Spain and Italy may still be among the most popular destinations for Europeans to take their vacations, but there are signs scorching weather in southern Europe has started to change travelers' calculations on where to go in the future.
According to the European Travel Commission, a Brussels-based association of European tourism organizations, the number of European tourists planning to travel to Mediterranean destinations in the summer and fall has dropped 10% compared with the same period last year.
Spain, Italy, France, Croatia and Greece were still the most popular destinations, but places like the Czech Republic, Bulgaria, Ireland, and Denmark had seen a "surge in popularity," the ETC said in a statement this month after conducting a survey of around 6,000 people.
"This can be attributed to travelers seeking out less crowded destinations, and milder temperatures," the association said.
This summer's extreme temperatures follow blistering heat last year. A growing preference for cooler vacation spots in the coming years would be bad news for countries on the Mediterranean Sea, especially those whose economies rely heavily on tourism.
Last year, the travel and tourism sector made up 18.5% of the Greek economy and more than 10% of Italy's economy, according to the World Travel & Tourism Council.
Pleasant weather remains the top consideration for Europeans when choosing where to vacation, according to the ETC survey, and 7.6% of respondents said the possibility of extreme weather during their European trip was their biggest concern.
A spokesperson at ForwardKeys, a travel data company, told CNN that "there has been a shift in preference towards cooler and more northern destinations" among UK travelers as a result of the heat waves in continental Europe this month.
"It appears that the increasing awareness of heat waves has prompted British travelers to seek out last-minute destinations with milder temperatures this summer," the spokesperson said.
Olivier Ponti, a senior researcher at ForwardKeys, said online searches in the United Kingdom for flights to southern Europe in the peak holiday months of July and August accounted for 58% of all flight searches at the start of July, down from 62% a month earlier. Meanwhile, online searches for northern European destinations increased by 3 percentage points to hit 10%.
Heat wave 'only just begun'
Italy, Spain and Greece have faced unrelenting heat for days, but the European Space Agency warned in a statement last week that the heat wave had "only just begun."
On Tuesday, the land surface temperature — that's how hot the ground feels to touch — reached 45 degrees Celsius (113 Fahrenheit) in Rome, and 50 degrees Celsius (122 Fahrenheit) in Nicosia, Cyprus, and the city of Catania in Sicily, Italy, according to the ESA.
"As climate change takes grip, heat waves such as this are likely to be more frequent and more severe, with far-reaching consequences," the ESA said in its statement.
Johan Lundgren, CEO of British airline easyJet, told reporters Thursday that the heat wave had not deterred tourists from taking their vacations in the usual places, but added that the airline had the flexibility to adjust its routes in the future if vacationers' preferences started to change.
Tourist hot spots are already having to make adjustments because of the sweltering heat.
Greek authorities said Thursday that the Acropolis and other archaeological sites would remain closed to visitors between midday and 5:30 p.m. local time till at least Sunday. Greece's meteorological service has warned that temperatures will rise further this week and are expected to reach 44 degrees Celsius (111 Fahrenheit) over the weekend in some parts of the country.
In Rome, several tourists have collapsed due to heat stroke this week, including a British tourist who fainted in front of the Colosseum Tuesday, according to Rome's civil protection chief Giuseppe Napolitano. The city has set up a command center to ensure crowds waiting to enter tourist sites have access to water, misting stations and shade when possible.
Southern Europe still popular with Brits
Despite rocketing temperatures, countries in southern Europe are still the go-to spots for many vacationers.
A spokesperson for UK travel agency Thomas Cook told CNN that the company hadn't seen "any difference whatsoever" in the numbers of its customers traveling to Mediterranean countries.
"Customers are happily heading out on their holidays right across the Med, and bookings recently have been as strong as they were at the start of the year," the spokesperson said.
Sean Tipton, a spokesperson for ABTA, an association of UK travel agents covering about 90% of the industry, told CNN that his members had seen "zero evidence of cancellations," and that people were keen to take their holidays, which they had booked far in advance.
Spain, Greece and Turkey are still "by far the most popular [destinations]," he said, which hasn't "changed at all."
— Barbie Latza Nadeau and Chris Liakos contributed reporting.