Concerns over global warming rise as extreme heatwaves effect the globe

Temperatures have reached new highs as heatwaves scorched parts of the Northern Hemisphere, triggering health warnings in the latest stark reminder of the effects of global warming.

From North America to Europe and Asia, people gulped water and sought shelter from the sweltering heat on Monday, with the mercury expected to reach new highs in several places in the next few days.

Europe, the globe's fastest-warming continent, was bracing for its hottest-ever temperature this week on Italy's islands of Sicily and Sardinia, where a high of 48 degrees Celsius is predicted, according to the European Space Agency.

With June already having been the world's hottest on record, according to the EU weather monitoring service, China reported a new high for mid-July in the northwest of the country.

At least 60 people in Japan were treated for heatstroke, local media reported, including 51 who were taken to hospital in Tokyo.

Historic highs forecast

In Europe, Italians were warned to prepare for "the most intense heatwave of the summer and also one of the most intense of all time," with the health ministry sounding a red alert for 16 cities, including Rome, Bologna and Florence.

Temperatures were due to hit 42C-43C in Rome on Tuesday, smashing the record of 40.5C set in August 2007.

Greece saw a respite on Monday as temperatures eased a bit, and the Acropolis in Athens resumed its regular opening hours after shutting for a few hours during the previous three days.

Little reprieve is forecast for Spain, where meteorologists warned that "abnormally high" temperatures on Monday, including up to 44C in the southern Andalusia region in what would be a new regional record.

Killer rains

Along with the heat, parts of Asia have also been battered by torrential rain.

South Korea's president vowed Monday to "completely overhaul" the country's approach to extreme weather, after at least 40 people were killed in recent flooding and landslides during monsoon rains, which are forecast to continue through Wednesday.

In northern India, relentless monsoon rains have reportedly killed at least 90 people, following burning heat.

Major flooding and landslides are common during India's monsoons, but experts say climate crisis is increasing their frequency and severity.

It can be difficult to attribute a particular weather event to climate change, but many scientists insist that global warming is behind the intensification of heatwaves.