US wildfires

Wildfire blowups, fire whirls, towering thunderstorms: When fires get large and hot enough, they can actually create their own weather. In these extreme fire situations, firefighters’ ordinary methods to directly control the fire don’t work, and wildfires burn out of control. Firefighters have seen many of these risks in the enormous Park Fire burning near Chico, California, and other wildfires in summer 2024. But how can a fire create weather? Satellite images show how the Park Fire near Chico, Calif., created intense pyrocumulonimbus plumes, visible in white, in July 2024. CSU/CIRA and NOAA I’m an atmospheric scientist who uses data collected by satellites in weather prediction models to better anticipate extreme fire weather phenomena. Satellite data shows fire-produced thunderstorms are much more common than anyone realized just a few years ago. Here’s what’s happ...

Extreme heat has already made 2024 a busy wildfire year. More acres had burned by mid-July than in all of 2023, and several communities had lost homes to wildfires. As fire season intensifies across the West, there are steps homeowners can take to make their homes less vulnerable to burning and increase the likelihood that firefighters can protect their property in the event of a wildfire. We research wildfire risk to homes and communities. Here’s what decades of research suggest homeowners in high-fire-risk areas can do to protect their properties. This house near Cle Elum, Wash., survived a 2012 wildfire because of the defensible space around the structure, including a lack of trees and brush close to the house, according to state officials. AP Photo/Elaine Thompson Small improvements make big differences A structure’s flammability depends on both the materials that were used to build...

When wildfires rage, the immediate threat is obvious – but smoke from the fires actually kills far more people than the flames. As fires become more frequent, that smoke is leading to a public health crisis. In a new study published in the journal Science Advances, we found that wildfire smoke likely contributed to more than 52,000 premature deaths across California alone from 2008 to 2018, with an economic impact from the deaths of more than US$430 billion. Previous studies have examined the short-term health risks from wildfire smoke, but few have assessed how exposure to wildfire smoke over years adds up to shorten human lives. Smoke from far-off wildfires turns the skies orange over San Francisco in 2020. Running in wildfire smoke carries harmful particles deep into a person’s lungs. AP Photo/Tony Avelar Wildfire risk and severity have grown as the climate has changed and as more...

Wildfire blowups, fire whirls, towering thunderstorms: When fires get large and hot enough, they can actually create their own weather. In these extreme fire situations, firefighters’ ordinary methods to directly control the fire don’t work, and wildfires burn out of control. But how can a fire create weather? Satellite images show how the Park Fire near Chico, Calif., created intense pyrocumulonimbus plumes, visible in white, in July 2024. CSU/CIRA and NOAA I’m an atmospheric scientist who uses data collected by satellites in weather prediction models to better anticipate extreme fire weather phenomena. Satellite data shows fire-produced thunderstorms are much more common than anyone realized just a few years ago. Here’s what’s happening. The wildfire and weather connections Imagine a wildland landscape with dry grasses, brush and trees. A spark lands, perhaps from...

In the U.S., wildland firefighters are able to stop about 98% of all wildfires before the fires have burned even 100 acres. That may seem comforting, but decades of quickly suppressing fires has had unintended consequences. Fires are a natural part of many landscapes globally. When forests aren’t allowed to burn, they become more dense, and dead branches, leaves and other biomass accumulate, leaving more fuel for the next fire. This buildup leads to more extreme fires that are even harder to put out. That’s why land managers set controlled burns and thin forests to clear out the undergrowth. However, fuel accumulation isn’t the only consequence of fire suppression. Fire suppression also disproportionately reduces certain types of fire. In a new study, my colleagues and I show how this effect, known as the suppression bias, compounds the impacts of fuel accumulation and climate change. What happened to all the low-intensity fires? Most wildfires are low-inten...