By JEN HOLLIS AND STUART MATHEWS

To most Australians, fire danger forecasting is embedded within our cultural identity and history. It’s as Australian as kangaroos, the Holden Ute and the Sydney Opera House.

For the last six decades Australians have relied heavily on the pioneering work of Alan McArthur who developed the Forest Fire Danger Index and Grassland Fire Danger Index. The system has served Australians well and with only minor adaptations to meet local needs, it remains largely unchanged. The most significant adjustment came after the 2009 Black Saturday fires in the state of Victoria which, in one afternoon, burned through more than 450,000 hectares and resulted in the devastating loss of 173 lives.

Following a Royal Commission investigation into the fires, it was recognised that McArthur’s system was being applied well beyond the original design. As a result, categories were added, including one at the top end of the fire danger scale reflecting conditions beyond the existing maximum of 100. Importantly, it was also recognised that there was a need to incorporate new science and technological developments (for example, remote sensing, landscape mapping, higher computational capability) into calculating and interpreting fire danger.

International Association of Wildfire. 2022.

By N. Bénichou, M. Adelzadeh, J. Singh, I. Gomaa, N. Elsagan, M. Kinateder, C. Ma, A. Gaur, A. Bwalya, and M. Sultan

Fires in the wildland-urban interface (WUI) have become a global issue, with disasters taking place all over the world recently. The drivers of increasing WUI fire risk—increasing population and expansion of urban areas into wildlands, and climate change—are global-scale phenomena. In the coming decades, WUI fire risk is expected to increase both in regions with a long history of fires and in regions that have had been less affected over past decades. WUI fires can cause the ignition of many structures through the spread of flames and radiant heat and the deposition of burning embers over a short period of time. This can overwhelm protection capabilities, lead to large evacuations, and cause disasters with the potential for the total loss of hundreds of structures in a few hours.

As discussed in Chapter 1 of this Guide, over the last decade, an average of 5 533 wildfires have occurred each year in Canada, involving 2.9 million hectares of wildland area. The number of evacuations caused by wildfires increased by about 1.5 evacuations per year between 1980 and 2014, with more than 20 evacuations per year after 2010. The substantial negative impacts of WUI fires were illustrated by the Okanagan Mountain Park Fire, which affected Kelowna in 2003; the Flat Top Complex Wildfire, which destroyed significant parts of Slave Lake in 2011; and the Horse River Fire, which immensely affected Fort McMurray in 2016 and was the most costly insured loss event in Canadian history. These disasters resulted in a loss of over 2 400 structures and roughly 3 400 dwelling units. Total insured losses from these wildland fire disasters and the 2017 wildland fire catastrophic events in British Columbia are currently estimated to be $4.8 billion. Despite all efforts, wildfires pose a significant challenge to the residential population, to mitigation efforts, and to existing infrastructure when located in a WUI setting. Wildfires are likely to become more severe and frequent as a result of climate change.

National Research Council Canada: Ottawa, ON. 2021. 192 pp.

Heather Kreidler, Rapporteur; Board on Environmental Change and Society; Board on Agriculture and Natural Resources; Division of Behavioral and Social Sciences and Education; Division on Earth and Life Studies; National Academies of Sciences, Engineering, and Medicine

Over the past two decades, wildfires in western North America have significantly increased in frequency, magnitude, and severity. Scientists have documented three leading causes: a century of suppression and inadequate forest management that has led to overly dense, fuel-rich forests; climate change, which has turned woodlands and grasslands into hot, dry tinderboxes; and the spread of urbanization, which has increased the probability of man-made ignitions. Less well known are the environmental and social implications associated with the acceleration of these trends.

To explore these concerns and to identify possible policy responses, the National Academies of Sciences, Engineering, and Medicine's Board on Environmental Change and Society, in partnership with the Royal Society of Canada, convened a workshop in June 2024, "The Social and Ecological Consequences of Future Wildfire in the West". Over two days, two dozen wildfire experts and a hybrid audience of over 200 participants explored the history, current state, and anticipated future of wildfire science and policy across the western United States and Canada. This publication summarizes the presentations and discussions of the workshop.

National Academies of Sciences, Engineering, and Medicine. 2024. Social-Ecological Consequences of Future Wildfires and Smoke in the West: Proceedings of a Workshop. Washington, DC: The National Academies Press. https://doi.org/10.17226/27972.

Contributor(s): National Academies of Sciences, Engineering, and Medicine; Division on Earth and Life Studies; Board on Chemical Sciences and Technology; Committee on the Chemistry of Urban Wildfires

Wildfires in America are becoming larger, more frequent, and more destructive, driven by climate change and existing land management practices. Many of these fires occur at the wildland-urban interface (WUI), areas where development and wildland areas overlap and which are increasingly at risk of devastating fires as communities continue to expand into previously undeveloped areas. Unlike conventional wildfires, WUI fires are driven in part by the burning of homes, cars, and other human-made structures and in part by burning vegetation. The interaction of these two types of fires can lead to public health effects that are unique to WUI fires.

This report evaluates existing and needed chemistry information that decision-makers can use to mitigate WUI fires and their potential health impacts. It describes key fuels of concern in WUI fires, especially household components like siding, insulation, and plastic. It examines key pathways for exposure, including inhalation and ingestion, and identifies communities vulnerable to exposure. The report recommends a research agenda to inform response to and prevention of WUI fires, outlining needs in characterizing fuels and predicting emissions and toxicants.

National Academies of Sciences, Engineering, and Medicine. 2022. The Chemistry of Fires at the Wildland-Urban Interface. Washington, DC: The National Academies Press. https://doi.org/10.17226/26460. .2022. 215p.

U.S. Forest Service

Under this strategy, the Forest Service will work with partners to engineer a paradigm shift by focusing fuels and forest health treatments more strategically and at the scale of the problem, using the best available science as the guide. At the Forest Service, we now have the science and tools we need to size and place treatments in a way that will truly make a difference. We will focus on key “firesheds”—large forested landscapes and rangelands with a high likelihood that an ignition could expose homes, communities, and infrastructure to wildfire. Firesheds, typically about 250,000 acres in size, are mapped to match the scale of community exposure to wildfire.

Our new management paradigm builds on the National Cohesive Wildland Fire Management Strategy, Our new management paradigm builds on the National Cohesive Wildland Fire Management Strategy, including efforts to create fire-adapted communities and other collaborative strategies for cross-boundary treatments, including Cohesive Strategy projects and Shared Stewardship agreements. We will build on our long-standing work and relationships with U.S. Department of the Interior agencies. We will work collaboratively with States, Tribes, local communities, private landowners, and other stakeholders to adapt lessons learned into a coordinated and effective program of work.

U.S. Forest Service. 2022. 35p.