"We don't want to risk it anymore because once in a lifetime's enough," Mr Hopkins said.

In the weeks after the fires swept through, he stood in the smouldering ruins of his home and wrote an open letter to Prime Minister Scott Morrison demanding he take climate change more seriously.

In the months since, he's only grown more angry.

Mr Hopkins - and others who lived through the fires - are hoping climate change is somehow addressed in the findings of the Royal Commission into National Natural Disaster Arrangements being released on Friday morning.

The royal commission was convened in the wake of the Black Summer fires, which killed 33 people and destroyed more than 3000 homes.

An estimated 3 billion animals were killed or displaced by the fires, which burned through between 24 and 40 million hectares of land.

The fires caused more than $2 billion in insured losses alone, while the economic impact on tourism, hospitality, agriculture and forestry has been estimated to be around $3.6 billion. There may have been a further $2 billion in health costs - in part from respiratory illnesses caused by the smoke.

The royal commission called 270 witnesses and examined more than 70,000 documents.

The report is expected to be 1000 pages long, with 80 recommendations.

Mr Hopkins is hoping it will drive home the need to cut greenhouse gas emissions urgently.

"To me ... there really needs to be a strong recognition at all levels of government, and in all agencies, that the driver behind the severity of these fires was climate change," Mr Hopkins said.

"It's like a house burning down - you don't move slowly or even moderately to put the fire out in a house fire, you move as quickly as you can."

David Darlington, a retired NSW National Parks and Wildlife Service regional manager and member of the Jindabyne Rural Fire Service, agrees.

"We are really hoping that the royal commission will say 'Hey, government, hey community, everyone needs to do a lot more to reduce our emissions'," Mr Darlington said.

Mr Darlington - a member of the Independent Bushfire Group - has been fighting fires for nearly 40 years and had never seen conditions like those in the Snowy Mountains over the summer.

"Normally, you see fires quieten down and not move much at all during the night, whereas this year we just saw fires even at 2 o'clock in the morning, firefighters were saying 'This is really difficult to contain, you know, it should be it should be much, much easier'," he said.

"There's no dispute, it's climate change in action."

READ MORE:

Tim Shepherd, a former National Parks and Wildlife Service regional manager from the NSW Far South Coast who is also part of the Independent Bushfire Group, said in the past he'd been wary about linking individual fires to climate change.

"I think now it's inescapable that climate change is a driver of catastrophic fires here and we've simply got to address the underlying issues in a fundamental way, so hopefully the commission will recognise it," Mr Shepherd said.

He also hoped the commission would recommend firefighters tackle fires earlier, by winching strike teams into remote areas as soon as an ignition is detected by satellites.

"Most, not all, of the major fires in NSW and elsewhere were lightning fires, and sometimes people got to them early but ... because of the conditions, couldn't get crews onto the ground, and they turned into various large fires," he said.

"Overall, if we could find ways in these catastrophic fire years to reduce the number of fires to get to, that's going to be a fundamental improvement in every way."

Mr Darlington said there needed to be dedicated helicopters and firefighters "that do nothing other than respond to remote fires".

"Last summer, we believe that had those additional resources been available and had we not had that that massive amount of smoke, a lot of fires that became mega fires probably would have been extinguished in the first few days," Mr Darlington said.

"We're going to see more of what we had last summer at some stage, and it won't be this summer, but we're going to have those climatic conditions reoccurring so we need to be ready for it."