Wildfires in Portugal: An overview

Wild Fires in Portugal: An overview
Fire in Ponte da Barca, Braga. Photo: Noticiasaominuto

Pray for Portugal has been trending all over social media helping the small southern European country gain global attention. Sadly, wildfires in this part of the world are not new. Fires became a characteristic in the Mediterranean area in a climate one could call a fire-prone environment. There’s no denying that wildfires are crucial for biodiversity, but why did they become more frequent and harder to extinguish in Portugal? Are they natural or human-caused? What are the long-term risks? And what are the solutions?

A brief history of wildfires in Portugal

In Portugal, humanity's impact on forests through the use of fire, dates back to the Bronze Age. But, there isn’t a lot of historic documents talking about large wildfires before the 20th century. Silva and Batalha report that the region of Pinhal de Leiria (Leiria National Forest) was affected by several fires between 1818 and 1824, the latter reaching 5,000ha. Also in his work "The Pinhal do Rei", Pinto reports that a forest fire in 1824 consumed about 5,000ha in Pinhal de Leiria. "Four days in Serra da Estrela", a 1884 book by Navarro states that there was a fire of great proportions in Matta do Bussaco in 1882 or 1883.

Wild Fires in Portugal: An overview
Reconstruction of Vale do Rio, 1961. Photo: Municipal Library of Figueiró dos Vinhos

In the 20th century, there have been reported incidents of wildfire, but non reaching 10,000 ha. Some of the recorded fires are Vale do Rio (Leiria, Figueiró dos Vinhos) in 1961, Viana do Castelo (1962), Boticas (1964) and Sintra (1996). Up until the 60s, wildfires weren’t a big issue in Portugal, but after that, the situation worsen.

The increase in damage done by wildfires might have been caused by changes in the traditional land use and lifestyle of the population. Subsequently, the changes led to the increase of large abandoned areas of previous agricultural lands. This helped vegetation recovery and forest expansion. But on the other hand, it led to flammable materials accumulation. Many new rural areas have become prone to high-intensity fires due to biomass levels accumulated over the years. abandoned areas were ready to feed catastrophic fires during the summer. Thus, wildfires never reached 10,000 ha until the 1986 fire that hit Vila de Rei and in the 1987 fire affecting, Arganil, Oliveira do Hospital and Pampilhosa da Serra. After these incidents, Portugal has officially entered a new phase.
Wild Fires in Portugal: An overview
Figure 1: Area burned annually in continental Portugal a) 1991- 2000 b) 2001- 2010. (Ferreira-Leite, 2013)

Dangers on health and environment 

Forest fires play an important role in the carbon cycle because they aid the decomposition of organic material. They also promote spatial heterogeneity - important for biodiversity. But fires also release different compounds into the atmosphere which can have negative effects on the environment and therefore considered pollutants. Fires cause significant environmental and socio-economic damage in the affected forest areas.

The most common effects are on health, climate, ecosystem and the chemistry of the atmosphere. Less studied and considered effects are the decrease in atmospheric visibility, contamination of soils and soil loss of nutrients and aquifers.

Furthermore, atmospheric emissions of pollutants from fires have substantial effects on human and animal health. These effects are a result of inhaling toxic gases. These intoxications are mainly associated with carbon monoxide inhalation which caused hemoglobin inactivation and may sometimes result in fainting or death. Breathing carbon monoxide can also decreases people's capacities to defend themselves and move away to safer places. In summer 2003, Portugal, 21 people died and more than 1,000 receive medical attention due to smoke poisoning. Most vulnerable of the population when the fire expands are elderly, children and the sick.

"Why?" The question on everyone's minds

Research shows a reduction in the number of large forest fires over the years. On the other hand, there is an increase in the area burned by the large fires. Knowledge of the causes of fires is crucial in defining the best strategies in reducing the damage done by wildfires.

Up to 2005, only 5% of national wildfire occurrences were investigated by Guarda Florestal (Forest Guard). In 2006, the Forest Guard were integrated into GNR (Republican National Guard) which increased investigations up to 12%. In 2013, the percentage of occurrences investigated reached 76% in continental Portugal. However, the increase in number of investigations was not helpful since the cause of 28% of the cases in 2013 couldn’t be determined.
Wild Fires in Portugal: An overview
Figure 2: Average number of fire occurrences with proven cause 2003-2013. (ICNF, 2013)

Furthermore, the numbers do not add up. Between 2003 and 2013, the District of Porto had the highest number of wildfires occurrences (5,522) which equates to 24% of wildfires on the national scale. But the investigations were the lowest on the national level (16%).

Possible Solutions

Professor Paulo Fernandes from the Forest Department, Center for Studies in Ecosystem Management University of Trás-os-Montes and Alto Douro says, complete elimination of wildfire is not possible and in some cases, not desirable. The goal is to reduce the expansion and severity of wildfires by implementing balanced fire management policies. In other words, the goal is to control fire by controlling its fuel, making it easier to combat.

But due to the unpredictableness of fires, financing these prevention projects can be complex. However, investing in prevention is much more important than investing in repairing the damage caused by wildfires. Fernandes say current knowledge is strong enough to guide the manipulation of forest structure in the sense of reducing its vulnerability to fire And in the near future, there is a marked preventive forestry and flammable material management. Also, computer applications can help examine the consequences, behavior and severity of a potential fire.


Thanks to the extensive research done on wildfires, we can now focus on fire prevention rather than damage repair. Although investigating a fire is important, getting occupied with the cause is unproductive. There’s a clear problem in resource allocations in Portugal and the data proves it.

Financially speaking, it’s difficult for Portugal to implement prevention programs. However, preventing deaths and uncontrollable wildfires is more important than budget deficit goals. The government representatives should start a volunteer campaign from people all over the world to help clean up the forest before the fire starts eating everything in sight during the summer. There’s no denying that humans are the main cause of the worsening of wildfires. Therefore, it’s human's responsibility to try and repair the damage and prevent it from happening again. With all the technologies and resources available we should be better at managing and preventing fire expansion, not worse.


Ferreira-Leite, Flora, António Bento-Gonçalves, Luciano Lourenço, Xavier Úbeda and António Vieira. "Grandes Incêndios Florestais em Portugal Continental como Resultado das Perturbações nos Regimes de Fogo no Mundo Mediterrâneo." Silva Lusitana (2013): 127-142. 

ICNF. "Análise Das Causas Dos Incêndios Florestais: 2003-2013. (2015). http://www.icnf.pt/portal/florestas/dfci/relat/relat-causa-incendios-2003-2013.

Santos Pereira, João, José M. Cardoso Pereira, Francisco Castro Rego, João M. Neves Silva and Tiago Pereira da Silva. “Incêndios Florestais em Portugal Caracterização, Impactes e Prevenção.” Instituto Superior de Agronomia (2006): 7-515.