Fire regimes are becoming increasingly volatile: implications for managing extreme fire events in the Mediterranean

Wildfire behaviour is becoming increasingly volatile, expressed through more frequent and pronounced episodes of anomalously intense fire activity. Conventional approaches to characterising wildfire intensity, particularly those based on satellite-derived fire radiative power, remain strongly tied to fire occurrence, making it difficult to distinguish between periods of widespread burning and genuinely anomalous or extreme fire behaviour.

Here, we demonstrate that departures from expected relationships between fire detections and energy release reveal increasingly frequent and pronounced episodes of anomalous fire behaviour. These anomalies are characterised not only by elevated total energy release, but by shifts in the upper tail of the fire energy distribution, indicating a growing prevalence of disproportionately intense fire activity. Importantly, this behaviour does not occur uniformly, but instead reflects distinct modes of fire activity, ranging from widespread high-energy burning to more localised, extreme events.

Across multiple regions and scales, these patterns point to a broader increase in wildfire volatility, defined by growing variability and instability in fire energy behaviour over time. This suggests that fire regimes are not only intensifying but becoming less predictable and more prone to rapid departures from expected conditions. Within this framework, Mediterranean ecosystems emerge as exhibiting episodic volatility, characterised by punctuated extreme fire activity, underscoring their sensitivity to climate-driven risk.

This emerging volatility has important implications for wildfire management under a changing climate. As fire behaviour becomes increasingly unstable, existing assumptions around fire growth, intensity, and spread may become less reliable, complicating forecasting, planning, and response. Recognising and accounting for increasing volatility will be critical for adapting wildfire management strategies to a future in which extreme and anomalous fire behaviour plays a more dominant role.