In recent years, Greece has experienced increasingly frequent and intense wildfires, the kind that a few decades ago would have been considered extreme outliers. The trend has raised a pressing question: how rare are mega-wildfires today?
Two Greek scientists from the University of Patras attempted to answer that question in a year-long study published last month. Using 28,658 fire events recorded by the Greek Forest Service and applying Extreme Value Theory, Professor of Mathematical Simulation of Environmental Systems Fragkiskos Koutelieris and Professor of Environmental Informatics, Remote Sensing and Geographic Information Systems Nikos Koutsias calculated the recurrence intervals of wildfires of specific sizes.
They emphasized that measuring wildfires solely by burned area is inadequate. A more complete approach includes “return period” calculations—estimating how often fires of a given magnitude can be expected.
From Rare to Frequent
Their findings show that in Greece:
- A wildfire burning around 3,600 hectares can be expected every two years.
- One burning 6,900 hectares occurs every five years.
- The 2021 Evia blaze, which destroyed 45,000 hectares, was equivalent to a 200-year event.
- The 2023 Dadia fire, which raged for 16 days and consumed 95,000 hectares, corresponds to an event expected once every 2,000 years.
“The understanding of expected frequencies is essential for authorities in planning resources, infrastructure, staff, and emergency services,” the professors told TA NEA. “Knowing whether a 5,000- or 10,000-hectare fire is likely once every 10 years or once every 50 years significantly affects preparedness and prevention strategies.”
Biomass Build-Up and Climate Change
Despite statistical expectations, Greece has seen multiple extreme fires within short intervals. According to Koutsias, climate change—with higher temperatures and prolonged heatwaves—has shifted the pattern, making once-rare events occur more often.
A major factor is the accumulation of biomass and fuel in forests. Until the 1970s, rural communities collected wood and grazed livestock, reducing combustible material. As people abandoned forests and agricultural work, fuel loads built up, contributing to massive fires.
“This is a Mediterranean-wide issue,” Koutsias said. “We need new ideas and solutions for biomass management. Ultimately, the key lies in lifestyle—remaining connected to rural areas and forests rather than abandoning them.”
When Flames Reach Greek Cities: Wildfires at the Urban Edge
The recent wildfires in Achaia, western Greece, burned 1,384 hectares in Kato Achaia and 761 hectares in Patras, according to the Region of Western Greece. The figures, derived from the EU Copernicus satellite system, show relatively modest fires compared with Greece’s typical large-scale events.
Professor of Environmental Informatics, Remote Sensing and Geographic Information Systems Nikos Koutsias of the University of Patras noted that wildfires burning around 36,000 stremmata occur every two years in Greece. “By comparison, the Achaia fires were quite small,” he explained.
Disproportionate Destruction
Despite their limited size, the Achaia wildfires caused outsized damage. They destroyed buildings, industrial facilities, vehicles, farmland, and forestland—threatening human lives as well, though without fatalities.
“These fires were particularly dangerous because they occurred in areas known as wildland-urban interfaces,” Koutsias said. “These are zones where urban and forest environments overlap, with people living effectively inside the forest. Fires of this type, though small, can have major consequences.”
A Growing Threat
Koutsias raised the concern that such wildfires could become more frequent in the future. Factors include the spread of wildland-urban interface zones, the accumulation of forest biomass due to lack of management, and the effects of climate change.
Managing Risk, Not Just Fire
The professor emphasized that these events highlight the need to rethink wildfire risk management. “Hazard is defined by the combination of three factors: the danger of the event itself, exposure to it, and vulnerability to its impacts. In Achaia, the risk was high not because of fire size but because of high exposure and high vulnerability,” he explained.
Effective wildfire management, he concluded, must address all three components—event hazard, exposure, and vulnerability—rather than focusing only on the fire itself.
Source: Ta Nea
