imagine, these and other similar posts have gone viral, but they are problematic. 

They are problematic for the same reason: because of the time needed to actually evaluate changes in climate. The tweet of 2019 vs 2020 fire stats is really portraying year to year variability which is NOT synonymous with climate change. Secondly, “looking out your window” only shows a current snapshot of the climate, and in fact to analyze CHANGE you need something else to compare it to, not a singular moment in time. Wildfires are a naturally occurring type of disturbance on the landscape, and depending on local and regional climates, the frequency and intensity can vary drastically.

Part 1) First let’s evaluate climate variability vs climate change

Climate variability is the short term changes in weather patterns, such as month to month, year to year, or even the course of a few years, with most notable examples being El Nino and La Nina cycles. Generally speaking, the minimum time needed to evaluate climate change is at least a decade, if not several. 

So what does climate change science say about California?

According to the US Environmental Protection Agency (EPA), southern California has warmed approximately 3 degrees Fahrenheit in the last century¹. This increasing temperature is melting snowpacks in the mountains, and combined with increased evaporation rates (worsened by manmade impoundments), is reducing freshwater availability. With decreasing water availability and increasing temperatures, fire conditions become exacerbated. According to the EPA, on average, 4 percent of the land in California has burned per decade since 1984.

Part 2) History of Wildfire Management in the United States

Understanding fire ecology and the role of fire as a natural disturbance to the landscape is a key component in evaluating the effects of climate change on wildfires. 

Total Fire Suppression

The United States Forest Service (USFS) was founded in 1905, with federal forestry management dating back to 1876. Since its origin, the USFS fire management policy was total fire suppression, especially after wildfires struck the states of Montana, Idaho, and Washington, in 1910, burning 3 million acres in a mere two dates. This total fire suppression management lasted approximately 100 years².  While the USFS has changed their views on wildfires with new advances in knowledge and technology, and even performing prescribed burns where and when it’s safe, the impacts of wildfire suppression are still felt today.

Fire Frequency and Intensity

Fires are natural disturbances in the landscape but depending on where you live, the frequency and intensity of wildfires will vary. For example, I live in New England, and much of the northeastern United States consists of a temperate forest biome, receiving moderate rainfall. Because of our cooler, wetter climate in the northeast, fires are less frequent, but historically more intense. Few plants in the northeast are fire resistant, and even fewer are fire dependent. The western United States has a more arid climate and generally experiences hotter temperatures. Fires are much more common, and as a result, fuel loads are less and fires burn with a lower intensity. Because fires play a more consistent role in the landscape out west, local plant and animal communities have evolved to tolerate and depend on fire. Essentially lower frequency-higher intensity and vice versa, higher frequency-lower intensity.

An explosive combination

The combination of total fire suppression in a high frequency fire dependent landscape in the western US resulted in accumulation of fuel loads (dead and living vegetation). This accumulation of fuel increases the intensity of the fire³. With millions of acres to manage and 100 years of total fire suppression, we are still playing catch-up, made even harder with climate change exacerbating conditions for wildfire.

Part 3) Human Encroachment

The last component of this evaluation between wildfires and climate change is the human element. We all know that the recent El Dorado fire in California was caused by a gender reveal smoke bomb malfunction. Between 1940 and 2000, 10 million housing units were constructed in California alone⁴. With human development and activity expanding into these rural or wild spaces, there has been a corresponding increase in human caused wildfires. Not only has human activity extended fire seasons, it has also increased the total area burned by wildfire. An analysis of 1.5 million government wildfire records from 1992 to 2012 found that human activity (aka human caused fires) accounted for 84% of all records, and 44% of total area burned. Human caused fires were most prominent in the eastern United States and central and southern California. While lightning ignited fires have also been on the rise, they only dominated in 8% of area burned, and primarily occur in the intermountain west and Florida⁵.

