Climate change favors dangerous wildfire conditions in France and Spain

Prolonged drought, heat — and sparks are enough

Since spring, unusually persistent drought and recurring heat have affected wide parts of Western Europe. Vegetation and soils are desiccated; even small ignition sources such as sparks, discarded cigarettes or technical faults can start fires that quickly spread over kilometres. In southwestern France and in central and eastern Spain, these conditions have led to particularly intense blazes that are being fought with water bombers, extra crews and evacuations.

Attribution analysis: multiple risk factors are occurring together more often

The research initiative World Weather Attribution (WWA) examined the weather and soil conditions behind the current fires. The focus was on the combination of long-lasting drought, exceptional heat and dry vegetation. According to the analysis, human-caused climate change increases the probability that precisely these factors coincide — conditions under which local ignitions are more likely to grow into large, hard-to-control fires.

Why heat and drought amplify fires

Higher temperatures accelerate evaporation, causing plant material to dry out and become more flammable. Prolonged drought also draws water from deeper soil layers, making even resilient species more vulnerable. If strong winds are present, they feed the flames and carry embers over greater distances. The result is fire behaviour that can intensify rapidly and become difficult to predict.

Human ignition sources remain decisive

Many fires are started by human activities — for example by agricultural operations, carelessness, technical failures or arson. Under normal moisture conditions such incidents often remain local. Under the current heat and drought, however, they escalate far more frequently into large-scale forest and vegetation fires. Attribution research does not absolve ignition sources of responsibility; it shows that warmer, drier background conditions can enlarge the scale of damage.

Consequences for people, nature and infrastructure

Large fires force evacuations, harm health through smoke and threaten homes, roads and power grids. In the long term biodiversity and forest structure are lost, soils become more prone to erosion, and the risk of landslides or flooding after heavy rains increases. For affected regions this means high costs — from immediate damage to losses in agriculture and tourism.

Prevention and response: where improvements are needed

In widespread events, firefighting capacities are quickly stretched thin. What is needed are effective early-warning systems, tightly coordinated air and ground operations and logistics that can rapidly redeploy forces. Fire-resistant building practices, protective buffer zones around settlements and proactive evacuation plans also help limit damage.

Forest and landscape management as a lever

Controlled burning under safe conditions, mechanical removal of undergrowth, reforestation with heat- and drought-tolerant species and landscape mosaics of forest, pasture and open land reduce fuel loads and slow fire spread. Such measures require long-term planning, reliable funding and local acceptance.

Climate policy: without emissions reductions the risk will rise further

Adaptation can reduce harm but does not replace effective greenhouse gas reductions. As warming continues, heat and drought episodes become more frequent and can overlap, favouring extreme fire conditions. International and national climate policy therefore remains a central element of risk management.

What those affected should do now

– Follow official warnings and evacuation orders. – Keep windows and doors closed during heavy smoke, limit outdoor activities and follow health advisories. – Use local alert systems for information and coordinate neighbourhood assistance.

An event in the context of a larger trend

The fires in France and Spain are part of a series of extreme events that occur when heat, drought and wind act together. WWA places this clustering in the context of long-term climate change. Practical protection is possible — through better management, resilient infrastructure and tackling root causes. That requires coordinated action across regions and sectors.