Desmond and Linda Cornford left Brisbane five years ago because temperatures had become unbearable.

Key points: A University of Tasmania study has found climate is the biggest driver of migration to Tasmania

A University of Tasmania study has found climate is the biggest driver of migration to Tasmania Des and Linda Cornford fled Brisbane five years ago because it was "getting way too hot"

Des and Linda Cornford fled Brisbane five years ago because it was "getting way too hot" Australia is this week suffering through a heatwave, but Tasmania will mostly escape the sweltering weather

Mr Cornford said Brisbane was a country town when he moved there in 1977, but it had grown into a big city and he felt temperatures had soared.

"I think it has got warmer and I think the summers have got longer," he said.

"The winters, well there's really not a winter up there in our opinion, but it has changed a lot."

This year, Brisbane's July was its hottest on record.

South-east Queensland was also expected on Monday to break temperature records as the mainland swelters through a heatwave.

Mrs Cornford said the move was "just something that we had to do".

"It was just getting way too hot and the humidity was an absolute killer," she said.

"You couldn't do any gardening because it was just going to be too hot, you couldn't use your water because they were on restrictions. So Tasmania it was."

The couple moved to Port Sorell on Tasmania's north-west coast and couldn't be happier with their decision. In fact, they believe it's added years to their lives.

"Most of our time is spent in the garden which is wonderful, so that is extending our lives," Mrs Cornford said.

"We're exercising and we're enjoying it."

Climate most popular migration driver

The Cornfords are not alone.

A recent survey of people who had either moved to Tasmania or were considering doing so found climate and weather were the most commonly reported reasons for a tree change.

Environment was close behind.

Hot weather is short lived in Tasmania. ( Pixabay: Gerd Altmann )

The number of interstate arrivals has also been increasing.

In the year to March, 14,521 people moved from around Australia to settle in Tasmania, surpassing an average of 12,874 per year since 2003.

University of Tasmania demographer Lisa Denny from the Institute for the Study of Social Change said in the past, employment opportunities, connecting with family and lifestyle reasons were the main drivers behind people's decisions to relocate.

"We were actually surprised that climate and the environment was the number one reason for people coming and for people leaving where they came from," Dr Denny said.

"The risks of more natural hazards and natural events like floods and cyclones and bushfires, the costs associated with insurance are making people reconsider about where they live."

'Last climate refuge in Australia'

Professor of Sustainability at the University of Tasmania Barry Brook said heatwaves on mainland Australia would be hotter and more extreme in the future.

"I've heard a lot of people say Tasmania's the last climate refuge in Australia," he said.

"Although we will have hot days, we're not subject to the same extended hot periods.

"Places like the north-west coast are particularly mild, they have got Bass Strait around them and I've heard of a lot of people seeking to move there to escape those extreme conditions."

Simon McCulloch from the Bureau of Meteorology agreed.

"We generally don't get that really extreme heat," he said.

"So the temperatures on mainland Australia are pushing up into the 40s, we do get days pushing into the high 30s and the low 40s, but generally not a lot of them."

And Professor Brook said it would not be just humans seeking refuge in Tasmania.

"There are animal refugees and plants as well and one of the things I am interested in here is whether there's going to be mainland species not in Tasmania that can no longer cope with the conditions," he said.

"You see things that live in mountain ranges like in central Victoria in the Snowy Mountains, it might be their last refuge is Tasmania.

"So it's not just going to be people, it might well be species we have to think about moving permanently down here.

"It is a real possibility for some threatened ones, for example the mountain pygmy possum found only in snowy areas [in Victoria and New South Wales], if they're all gone from the mainland in 50 years the only place left [for them] will be Tasmania."