In Summary

Ultimately, yes, climate change is worsening conditions for wildfires across the world, but this alone does not show the full complexity of what’s happening in the United States. A century of fire suppression with simultaneous increases in human population and density has resulted in not only more fires, but more intense fires, which is now being compounded by the effects of human accelerated climate change.

What can we do in the immediate and interim future

Now that we know the many factors which contribute to the worsening wildfire conditions in the United States, we need to take a multifaceted approach to achieve appropriate solutions.

Reduce Urban and Suburban Sprawl

With human activity directly contributing to increase in wildfire ignition and duration of the season, reducing spread of human development into rural areas and more fire prone habitats is a key strategy towards limiting human caused wildfire. Additionally, human sprawl can also contribute to climate change via longer commutes, need for more facilities like schools, hospitals, etc, and conversion of habitat from potential carbon sinks to carbon sources. Local zoning ordinances, downtown revitalization projects, and conservation easements are a few ways to help reduce urban and suburban sprawl. 

Protected Contiguous Habitat 

Even though plant and animal communities in higher frequency fire regions have adapted to fires, this depends on the availability of other habitat to occupy while the burned area regenerates. It’s not uncommon to see wildlife in human developed areas during or after a fire as they may be seeking refuge or food. Providing contiguous habitat blocks and wildlife corridors allows for wildlife to disperse into new habitats after a fire.

Sustainability Initiatives, Practices, and Legislation

Science has shown that climate change is worsening conditions for wildfires not just in the United States but across the world, with record setting wildfires occurring in Amazon rainforest in 2019 and Australia in early 2020. Not only do we as individuals need to adopt more sustainable practices into our everyday lives, but corporations need to push sustainability initiatives and create more sustainable products. Part of this push can come from the purchasing power of consumers, but in large part we also need action from our government to create and enforce environmental regulations. Imagine where we would be today without the National Environmental Policy Act established in 1970, the Clean Air Act of 1970, the Clean Water Act of 1972, the Endangered Species Act of 1973, and several other key pieces of environmental legislation that have followed. Do you think corporations were happy then about this legislation that finally held them accountable for decades of industrial pollution? Of course not, and what I’m sure was declared as “impossible” for them to survive financially is now the standard. Corporations will always push back against things that cost them the bottom line, but continuing to put the environment at the bottom and continually increasing profit margins at the top is irresponsible and unjust. 

Thank you for reading this brief introduction into wildfire ecology and management. For more information on wildfire science, view the cited sources below.

1. US Environmental Protection Agency. “What Climate Change Means for California.” August 2016, https://www.epa.gov/sites/production/files/2016-09/documents/climate-change-ca.pdf  Accessed 04 October 2020.
2. Smith, Dianne M. Sustainability and Wildland Fire: The Origins of Forest Service Wildland Fire Research. United States Department of Agriculture – United States Forest Service, 2017. https://www.fs.usda.gov/sites/default/files/fs_media/fs_document/sustainability-wildlandfire-508.pdf Accessed 04 October 2020.
3. Steel, Zachory L., et al. “The fire frequency‐severity relationship and the legacy of fire suppression in California forests.” Ecosphere, vol. 6, no. 1, 2015, pp. 1-23. https://esajournals.onlinelibrary.wiley.com/doi/10.1890/ES14-00224.1#:~:text=As%20a%20disturbance%2C%20fire%20is,White%201985%2C%20Turner%20et%20al. Accessed 04 October 2020.
4. Mann, Michael L., et al. “Modeling residential development in California from 2000 to 2050: Integrating wildfire risk, wildland and agricultural encroachment.” Land Use Policy, vol. 41, 2013 revised 2014, pp. 438-452. https://www.sciencedirect.com/science/article/pii/S0264837714001409. Accessed 04 October 2020.
5. Balch, Jennifer K., et al. “Human-started wildfires expand the fire niche across the United States.” PNAS: Proceedings of the National Academy of Sciences of the United States of America, vol. 114, no. 11, 2017, pp. 2946-2951, https://www.pnas.org/content/114/11/2946.full. Accessed 06 October 2020.