ATHENS • Greece was battling four major wildfires on Sunday that have forced hundreds to evacuate, as soaring temperatures there and in Spain raised fears of more blazes.
The United States, meanwhile, sweltered in scorching heat set to exceed already record-setting temperatures, worsening an out-of-control wildfire in central California.
Scientists say human-induced climate change is amplifying extreme weather - including the heatwaves, droughts and floods seen in several parts of the planet in recent weeks - and add that these events will become more frequent and more intense.
The international community has agreed that climate change poses an existential threat to human systems and the natural world.
Earth's average temperature has warmed just over 1.1 deg C since the industrial era and the United Nations says it is currently on track to warm some 2.7 deg C this century.
Greece is in the grip of a heatwave that began on Saturday and is expected to last 10 days. Temperatures are set to rise to 42 deg C in some regions.
Fires raged in the north, east and south of the country, including on the tourist island of Lesbos, where around 200 people were ordered to leave the village of Vryssa on Sunday to escape the flames.
Elderly women left the village carrying a few possessions in plastic bags, as thick smoke engulfed the first houses.
In the north-eastern region of Evros, hundreds of firefighters battled a wildfire that has been ablaze for four days in Dadia National Park, known for its black vulture colony.
Evros Governor Dimitris Petrovits told Athens News Agency the authorities were doing all they could to protect locals and treat injured wildlife.
In Spain, a heatwave that has persisted for two weeks is expected to produce record-high temperatures of 45 deg C in the southern region of Cordoba.
This part of Andalucia registered Spain's highest-ever temperature - 47.7 deg C - only last year.
The national weather office said the relentless heatwave since July 9 and the lack of rain since the start of the year across the Iberian Peninsula meant there is an extreme risk of fires.
In all, fires in France, Spain and Portugal have already burned more land so far this year - some 517,881ha - than was destroyed by flames in all of last year.
Last Friday, the World Health Organisation said Europe's heatwave has led to "more than 1,700 needless deaths... in Spain and Portugal alone".
In the United States, where President Joe Biden warned last week that climate change represented a "clear and present danger", tinderbox conditions in California sparked a fire on Friday near the Yosemite National Park and its giant sequoia trees.
The fire - described as "explosive" by officials - spread from 250ha to 4,800ha within 24 hours, the California Department of Forestry and Fire Protection (Cal Fire) said.
Firefighters deployed air tankers, bulldozers and hand crews to battle the fast-moving wildfire that suddenly and unpredictably grew into one of the largest fires of the year, forcing thousands of evacuations.
Fuelled by extreme heat and tinder-dry forests and underbrush, the Oak Fire that began on Friday closed within 0.8km of the town of Mariposa Pines but was still more than 16km from Yosemite, famed for its giant, ancient sequoia trees.
By Sunday evening, the fire had consumed 6,314ha, more than half the size of Paris, and was zero per cent contained, according to Cal Fire. The fire was moving east up into the sierra, towards the town of Mariposa Pines and in the direction of Yosemite, Cal Fire operations section chief Justin Macomb told the public meeting.
"The fire quickly outflanked us. We couldn't even attack it with the resources that we had on hand," he said.
"In my career, I haven't seen fire behaviour like that."
Evidence of global warming could be seen elsewhere in the US, where 85 million people in more than a dozen states were under a weekend heat advisory.
AGENCE FRANCE-PRESSE, REUTERS