Wildfire Hazards in California

California has been on fire since August.

The interactive map embedded on this page can serve as a tool to learn more about fire hazard in the state.

Fire Ecology

California is predominately made up of chaparral and coniferous ecosystems. These particular systems have evolved to be reliant on fire. The landscape, plants, and trees depend on low-grade "goldilocks fires" in order to stay healthy. Fire can help soil retain water, keep brushy vegetation down, and aid in managing the overpopulation of destructive species (e.g. the pine bark beetle) – which encourages the growth of native plants. Additionally, many tree species require fire to reproduce.

Fire Suppression

Fire suppression has been a common practice throughout the West for over a century, in part due to the misconception that wildfires are always harmful to nature, coupled with a lack of understanding of California's ecosytems. But these practices have seen a drastic spike due to an increase in population in the most severe fire-prone areas.

Fire suppression contributes to a decrease in forest health and an increase of overgrown vegetation and dead matter that double as fuel. The overgrown undergrowth creates a "fire ladder" up the canopy, which allows ground and surface fires to quickly transition into crown fires. This means that when fires do escape suppression, they are more destructive. These factors lead to fires that are more frequent, last longer, spread further, and burn more intensely – killing more trees and wildlife, burning down more homes and communities, and releasing more carbon dioxide into the atmosphere (further contributing to climate change).

Climate Change

The effects of fire suppression are further excacerbated by climate change. In the past decade, California has seen more extreme weather – warmer temperatures, longer drought periods, stronger winds, more intense lighting storms. These are all optimal conditions for the development of wildfires. This creates a positive feedback loop: Wildfires contribute to climate change and this then encourages bigger wildfires, which further contributes to climate change and so forth.

2020 Fire Season

California just set a record for land scorched by wildfires. This year alone, over 2.1 million acres have burnt across the state. The fire season lasts well into October and November, meaning this number will likely get much higher. Currently, there are over 20 active wildfires, so far mainly concentrated in Nothern California. The LNU, SCU and CZU Lightning Complex fires were all sparked by clusters of lightning from a tropical thunderstorm in mid-August. Combined, these fires have destroyed thousands of structures and severely damaged many natural areas, including Big Basin Redwoods State Park – California's oldest state park. In Southen California, record high temperatures provide ideal conditions for fires in the nearby mountains. Currently, the Bobcat Fire – a brushfire in Los Angeles County – has burned over 1,800 acres of the Angeles National Forest.

How an ovegrown forest due to suppression burns compared to a healthy and well-managed forest. (The Nature Conservancy)

Map showing the general area of some of the most severe fires currently burning in Nothern California. (KTVU FOX 2)

Fire Hazard Zones

The map below shows fire hazard areas classified into moderate, high, and very high hazard. Most of the state falls under one of these categories, meaning that California is very prone to fire. This layer is intended to show whether major cities and other populated areas fall within a hazard zone, and if so how severe is the danger. By looking at the map with the satellite data base layer, the most dangerous zones are heavily forested/natural areas. However, because many major cities are within or right outside these boundaries, they are also at risk.

Responsible Firefighting Authority

Given the size and population of the state, no one single agency can be responsible for all fires. Instead, firefighting responsibilities are assigned to different authorities. The California Department of Forestry and Fire Protection oversees State Responsibility Areas. SRAs are found in 56 of the 58 counties and total over 31 million acres. The rest of firefighting authority is overseen by either the federal government or local government entities such as cities, counties, and districts. This layer is intended to show what authority oversees which areas. It is important for residents near hazard zones to know this information so they know who to contact and where to receive updates and information in case of a fire.

Public Schools

Public schools are frequently used as evacuation centers in major disaster events – including fires. The public schools layer is intended to show the proximity and quantity of possible evacuation centers in areas of high fire hazard.

Above is a slideshow of a map of California. Each slide highlights a different area and shows different layers. The first two show the hazard zones and firefighting responsibility areas respectively for the entire state. Here you can zoom in and explore the relationship between land features and hazard zones – what type of areas tend to be more fire-prone? Are major cities affected? Right-clicking on these zones opens up a pop-up with information about the hazard zone and the responsible authority. The legend button on the top right corner also provides information about what each color represent.

The next two maps show this same information but zoomed in on LA county. At this scale, you can see county and city borders. Right-clicking on a city will open up a pop-up box with population and density information. This information can be helpful to contexualize how catastrophic a fire can be if it reaches urban areas.

The fifth slide shows public schools near the Bobtail Fire area. Unlike the other maps, this map uses a nagitvation-style basemap rather than a satellite image. This base shows major roads and street names, useful if trying to find the nearest evacuation center and how to get there. A satellite basemap is useful if trying to see land features, but is not very useful for nagivation purposes. Right-clicking on each school opens up a pop-up with more information about the school.

The last slide is zoomed to show Westwood. UCLA lies just outside fire hazard zones, meaning it is within the realm of possibility for an intense wildfire to reach the area – in fact, there has been at least one fire per year near campus for the past few years. This map could help students explore the areas near campus, and helped them be prepared if need be.

Note that not all layers can be seen at every scale. City labels and schools will only appear when zoomed in close enough.

*For sources, click on sources tab

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