How asynchronous is fire burning in Iberia and the Central–Eastern Mediterranean? A dependence analysis of burned area, fire activity, and teleconnection forcing to inform shared European suppression fleets

European wildfire response systems are increasingly challenged by the simultaneous demand for aerial and ground suppression assets. If major fire-prone regions burn asynchronously, Europe could benefit from risk-diversified deployment of shared suppression fleets and more efficient cross-border mutual-aid strategies. We test the hypothesis that fire activity in (1) the Iberian Peninsula (Portugal and Spain) and (2) Central–Eastern Mediterranean (Italy and Greece) exhibits identifiable and temporally stable dependence patterns modulated by large-scale climate variability.
Annual burned-area time series covering 1980–2023 are compiled from the European Forest Fire Information System (EFFIS). These are complemented by satellite-derived indicators of fire activity from MODIS, namely Fire Radiative Power (FRP), enabling joint assessment of burned area extent and fire intensity. Climate-fires’ dependence is quantified through correlations of annual and seasonal anomalies and joint-extreme metrics focused on tail co-exceedance probability. The relationship between fire activity (burned area, FRP, FRE) and large-scale climate variability is assessed following established teleconnection-based frameworks, combining seasonal aggregation, lagged cross-correlation analysis, and composite analysis of extreme fire years. Teleconnection indices considered include the North Atlantic Oscillation (NAO), East Atlantic pattern (EA), Mediterranean Oscillation Index (MOI), Arctic Oscillation (AO), and ENSO. Analyses explicitly account for the non-stationary and scale-dependent nature of teleconnection–fire relationships, and are conditioned on regional temperature and precipitation anomalies to isolate circulation-driven effects.

The analysis aims to identify: (i) the frequency and persistence of synchrony versus compensatory (negative) dependence in burned area and fire activity between the two macro-regions, (ii) the teleconnections most strongly associated with synchronous extreme fire seasons, and (iii) multi-decadal periods offering potential for suppression-fleet diversification. Owing to its direct control on Mediterranean-scale pressure gradients and precipitation contrasts, MOI provides the primary explanatory signal for synchronous versus compensatory fire activity between the two macro-regions.

Results are interpreted within an operational risk-pooling framework, where weak or negative dependence supports climate-informed scheduling of shared European suppression fleets and enhanced cross-border mutual aid, while strong positive dependence indicates heightened likelihood of concurrent continental-scale resource strain.

 

This work is partially supported by FCT, I.P./MCTES through national funds (PIDDAC): LA/P/0068/2020 – https://doi.org/10.54499/LA/P/0068/2020, UID/50019/2025 – https://doi.org/10.54499/UID/PRR/50019/2025, UID/PRR2/50019/2025 and Dhefeus (https://doi.org/10.54499/2022.09185.PTDC). AR, JMCP and JMNS also thank the FCT by supporting UIDB/00239/2020 (https://doi.org/10.54499/UIDB/00239/2020), UIDP/00239/2020 (https://doi.org/10.54499/UIDP/00239/2020), and through project references UIDB/00239/2020 (https://doi.org/10.54499/UIDB/00239/2020) and UIDP/00239/2020 (https://doi.org/10.54499/UIDP/00239/2020) and European Space Agency Climate Change Initiative (ESA-CCI9 Tipping Elements SIRENE project (Contract No. 4000146954/24/I-LR).