Mediterranean wildfires and its association with compound droughts, atmospheric heatwaves and adjacent marine heatwaves

Oral Presentation 

Climate change has become a major concern in the 21st century, leading to an increase in the 
frequency, duration, and intensity of extreme events. Heatwaves and droughts, amongst a panoply 
of other extreme events, have been rising in recent decades in the Mediterranean region, resulting 
in significant repercussions on ecosystems, human health, and several basic resources. This 
intensification has been reported both in atmospheric and marine ecosystems, as both 
environments can experience high-temperature events. These warmer conditions, both in land and 
in the ocean, often coupled with drier conditions, have particularly affected southern Europe and 
the Mediterranean region, which are highly vulnerable to climate change. 

Given the impact of these extreme events, occurring solely or in a compound manner, in 
exacerbating rural fires, we propose to analyse their co-occurring interplay in the Mediterranean 
Europe, examining the occurrence of atmospheric heatwaves and drought conditions in Southern 
Europe, and marine heatwaves in the East Atlantic and the Mediterranean Sea. Additionally, we 
investigate recorded rural fire incidence, exploring the prevalence of dry and hot conditions and 
their linkage to wildfires, on both an individual and compound approach, between 2001 and 2022. 

Our study concludes that years marked by stronger marine heatwave conditions tend to synchronize 
with heightened atmospheric heatwave and dry conditions over burned regions. Marine hot 
conditions dominate in months in which burned areas remain below the 80th percentile, while drier 
events prevail when burned areas surpass this threshold. Months marked by higher fire activity are 
predominantly associated to extreme climatic conditions (atmospheric heatwaves, marine 
heatwaves, drought conditions), showcasing a substantial occurrence of compound events. This 
study demonstrates the potential usefulness of considering both land-based atmospheric and 
marine conditions when exploring compound extremes, which might be crucial to ensure effective 
preparedness and mitigate the risks of climatic disasters, particularly wildfires.

This work was supported by the European Union’s Horizon 2020 research project FirEUrisk, with the 
Grant Agreement no. 101003890 and by national funds through FCT I.P./MCTES (Fundação para a 
Ciência e a Tecnologia) (PIDDAC) – c - IDL and by https://doi.org/10.54499/2022.09185.PTDC 
(DHEFEUS). AR acknowledges FCT for 
https://doi.org/10.54499/2022.01167.CEECIND/CP1722/CT0006 (Complex).