Like many Parisians, Mathilde Martin used to escape to the south of France at the height of the summer. But three years ago, a blistering heatwave made her rethink trips to the region where she grew up and her parents live.

“Rising temperatures have been a gamechanger,” the 51-year-old teacher said, after an experience a couple of summers ago: “We were near Perpignan during the summer and suffered scorching heat. That week was anything but enjoyable. It felt difficult to breathe at times. My parents, who live in Nice, have repeatedly told me at times in a worried tone that it hasn’t rained for months.”

Since then, she opts to take the train somewhere cooler during the summer’s peak – this year she will hike along the south coast of England – and instead head south in the spring or autumn. “It’s not as hot, and the sea is still warm sometimes. Last year, my parents were having lunch in the garden until December. The area is suffering from climate change and drought.”

As scorching heatwaves intensify and the frequency of wildfires surges, Martin is one of many European travellers who has changed how they plan their holidays. Three in four (76%) European travellers are adapting their behaviour to the climate crisis, according to a new survey by the European Travel Commission (ETC) shared exclusively with the Guardian.

In a sign that extreme weather is weighing on the minds of travellers and industry professionals, the ETC this year began polling respondents on how the climate emergency affects their travel arrangements.

A third (33.7%) of Europeans said they avoided destinations where extreme weather events were likely, the ETC poll found, and 17.3% said they did this by avoiding places with severe temperatures. Just more than 16% sought out holiday destinations with more stable weather conditions. Almost one in 10 (8.5%) said they were changing the months they travel, while one in 10 travellers said they worried about extreme weather.

But alongside these hints of the beginning of a shift, the ETC’s report, which polled people from Germany, the UK, France, the Netherlands, Italy, Belgium, Switzerland, Spain, Poland and Austria, still found that July and August are the most popular months for travel between May and October, while warmer destinations – Italy, Spain, France and Greece – all remained top destinations.

A preference for holidaying during the “shoulder season” – the months either side of the traditional high season of July and August – appeared more marked among UK travellers. The latest available data from ABTA – the Travel Association, the trade association for UK tour operators and travel agents, suggested October, May and June are the now most popular months for overseas breaks.

Some travel companies are also reporting increased interest in cooler destinations. Laura Greenman, the managing director of Magnetic North Travel, a tour operator specialising in holidays to cooler climes, said that inquiries for family holidays by UK and Irish customers doubled for summer 2024 compared with last year. There had also been a rise among couples. “Nearly all of these clients state the reason for selecting Scandinavia as being cooler than other European countries in summer,” Greenman said.

Also reflecting this trend, small-group tour operator Intrepid Travel reported recording a 40% rise in bookings for Scandinavian destinations compared with last year among UK customers, Hazel McGuire, the company’s UK and Ireland general manager, said. Meanwhile, dangerously high temperatures mean that, as of last year, the company no longer runs hiking trips in Spain, Turkey and Portugal during July and August.

Stephen Brown, 38, was among those swapping the sparkling seas of the Mediterranean for rugged northern landscapes. In recent years, Brown, a software engineer in London, has returned to the Scottish Highlands – a decision boosted by the fact that the capital, along with southern Europe, has also been experiencing heatwaves in recent years.

“I get enough heat here – we live in a top floor flat that gets super hot. I feel scarred from sitting in my underwear on that 40C day two summers ago. I could feel the heat when I breathed. My escape is being able to go north,” said Brown, adding that the ability to travel without flying has also been a key factor. “As well as being compatible with climate concerns, this has helped me scratch my itch for being active in the outdoors.”

Alongside hiking, kayaking and cycling, Brown often visits areas home to local nature restoration initiatives. “It’s wonderful to see work being done to rewild overgrazed and barren landscapes and it makes me positive about the future.”

This summer, as well as heading to the area around Loch Lomond, Brown will be travelling to Norway for the first time for a week of “hiking and kayaking through the fjords”.

Eduardo Santander, CEO of the European Travel Commission, said stable weather was essential for travel and tourism. “We recently began surveying European travellers on how they adjust their plans in response to changing weather patterns. Our findings show that travellers are increasingly aware of extreme weather events and their potential impact on their vacations.

However, these worries tend to be short-lived. Travellers may worry after summer but often overlook these issues when booking their next summer holiday.

“Looking ahead, we anticipate that shifting weather patterns could impact seasonal tourism flows in Europe. Cooler destinations may gain popularity in summer, and travellers might increasingly choose southern Europe for visits in spring and autumn, avoiding peak months.”

While Luka Goyarrola’s home, Mallorca, is widely considered a summer paradise, he will head to Sweden for a month in mid-August. Heatwaves have intensified on the Balearic island, but it is not just that which has made Goyarrola and his girlfriend decide to spend time elsewhere. Local people are paying the price for over-tourism, the 36-year-old artist and teacher believes: “I feel happy and fortunate to call it home, [but] it’s increasingly becoming an elite destination. The island has become a theme park.”

The couple plan to stay in Stockholm for a month, after Goyarrola’s girlfriend arranged a house swap with a colleague in Sweden. The destination was less important than the chance to have a break: “Any other place would have worked that was a bit cooler and less busy.”

“Maybe 10 years ago I wouldn’t have dreamed of it – summer was great here. It used to be easy to weather the heat – you just went in the sea. But now I don’t even think about going to the beach,” Goyarrola said.