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Jennifer Balch recently published in  about how the speed of fire spreading is the key factor in determining the damage they cause, with the article making the cover of Science. CIRES released a  on this with more information. Below are some excerpts from this article.

“Some of the most deadly and destructive wildfires in US history have occurred in recent years, with most having the common characteristic of extremely rapid growth. The 2018 Camp Fire in California burned >21,000 ha the day it started, killing 85 people and destroying >16,000 homes. The 2021 Marshall Fire, the most destructive wildfire in Colorado history, was driven by winds >100 mph; it traveled 3 miles within the hour it started and burned >1000 homes. The 2023 Lahaina Fire in Hawaii killed 101 people and destroyed >2200 structures when a small brush fire escaped containment and burned through the town to the shore in 2 hours. The modern era of megafires is often defined based on wildfire size (1), but it should be defined based on how fast fires grow and their consequent societal impacts. Speed fundamentally dictates the deadly and destructive impact of megafires, rendering the prevailing paradigm that defines them by size inadequate. Although big fires change air quality, ecosystems, and carbon dynamics (2), fire speed matters more for infrastructure risk and evacuation planning (3). …

… Herein, we delineate a new class of the fastest growing and most destructive fires, or fast fires. This class is akin to “mega-fires” but is defined based on a maximum daily growth rate of >1620 ha/day, where we document most of the structures destroyed (78%) and suppression costs (61%) despite these fires only accounting for 2.7% of all wildfire events (2001-2020). A major advance is that this class of fast fires is defined by both the physical behavior and societal impact, representing coupled social-environmental extremes (48). … Current national fire risk models and planning efforts tend to focus on fire probability, intensity, or area burned (50) rather than on fire speed and consequent settlement exposure or potential damage. Fast fires matter for life safety and structure impacts; large fires matter more for ecosystems and they generate substantial smoke. The speed of a fire determines (i) whether firefighters are more focused on evacuation than home protection (17) and (ii) how effectively they can extinguish burning firebrands and new ignitions on structures before the home becomes fully involved (38, 39). …

… We also document that fires are growing significantly faster across nearly half of the CONUS land area and 2.5 times faster across the Western US in just 20 years. Increasing speed will challenge emergency response, evacuation plans, and community preparedness (52). Incident command reports indicate that at least 925 emergency evacuation orders affected >1.5 million households between 2001 and 2020 (44), and approximately half of these were within 1 km of a fast fire (Fig. 4). Wildfire-related emergency evacuation success will be influenced by the density of human settlements, road access (53), and efficient use of early warning systems and information delivery to affected communities (54), all of which will be compromised by faster-moving fires. With maximum daily growth occurring within the first 5 days after ignition for 83% of all events (fig. S2B), we also need to focus on proactive measures that slow fires down or promote fire resilience of the built environment. …”