This article has been peer reviewed and accepted for publication. It is in production and has not been edited, so may differ from the final published form.
What are the drivers of dangerous fires in Mediterranean France?
Wildfire containment is often very challenging for firefighters, especially for large and rapidly spreading fires where the risk of firefighter entrapment is high. However, the conditions leading to these ‘dangerous’ fires are poorly understood in Mediterranean Europe. Here, we analyze reports and interviews of firefighters over the last 40 years in four regions of south-eastern France and investigate the weather conditions that induce large fires, fast growing fires and fires that are conducive to entrapment. We adopt a quantile regression model to test the effect of weather conditions across different fire sizes and growth rates. The results show that strong winds drive the largest fires everywhere except in Corsica, the southernmost region, where high temperature is the main driver. Strong winds also drive entrapments whereas high temperatures induce rapidly spreading fires. This emphasizes that wind-driven fire is the dominant pattern of dangerous fires in France, but it also reveals that large ‘convective’ fires can also present considerable danger. Beyond that, the Fire Weather Index, already used in France to determine fire danger, appears to be a good predictor of large fires and fires conducive to entrapments. Identifying weather conditions that drive ‘dangerous’ wildfires will provide useful information for fire agencies to better prepare for adverse fire behaviors.
WF17087 Accepted 11 February 2018
© CSIRO 2018