Compounding Human and Bioclimatic Factors Driving the Global Fire Crisis

Over millennia, social and ecological systems have been shaped by fire and have in turn shaped fire regimes. However, recent decades have seen an escalating "fire crisis" characterized by an increasing incidence of large, intense wildfires, most notably in forests. Voices in the academic literature and media often attribute the fire crisis to a narrow range of mechanisms, for example, fuel management or climate change. This failure to acknowledge the complexity of causes leads to simplistic framings of risk, and ultimately, proposed solutions that are either not feasible or may lead to undesired outcomes. In this review we outline the human and bioclimatic factors that are driving this fire crisis. Factors reviewed include the impacts of colonial legacies, which disrupted Indigenous land stewardship and traditional burning practices over centuries; policies of fire suppression; population growth, urbanization and land management practices; biotic disturbances such as insect outbreaks and invasive plant species; and climate change, which is affecting both fire regimes and social-ecological resilience to fire. Many of these factors co-occur leading to complex interactions and, often, unexpected outcomes. Our review highlights that climate change is now having a compounding effect, building on a multitude of other factors to drive the fire crisis. Addressing this crisis requires first acknowledging its complexity and moving beyond simple framings of risk. We suggest solutions will vary across different places and through time, but may include supporting Indigenous land stewardship, adopting flexible fire responses, shifting societal expectations from aggressive fire suppression to "living with fire", and fostering resilient social and ecological communities.