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Wildfire

Wildfires are any unplanned or uncontrolled fire affecting natural, cultural, industrial and residential landscapes (adapted from FAO, 2010).

Wildfires are not a major cause of death, but they can be very destructive. Many wildfires are caused by human activities, either accidentally or as a consequence of carelessness, or arson. These fires often get out of control and spread over vast areas extending to tens or hundreds of thousands of hectares.

Even after the flames are gone, the health impacts of wildfires can linger for months—or years.

Research shows that wildfires can cause a large increase in gaseous air pollutants such as carbon monoxide, nitrogen dioxide, acetaldehyde and formaldehyde (Finlay et al., 2012). Wood smoke has high levels of particulate matter and toxins, Adverse health consequences can occur as a result of short- or long-term exposure. Respiratory morbidity predominates, but cardiovascular, opthalmic and psychiatric problems can also result (HPI).

Wildfires represent a hazard that is primarily influenced by humans and thus to a degree can be predicted, controlled and, in many cases, prevented. Wildfire occurence, characteristics and impacts are closely linked to other hazards: droughts, heat waves and extreme weather events can influence fire intensity and severity and thus the duration, size and controllability of wildfires. The effects of wildfires on vegetation cover and soil stability may create secondary hazards/subsidiary perils, such as post-fire landslides, mudslides, flash floods, erosion and siltation.

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Wildfire risks cascading impacts
The cascading effects of wildfires

    Risk factors

    • Increasing demand for agricultural lands for food and the necessity to use fire for land-use change.
    • The expansion of residential areas/infrastructures built near fire-prone vegetation - the Wildland Urban Interface (WUI).
    • Extended periods of drought and extreme heat.
    • Wildfires cause more land degradation (soil erosion, loss of land productivity) and as a consequence create more flooding and landslides.
Costs of wildfires
The invisible costs of wildfires

Vulnerable areas

  • Agricultural and pasture lands in which fire is used for controlling weeds, bush encroachments, and for land clearing.
  • Fire-prone natural forest, bush land and grassland ecosystems with high occurrence of natural fires in the subtropics or northern latitudes.
  • Agricultural and forest plantations.
  • Residential areas or scattered houses/infrastructures nearest to fire-prone vegetation.
  • Residential areas or individual structures made of easily flammable materials.
  • Abandoned rural villages and human settlements with no one to manage, prevent or respond to wildfires.
How to reduce wildfire risk

Risk reduction measures

  • Limit development in high bushfire risk areas.
  • Clear the vegetation surrounding homes and other structures.
  • Build fire lanes or breaks between homes and any forested or bush land areas, if a natural firebreak does not exist.
  • Plant vegetation of low flammability.
  • Use fire-resistant building materials.
  • Use traditional and advanced methods of prescribed burning for sustainable agriculture and flora and fauna management.
  • Enact legislation and regulation at the appropriate jurisdictional levels.
  • Conduct community-based fire risk minimization activities during all stages of fire management.
  • Provide community alerts through fire danger rating systems.
  • Educate the community and raise public awareness about the risks of wildfires.
  • Develop firefighting capacities and public safety.

Explore 5 smart and proven ways to reduce wildfire risk before fires start.

Latest Wildfire additions in the Knowledge Base

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Extreme weather resilience: why it matters and how we’re building it thumbnail
Documents and publications

This paper examines why extreme weather resilience is becoming a core priority for infrastructure investors and how it should be built into investment decisions.

Actis
Update

A 2019 Australian bushfire provided a rare opportunity to scientists by creating an effect analogous to what could be achieved through the geoengineering technique known as marine cloud brightening.

University of California, San Diego
Sahara desert in Algeria
Update

In the summer of 2021, the hills of northeastern Algeria disappeared behind walls of smoke. Wildfires swept through Béjaïa, El Tarf, and Tizi Ouzou with a speed and ferocity that overwhelmed communities and firefighters alike.

World Bank, the
Update

An Oregon State University study found that mechanically ventilated spaces were better than window AC and mini-splits at lowering indoor particulate matter concentrations.

Facilities Dive
The perils of risk communication in a context of uncertainty: The  long dispute over contamination after the Grenfell Tower fire thumbnail
Documents and publications

This study examines post-disaster risk communication after the Grenfell Tower fire, arguing that acknowledging uncertainty, enabling inclusive risk assessment and applying precaution can help rebuild trust between authorities and affected communities.

International Journal of Disaster Risk Reduction (Elsevier)
Gloved hands connecting the power cable to the extension reel socket, with a yellow cable wound around the green drum during outdoor electrical setup.
Update

A severe winter snow drought has left snowpack levels far below normal across the American West in 2026.

Conversation Media Group, the
Research briefs

Mendocino and Monterey could become increasingly favorable for premium vintages under shifting climate, while Napa and Sonoma may face increased pressure in grape cultivation.

Frontiers in Climate
Olive trees burn during a wildfire in Greece
Research briefs

In some parts of Southern Europe, more than half of the land has burned at least once in the last two decades.

Centro Euro-Mediterraneo sui Cambiamenti Climatici (CMCC)
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