Photo 97309546 © Blackkango |
A wildfire over the Grizzly Peak in the Oakland area in San Francisco Bay. The fire caused the evacuation of the University of California, Berkeley.

Modeling Wildfire Risk in 2020 and Beyond

Aug. 26, 2020
Scientifically supported, peer reviewed solutions for risk modeling can offer powerful insights into wildfire mitigation, monitoring, reporting, and response.

It is only the beginning of the 2020 wildfire season and already there have been 20,351 U.S. wildfires between Jan. 1 and June 12. Compare this to 16,630 fires during the same period in 2019, according to the National Interagency Fire Center (NIFC).

As many as 90% of the wildfires in the United States are caused by people, according to the U.S. Department of the Interior. Some are caused by unattended campfires, burning of debris, downed power lines, negligent discarding of cigarettes, and intentional arson.

In many cases, increasing wind-driven events cause fires to spread over greater distances, creating exponential expansion of a wildfire. Fire spreads from hillsides to various points in the valleys, creating spot fires with no relationship to the main wildfire body. Examples of late season fires being compounded by extreme winds include several Southern California fires in 2019.

When One Disaster Follows Another

Across the United States and Canada, the scale of forest fires has increased to such a degree that the fires themselves are now contributing to the rise in greenhouse gas emissions. And some fires are even creating their own weather systems, making winds more erratic and conditions too dangerous for firefighters to protect people and properties. These fires are often called megafires and they are becoming more common. Some bushfires in Australia created powerful pyrocumulus clouds that led to smoke-infused thunderstorms. The lightning from these storms threatened new fires, which sometimes developed into fire tornadoes.

Warmer temperatures do more than just dry out the land. They also heat up the atmosphere, where clouds hold onto more moisture for longer periods of time, causing severe drought and fire. This is often followed by crushing rains that can’t be absorbed by severely dry lands. When floods and mudslides destroy property where fires blazed nearby, a cycle of what scientists call “compound extremes” — one climate disaster intensifying the next — makes recovery more difficult.

Evacuations and Blackouts Made 2019 Unique

While the 2019 wildfire season in the United States was not as active as 2018, disruption was still significant, leading to the evacuation of over 200,000 people and the declaration of a state of emergency in California.

One of the most notable aspects of the 2019 California wildfire season was the introduction of scheduled intentional power outages by utility companies when fire conditions were forecast. This was meant to minimize or eliminate ignition risk from downed power lines. These preemptive power shutoffs occurred in approximately 30 counties in California for approximately 23 days total, by Pacific Gas and Electric Company (PG&E), Southern California Edison (SCE), and San Diego Gas & Electric (SDG&E). The shutoffs initially affected around 800,000 customers or about two million people. Stanford University’s Michael Wara, an expert on electricity policy in California, estimated the total costs of the blackouts to be somewhere between US$1.8 billion and US$2.6 billion.

The shutdowns drew widespread criticism from residents as well as government officials. Many businesses and residents complained of either being misinformed or not informed when shutdowns would occur. The state of California developed programs to protect utility companies and consumers in the advent of future wildfire events. The state legislature passed a bill that created a US$21 billion state-run insurance pool to act as a cushion for utility companies against future wildfire claims.

Wildfire Modeling

Wildfires are a rapidly growing challenge — and businesses need better tools to manage this risk. Predicting wildfire-related risk requires understanding more than just fire history, frequency, and severity. Using solutions that are scientifically supported and peer reviewed can provide powerful insights into wildfire mitigation, monitoring, reporting, and response.

Reinsurance and risk modeling experts have begun using terms such as “megafires” and “the new abnormal”, as they have identified several contributing trends of interest:

  • Increase in property development in and adjacent to Wildland Urban Interface (WUI) areas.
  • Increase in fuel loads on the ground, including dead standing trees because of drought and insect infestation, along with a decrease in fuel moisture content as a result of prolonged arid conditions.
  • Increase in weather volatility from year to year, including several years of drought interspersed with a few very wet winters, as well as longer dry seasons extending later in the year, when intense seasonal wind patterns are most likely to spread fires.
  • Changes in fire behavior, with rapid expansion becoming more explosive in terms of quickness and distance, because of a confluence of extreme conditions including high temperatures, low humidity, strong winds, high fuel loads (vegetation and structures), and steep, hilly terrain. Fires have consumed up to 70,000 acres a day and traveled over 15 miles in a few hours, with embers blown across multilane highways into developed areas within city limits.
  • Multiple fires have erupted at the same time and often in close proximity, stretching the availability of fire-fighting resources and their capability for aerial drops of retardants because of massive smoke plumes that reduce visibility.

COVID-19 Challenges

The 2020 fire season presents new challenges related to COVID-19. The pandemic has raised the stakes at the worst possible time, forest managers say, and is forcing firefighters, officials, and communities to rethink how they combat blazes. One such consideration is firefighters moving from blaze to blaze in camping groups while not on the frontlines. This previous practice is now considered a dangerous incubator for COVID-19. Also, the combination of smoke inhalation and the novel coronavirus complications greatly expand respiratory risks for first responders.

The continued spread of the coronavirus, as well as the economic paralysis that has accompanied health restrictions, has impacted every aspect of wildland firefighting. With fires beginning earlier in the spring and persisting later into the fall, communities may have to contend with the dual risk of COVID-19 and wildfire for several months.

Voice your opinion!

To join the conversation, and become an exclusive member of T&D World, create an account today!