Human-caused climate change made the hot, dry and windy conditions that fuelled deadly wildfires in Spain and Portugal last month 40 times more likely, researchers said Thursday.

The Iberian Peninsula saw unusually high temperatures throughout August, with thermometers topping 40C in many areas.

The persistent heat fanned wildfires -- mainly in northern Portugal and western and northwestern Spain -- that killed four people in each country, forced the evacuation of thousands, and ravaged vast areas of land.

In Spain, more than 380,000 hectares have burned this year -- a record annual total and nearly five times the annual average, according to the European Forest Fire Information System.

Portugal has lost more than 280,000 hectares, almost three times the area usually burnt in a year.

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