Southern Europe sweltered under a fierce heatwave on Thursday, with a warning that temperatures could hit record highs for the continent next week, raising fears about the impact on human health, crops and animals.
Weather alerts were in place across Spain's Canary Islands, Italy, Cyprus and Greece, with the Greek authorities expecting temperatures to reach as high as 43 Celsius or 44 Celsius on Friday or Saturday.
Authorities put an ambulance on standby near the archaeological site of the Acropolis in Athens, ready to provide first aid to tourists wilting in the heatwave, which Italy's Meteorological Society has named "Cerberus".
The European Space Agency (ESA), whose satellites monitor land and sea temperatures, said July could be a torrid month.
"Italy, Spain, France, Germany and Poland are all facing a major heatwave with temperatures expected to climb to 48 Celsius on the islands of Sicily and Sardinia – potentially the hottest temperatures ever recorded in Europe," it said.
The impact of extreme summer heat has been brought into focus by research this week that said as many as 61,000 people may have died in Europe's sweltering heatwaves last summer.
Governments and employers are under pressure to do more to protect workers exposed to the burning sun in the latest heatwave, named after the three-headed dog of the underworld in Greek mythology.
There are concerns about the impact on those working outdoors in Italy after a 44-year-old man who was painting road markings in the northern town of Lodi collapsed and died this week.
"Heat is a silent killer. So this is the main concern that people's lives are at risk," said climate scientist Hannah Cloke, a professor at England's Reading University.
"Certainly, we should immediately stop pumping greenhouse gases into the atmosphere," Cloke added, warning that some changes to the climate were already locked in.