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Abstract BackgroundThe global human footprint has fundamentally altered wildfire regimes, creating serious consequences for human health, biodiversity, and climate. However, it remains difficult to project how long-term interactions among land use, management, and climate change will affect fire behavior, representing a key knowledge gap for sustainable management. We used expert assessment to combine opinions about past and future fire regimes from 99 wildfire researchers. We asked for quantitative and qualitative assessments of the frequency, type, and implications of fire regime change from the beginning of the Holocene through the year 2300. ResultsRespondents indicated some direct human influence on wildfire since at least ~ 12,000 years BP, though natural climate variability remained the dominant driver of fire regime change until around 5,000 years BP, for most study regions. Responses suggested a ten-fold increase in the frequency of fire regime change during the last 250 years compared with the rest of the Holocene, corresponding first with the intensification and extensification of land use and later with anthropogenic climate change. Looking to the future, fire regimes were predicted to intensify, with increases in frequency, severity, and size in all biomes except grassland ecosystems. Fire regimes showed different climate sensitivities across biomes, but the likelihood of fire regime change increased with higher warming scenarios for all biomes. Biodiversity, carbon storage, and other ecosystem services were predicted to decrease for most biomes under higher emission scenarios. We present recommendations for adaptation and mitigation under emerging fire regimes, while recognizing that management options are constrained under higher emission scenarios. ConclusionThe influence of humans on wildfire regimes has increased over the last two centuries. The perspective gained from past fires should be considered in land and fire management strategies, but novel fire behavior is likely given the unprecedented human disruption of plant communities, climate, and other factors. Future fire regimes are likely to degrade key ecosystem services, unless climate change is aggressively mitigated. Expert assessment complements empirical data and modeling, providing a broader perspective of fire science to inform decision making and future research priorities.
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This content will become publicly available on April 17, 2026
Novel wildfire regimes under climate change and human activity: patterns, driving mechanisms and ecological impacts
Fire regime refers to the statistical characteristics of fire events within specific spatio-temporal contexts, shaped by interactions among climatic conditions, vegetation types and natural or anthropogenic ignitions. Under the dual pressures of intensified global climate changes and human activities, fire regimes worldwide are undergoing unprecedented transformations, marked by increasing frequency of large and intense wildfires in some regions, yet declining fire activity in others. These fire regime changes (FRC) may drive responses in ecosystem structure and function across spatio-temporal scales, posing significant challenges to socio-economic adaptation and mitigation capacities. To date, research on the patterns and mechanisms of global FRC has rapidly expanded, with investigations into driving factors revealing complex interactions. This review synthesizes research advancements in FRC by analysing 17 articles from this special issue and 249 additional publications retrieved from the Web of Science. We systematically outline the key characteristics of FRC, geographical hotspots of fire regime transformation, critical fire-prone vegetation types, primary climatic and anthropogenic drivers and ecosystem adaptations and feedbacks. Finally, we highlight research frontiers and identify key approaches to advance this field and emphasize an interdisciplinary perspective in understanding and adapting to FRC. This article is part of the theme issue ‘Novel fire regimes under climate changes and human influences: impacts, ecosystem responses and feedbacks’.
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- PAR ID:
- 10651080
- Publisher / Repository:
- Royal Society
- Date Published:
- Journal Name:
- Philosophical Transactions of the Royal Society B: Biological Sciences
- Volume:
- 380
- Issue:
- 1924
- ISSN:
- 0962-8436
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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