Click the link to watch the video on YouTube:
Jan 10, 2025
Key takeaways:
● Researchers used NASA satellite data to analyze the growth rates of over 60,000 fires in the contiguous U.S. from 2001-2020
● Results show fast-growing fires caused 88 percent of fire-related damages in the U.S. between 2001-2020 despite representing less than 3 percent of fires on record during that time.
Fast-growing fires were relatively rare in the United States between 2001-2020, yet they were responsible for nearly 90 percent of fire-related damages, according to a new study published in Science and featured in a new episode of PBS Weathered. These wind events with fire in them send embers far ahead of advancing flames, jump over rivers and highways and rapidly ignite homes. These fast fires overwhelm suppression response. The groundbreaking research relied on new remote sensing tools and shows these fires are getting faster in the Western U.S., increasing the risk for millions of people, and highlighting the actions we need to take before fire comes. “We hear a lot about megafires because of their size, but if we want to protect our homes and communities, we really need to appreciate and prepare for how fast fires move,” said Jennifer Balch, fire scientist and the lead author of the study. “Speed matters not only for understanding how fires evolve but also for keeping people safe.” NASA worked with Navteca to create scientifically accurate, time-based animations of several fast fires, including:
- The East Troublesome fire, which destroyed hundreds of homes in and around Grand Lake in the Colorado Rockies, raced over 18 miles in a single day and jumped the barren Continental Divide,
- The 2020 Labor Day fires in Oregon and Washington, where a statewide 2,000 foot deep river of wind flowed down from the interior of North America, knocking down power lines and fanning existing fires into rapidly growing fires that burned communities across Oregon,
- The Marshall Fire, which destroyed more than 1,000 homes in Boulder County, Colorado, in December 2021. The fire burned less than 6,100 acres but grew quickly due to a combination of dry conditions and high winds. Less than an hour after the fire was reported, it had spread to a town 3 miles away, forcing tens of thousands of people to evacuate, and
- The Lahaina Fire which burned 2,170 acres, destroyed 2,285 structures (mostly residential) and killed 98 people. The fire was driven by sustained winds of 30 mph with gusts doubling that.
Fast fires grew more than 4,000 acres (more than 6 square miles) in a single day. The analysis revealed a staggering 250 percent increase in the average maximum growth rate of the fastest fires over the last two decades in the Western U.S. U.S. Fire Administrator Dr. Lori Moore-Merrell reflected: “This research helps us focus our attention on what causes the most loss and what we can do to prepare before fire comes to make us savable.” Fast fires accounted for 88 percent of the homes destroyed between 2001 and 2020 despite only representing 2.7 percent of fires in the record. Fires that damaged or destroyed more than 100 structures exhibited peak fire growth rates of more than 21,000 acres (more than 32 square miles) in a single day. The work also highlights a critical risk assessment gap. At the national level, wildfire risk models include parameters for area burned, intensity, severity, and probability of occurrence, but they do not incorporate growth rate or other measures of fire speed. Government agencies and insurance companies that use these models are therefore missing vital information about how fires spread, which homeowners could use to better protect themselves and their communities. “When it comes to safeguarding infrastructure and orchestrating efficient evacuations, our satellites and earth observations are telling us that the speed of a fire’s growth is a dominant factor in home and community loss.” Dr. Falkowski, Director of NASA’s wildland fire program said.
