Southern Europe's intensifying heatwave continues to break weather-related records, bringing with it warnings of increased risks of wildfires, heart attacks and deaths due to the skyrocketing temperatures. 

The mercury remained high in Italy on Wednesday, with temperatures on the Italian island of Sicily hitting almost 47 degrees Celsius.

A man and woman aged 69 were found dead in their homes in the Sicilian capital Palermo on Tuesday, with local newspapers attributing their deaths to the heat.

In total, Italy was forced to put 23 cities on red alert due to the extreme weather, with peaks of 45 and 46C on parts of the Mediterranean island of Sardinia.

That's one day after the capital of Rome saw its highest ever reading, 41.8C, breaking the previous record of 40.7C set in June 2022.

The country's health ministry said teams of mobile health workers were visiting the elderly in the city in a bid to counter heat-related health risks.

"These people are afraid they won't make it, they are afraid they can't go out," said Claudio Consoli, a doctor and director of a health unit.

Wildfires in Greece

In Greece, wildfires burned for a third day west of the capital of Athens, with another blaze breaking out on the tourist island of Rhodes, forcing locals to decide whether or not to flee.

Accelerated by erratic winds, the fires on the Greek mainland have destroyed dozens of homes, prompted hundreds of people to flee and brought thick smoke to the area. 

Temperatures could climb to 43C on Thursday, forecasters said.

"I am not leaving. I started building this house when I was 27 years old by myself," said Dimitris Michaelous, a long-term resident in the fire-threatened town of Pournari, north of Athens. 

Local firefighters said Romania, Slovakia and Poland were set to send some 230 firefighters to help it tackle the blazes, as the government called on people to be extremely careful to not spark new fires.

Spain also warned of the risk of wildfires in most of the country, though residents were allowed to return to their homes in La Palma island where a blaze that raged for five days was stabilized in one sector, although it remained active elsewhere.

Free swimming pools

France said on Wednesday temperatures of up 40C would hit parts of the country's south, including on the Mediterranean holiday island Corsica.

In Marseille, the left-wing mayor Benoit Payan announced on Twitter that municipal swimming pools would be free "until the end of the heat wave," which is expected to last until at least Friday.

A high of 29.5C was recorded in the French Alpine ski resort of Alpe d'Huez, while 40.6C had been recorded for the first time in Verdun in the foothills of the Pyrenees. The figures are 8C to 11C above normal for the season.

The World Health Organization said the heatwave in the northern hemisphere was also putting an increasing strain on healthcare systems, hitting those least able to cope the hardest.

"Extreme heat takes the greatest toll on those least able to manage its consequences, such as older people, infants and children, and the poor and homeless," said WHO chief Tedros Adhanom Ghebreyesus.

The heatwave has become so severe that over in Germany, parliamentarians are discussing whether workplaces should introduce siestas for employees.

Extreme heat, floods in Asia

Meanwhile in Asia, the Chinese capital of Beijing - which this week was hosting U.S. climate envoy John Kerry for talks - broke a 23-year-old record with 27 consecutive days of temperatures above 35C.

On Sunday, a remote township in China's Turpan Depression registered a maximum air temperature of 52.2C, smashing China's national record of 50.3C set in 2015.

Other Asian nations have seen extreme rainfall and flooding, with dozens of people dying in two separate flooding and landslide incidents in South Korea over the weekend. 

In India, the Yamuna river reached the compound walls of the Taj Mahal in Agra for the first time in 45 years, also submerging several other historical monuments and gardens surrounding the 17th century, white-marble mausoleum. 

These unprecedented temperatures have brought a new urgency for nations around the globe to tackle the climate crisis. with the U.S.'s Kerry saying to Chinese Vice-President Han Zheng on Wednesday that climate change must be handled separately to broader diplomatic problems.

"It is a universal threat to everybody on the planet and requires the largest nations in the world, the largest economies in the world, the largest emitters in the world, to come together in order to do work not just for ourselves, but for all mankind," Kerry said.

We are ready to seek the greatest common ground on the basis of respecting each other's core concerns and make new contributions to addressing global challenges including climate change, Han said.