Civilian Use of Fire Weather Information and Technology During Extreme Fire Events: Findings from Case Studies of the 2022 Mill and 2021 Caldor Fires in California.

Preserving human health and safety during a wildfire event is a foremost priority for emergency mangers and fire professionals in fire-prone regions of the world. While most fire and emergency response organizations focus on promoting civilian evacuations as early as possible to maximize public safety, existing wildfire social science and disaster decision-making literature demonstrates that civilian evacuation decisions are influenced by a variety of factors that do not always end in a decision to evacuate early, or at all. In recent years, the incidence of extreme wildfire events that deviate from the norms of what both professionals and locals expect of wildfires in their area has increased. The case studies presented here utilize over 100 semi-structured interviews and social network analyses to explore how changing fire behavior and weather have influenced evacuee and professional decision-making on two wildfires, the 2022 Mill Fire in Weed, CA, USA where a fast-moving wildfire that started at a lumber mill burned 3,935 acres (1,592 hectares), destroyed 118 structures, and claimed two lives in a rural landscape with a legacy of livelihoods tied to logging over a span of three days, and the 2021 Caldor Fire that burned 221,835 acres and destroyed more than 1,000 structures in the Sierra Mountains and burned for several weeks. Both fires exhibited elements of extreme fire behavior and weather that influenced fire, emergency, and civilian decision-making. We found that distinct populations impacted by the same wildfire engaged with and valued different information sources depending on their proximity to the wildfire’s ignition point and the amount of time they had to engage in information mining. On the Mill Fire, communities nearest the ignition point had no warning, often responding to environmental cues like smoke or seeing the fire or being notified by neighbors or yells. Emergency alerts could not activate until emergency professionals were able to engage their emergency notification systems, which were outpaced by the wildfire’s speed for the closest communities. Consequently, community members nearest the fire’s origin tended to have smaller information networks as compared to communities farther away that had more time to become notified and mine for data to inform their evacuation choices. Civilian-run information sources, such as Watch Duty, were often utilized on the Mill Fire because they rapidly outpaced information delivery from official sources, in part due to agency-mandated verification processes. However, Watch Duty was lesser utilized on the Caldor Fire due it being newer. Interviewees in both case studies valued official information from CalFire, the US Forest Service, and emergency services and preferred to get their information from those avenues, but largely reported lower scores on some measures due to the temporal resolution limitations official sources of information grapple with (e.g., needing to verify and get administrative approval to share information officially with the public). Due to this bureaucratic hurdle, most information shared by agencies was considered outdated by the time it was shared and not useful for making decisions about evacuations. However, Code Red Alerts were highly valued for triggering evacuations and making participants aware of wildfire events in their area. Despite the advantages of more frequent information, some participants noted concerns around the circulation of inaccurate or malevolent information on unofficial forums, especially in community social media groups such as Facebook or Nextdoor. Finally, we found that the frequency of resident information-seeking behaviors increased and peaked after the initial fire danger passed, with many residents engaging with information nodes outside of their informal network to gather information on the status of their home, reasons for sustained evacuation orders, and re-population. Overall, this talk presents a comparison of how civilians utilized fire-related information during two wildfire events and provides suggestions on how managers and scientists can better engage with and inform civilian evacuation decisions under a changing climate.